Category: WW2 German SPG Prototypes

Projekt NM

German Reich (1943)
Self-Propelled Gun Battery – None Built

This vehicle, known only from a single blueprint, is possibly one of the strangest tracked war machines ever designed. German blueprint HSK 3485, dated 15 June 1943, named Project “NM”, shows a monstrous and ungainly vehicle consisting of three Tiger tanks joined together by I-beam girders. Built atop the I-beam frame sits a warehouse-like structure, concealing three 150 mm cannon-armed turrets. The reasoning behind this design, its purpose, and even which branch of the Wehrmacht it was for, remains a total mystery.

Details: Not Many

The only known original document pertaining to this vehicle is a single blueprint held in RH 8/2590K at Bundesarchiv Freiburg, filed under “Wa.Prüf.6 Technical Drawings.” Wa. Prüf. 6 was the central office for the design and development of tanks and armored vehicles under the Waffenamt, the German agency in charge of weapons. The blueprint was drawn in a 1:40 scale and shows a side, top, and front view of the vehicle, as well as details of the doors. The blueprint is only a rough draft, meaning that many components that would be present to make a functional vehicle are not drawn in. Additionally, close inspection reveals faint lines where the design had been erased and changed.

Projekt “NM”, Blueprint HSK 3485, 15 June 1943 – RH 8/2590K, Bundesarchiv Freiburg

Forming the base of the vehicle are three modified Tiger hulls, each with a U-shaped cutout in the area of the turret ring, which is implied to hold a gimbaling system that supports the vehicle’s frame. The tanks are arranged in a tricycle configuration, with a single tank at the front of the vehicle, and two in the rear. Lengthwise, the distance between the pivot point of the forward tank hull and the pivot points of the rear tank hulls is 14 meters (45’ 11’’). A faint outline of the rear tank hull in the blueprint side view shows that the rear hulls would be able to pitch up to 15.5° up or down relative to the frame. A similar range of motion is likely for the forward tank hull, but this is not shown in the blueprint. It has been theorized that these Tiger hulls would be made out of mild steel of thinner gauge than the normal tank, as the NM would not likely be intended to take enemy fire, and this alteration would save weight. Alternatively, the NM may have incorporated older non-combat-worthy Tigers that were gutted and repurposed.

Forming the backbone of the vehicle’s frame are four longitudinal I-beams, connected by ten transverse I-beams. All of the transverse I-beams sit atop of the longitudinal I-beams, apart from the one at the very rear, which is attached underneath. There are three main transverse I-beams that run the full width of the vehicle and are merely structural to the frame. Three shorter beams, spanning one-third the vehicle’s width each, sit one under each turret, on either side of the main structural member. At the very front of the vehicle and toward the rear, are two sets of two slightly thinner I-beams, which run the width of the frame and attach to the pivoting mechanisms on the tank chassis. The front corners of the otherwise square frame are rounded off into triangular sections. Faint lines on the blueprint evidence that, in an earlier iteration, these triangular sections extended all the way beyond the front of the forward tank hull, and were joined by another underslung transverse I-beam, similar to the one at the rear. This was likely determined to be unnecessary, and the frame was cut back to just meet the center of the forward tank hull. The vehicle would measure about 21.6 meters (70’ 10’’) in total length and 16 meters (52’ 6’’) in total width. Extrapolating from other values on the blueprint, the height of the vehicle can be calculated to be 5.15 meters (16’ 11’’). The bottom of the longitudinal I-beams would be 1,180 mm (3’ 10’’) off the ground. The height of each of the I-beams was 500 mm (1’ 8’’), meaning the frame accounted for a full meter (3’ 3’’) of height by itself. This would mean the top of the frame would sit 2,180 mm (7’ 2’’) off the ground, however, the blueprint shows this to be 2,280 mm (7’ 6’’). Most of the numbers given on the blueprint are approximate values, leading to such inconsistencies.

Mounted on top of the vehicle’s frame were three turrets, each housing a single 150 mm cannon. The central turret was staggered slightly behind the two outer turrets, which were placed just ahead of the rear tank hulls. All three of the turrets faced over the rear of the vehicle. Two 300 mm (1’) tall I-beams are placed longitudinally under each turret. The ends of these beams are shown to be cut down into points; the reason for this is unknown. The turrets rest directly on these I-beams, without any turret rings having been drawn. Should the design have advanced any further, this obviously would have needed to be changed. The turrets themselves measure 3.4 meters (11’ 2’’) long and 2.8 meters (9’ 2’’) wide, tapering toward the front. Each turret has -8° of gun depression, and +10° of gun elevation. The centers of the cannon barrels sit 3.4 meters (1’’ 2’’) off the ground. The distance between the centerline of the central turret and the centerline of either of the outboard turrets is 5.4 meters (17’ 9’’); the distance between the centerlines of the outboard turrets is 10.8 meters (35’ 5’’). Just in front of the outboard turrets, slung between the I-beams of the vehicle’s frame, are a pair of storerooms. It is likely these would have carried everything needed for the vehicle, including ammunition, and provisions for the tank and gun crews. They measure 4.5 meters (14’ 9’’) long, 4.5 meters wide, and 1.2 meters (3’ 11’’) tall.

Concealing the turrets is a simple warehouse-like building measuring 8.4 meters (27’ 7’’) long by 15.35 meters (50’ 4’’) wide, and approximately 3.97 meters (13’) tall. The width of the warehouse is the width of the frame discounting the two outermost longitudinal I-beams. This is a difference of 650 mm (2’ 2’’), which implies the width of the I-beams to be 325 mm (1’ 1’’). There is 1.9 meters (6’ 3’’) of space between the rear of the central turret and the front wall of the warehouse, and 0.8 meters (2’ 7’’) of space between the sides of the outboard turrets and the sides of the warehouse. The warehouse is supported by ten vertical supports around its perimeter, and at least five transverse supports in the roof. The barrels of the cannons protrude past the rear wall of the warehouse and are accommodated by a set of doors each. Curiously, in the forward view of the blueprint, these doors are shown to open horizontally, while in the top right corner of the blueprint an alternative arrangement is shown where they open vertically. The set of doors for the center turret is slightly larger than the doors for the other two turrets, as the center turret is farther away, and thus needs more room around the door to afford its barrel the same degree of traverse and elevation.

User: Navy Maybe?

There are two schools of thought as to what the purpose of this vehicle was. The first is that it was destined for use on the plains of the Eastern Front, but there are several problems with this theory. Firstly, a large warehouse slowly creeping across a field is not very inconspicuous. Second, the NM would be unable to cross rivers, neither by fording, due to its sheer size and ungainliness, nor by bridges, due to its width. On the Eastern Front, it would be relegated to very situational defensive positions, where it could be camouflaged in a position anticipating an enemy attack. The fact that the cannons face over the rear of the vehicle indicates that the ability to quickly retreat (as quickly as such a contraption could move) was a consideration. In a situation advantageous to the NM on the Eastern Front, such as overlooking a large open plain, where its 150 mm cannons would be able to far outrange the enemy, there would be nowhere for the vehicle to run once its disguise is lifted. On top of this, the nearly 22-meter long moving warehouse would be extremely vulnerable to Soviet artillery and ground attack aircraft. There is also the fact that the NM offers zero advantages in this situation over three separate Self-Propelled Guns (SPGs) armed with three separate 128 mm cannons, such as the Jagdtiger, then in development.

The second possible use for the vehicle is also the much more likely one: that of a mobile coastal defense installation. A warehouse perched on a cliff is not likely to draw any undue attention from enemy ships, and careful positioning would allow the NM to extricate itself before the enemy returned fire. Were the vehicle intended for use on the Eastern Front, it would certainly be a project of the Heer (Army), while both the Heer and the Kriegsmarine (Navy) operated coastal defense installations in the west. The name and armament of the vehicle, in addition to its suspected use as a coastal defense installation, point to the NM being a Kriegsmarine project. The name of the project, “NM”, is unlike any project name used by the Heer, and is closer to the naming scheme used by the Kriegsmarine.

The size of the turrets and cannons in the Projekt NM blueprint, comparable to the length of the Tiger tank which they are carried by, puts the cannons as being in the range of large 150 mm’s. German 15 cm cannons are only nominally 150 mm, in actuality, they have a bore diameter of 149.1 mm. Both the Heer and the Kriegsmarine operated numerous types of 15 cm cannons. Through careful consideration of their sizes and service dates, the possible armament of the NM can be narrowed down to four cannons. From the Heer, the 15 cm K. 18 and 17 cm K. 18, and from the Kriegsmarine, the 15 cm TbtsK C/36 and 15 cm SK C/28. All four of these cannon types were employed in some form as coastal defense guns.

The Projekt NM blueprint shows the cannon barrels extending 5120 mm (16’ 10’’) past the front plate of their turrets, and the turrets measuring 3400 mm (11’ 2’’) in length by themselves. This is a total combined length of 8520 mm (27’ 11’’). The 15 cm Torpedobootskanone C/36 is the smallest of the four cannon candidates, at just over 7 meters (23’) in overall length; this is the only one of the four cannons that would fit entirely inside the turret, and allow the turret to be wholly enclosed. The size of the other three cannon types, 8200 mm (26’ 11’’) for the 15 cm Kanone 18, 8291 mm (27’ 2’’) for the 15 cm Schiffskanone C/28, and 8529 mm (28’) for the 17 cm Kanone 18, would necessitate the turrets to be open at the rear, which is common for naval turrets but is contradicted by the presence of an enormous gun mantlet, which lightly armored naval turrets lack. Unfortunately, the Projekt NM blueprint does not show the rear of the turrets, and the details of their construction cannot be ascertained.

The secondary turrets of the Deutschland-class heavy cruisers, in this case, the half-sunken Admiral Graf Spee, mounted single 15 cm SK C/28 cannons. This cannon is likely what the NM would have been armed with if it was indeed a Kriegsmarine project. Source: http://www.navweaps.com/Weapons/WNGER_59-55_skc28.php

Operationally, the NM would likely be deployed to a Seeverteidigung (Sea Defense Zone) where an attack was expected, or where the defense force needed strengthening. The vehicle would be reversed into position overlooking a swath of sea, and camouflaged to best appear as a non-threatening structure. When an enemy vessel came within range, the doors of the warehouse would be swung open, allowing the vehicle’s three turrets to take aim and fire. The NM would probably have time enough to fire a few salvos before the enemy vessel realized it was being engaged by a warehouse, and not by surface vessels or gun emplacements. When the vehicle started to come under return fire, the NM could simply drive forward to move out of danger.

Unsurprisingly, attaching three Tiger chassis together with steel girders and putting three ship’s cannons and a warehouse on top was not seen as a very practical idea, and the NM did not advance any further.

Conservative illustration of the Projekt NM, not adding any details not seen on the blueprint. Had the NM been built, it would have required additional components to be a functional vehicle.

Illustration of the Projekt NM with the warehouse walls removed.

Projekt NM Specifications
Length:	21.6 meters (70’ 10’’)
Width:	16 meters (52’ 6’’)
Height:	5.15 meters (16’ 11’’)
Armament:	3x 149.1 mm cannons, likely 15 cm SK C/28

Sources

Projekt “NM”, Blueprint HSK 3485, 15 June 1943 – RH 8/2590K, Bundesarchiv Freiburg
Der Panzerkampfwagen Tiger und Seine Abarten – Walter J. Spielberger, 1997
Enzyklopadie Deutscher Waffen 1939-1945 – Terry Gander, Peter Chamberlain

WW2 German SPG Prototypes

Grille 17/21 Self-Propelled Guns

Post author By Craig Moore
Post date November 4, 2017
22 Comments on Grille 17/21 Self-Propelled Guns

German Reich (1942)
Self-Propelled Gun – 1 Built

The Tiger gun carrier

On the 6th of May 1942, the German weapons manufacturer Krupp submitted a proposal for the construction of a new armored self-propelled gun carriage that used components from the Panzerkampfwagen VI Tiger. While it was based on the Tiger tank chassis design, it was radically altered. It was meant to be able to carry two different guns.

The Grille 17/21 chassis is on the right of the photo next to a King Tiger with the early turret and a Panther tank on the far left. Behind the three vehicles is a Jagdtiger SPG. They were all captured at the Henschel Panzerversuchsstation, Haustenbeck Ordinance proving ground. (The Tank Museum, Bovington)
The vehicle was named, in typical German fashion, the ‘Geschützwagen Tiger für 17 cm Kanone 72 (Sf.)’ or the ‘Geschützwagen Tiger für 21 cm Mörser 18/1 (Sf.)’, depending on the gun mounted.
The German word Geschützwagen literally translates to ‘gun vehicle’. This is not an accurate description of the concept behind this artillery self-propelled gun. A gun carriage would be a better description. Unlike other German self-propelled guns, this vehicle was designed to mount different weapons. It was a modular concept. The vehicle was given the shorter names of Grille 17 and Grille 21 depending on what weapon was mounted inside the vehicle. The German word Grille means ‘cricket’ and the letter ‘e’ at the end is pronounced as an ‘er’: Grill-er.
The proposal was submitted on 6 May 1942 to the Wa Prüf 4 artillery division of the Heereswaffenamt (HWA) (German High Command’s center for technical weapons development). Krupp was authorized to build a single prototype with a completion date of 1 November 1942. The Wa Prüf 4 made a requirement that the vehicle must have the ability to have a 360-degree traverse. They also wanted it to be available for coastal defense work if necessary.

The Grille 17/21 chassis was much longer than a standard Tiger tank and difficult to photograph at close quarters. This image has been made by ‘stiching’ together a number of separate images. (The Tank Museum Bovington)

Design and Problems

The two guns were too heavy to be mounted in a turret so the Krupp design team had to find another solution. They constructed a large heavy circular base plate that would be carried at the rear of the vehicle and lowered into position when needed. The SPG would then drive onto the metal plate and could swivel on its tracks to point the gun at the target. This was an unusual design feature of this weapon system not seen on any other German vehicle in WW2.
Another requirement was that the guns were to be dismountable. This would be achieved by driving backward towards the base plate, after which the gun could be slid out of the vehicle and mounted on the base plate, allowing it to cover 360°. The reasoning behind this feature was that the Grille was also meant to be used in the coastal defense role and this allowed it to fire in any direction. This requirement was dropped in 1944 under the orders of Heinrich Himmler.
Design and mechanical problems were also encountered with the Tiger chassis, engine and transmission. It did not help that the winner of the competition between the Porsche and the Henschel designs hadn’t yet been decided, and they had vastly different drivetrain arrangements.

This American officer is examining the engine bay of the Grille 17/21 chassis. His presences gives you the sense of proportion of this weapon. It was very large. (The Tank Museum Bovington)
Initially, the vehicle was meant to have a 30 mm armor plate on the front of the chassis and 16 mm on the sides. In November 1942, it was decided to use SM-Stahl (carbon steel) in the construction of this self-propelled gun. 50 mm of SM-Stahl carbon steel were used for the front of the vehicle. The sides and rear would have 30 mm SM-Stahl carbon steel. This added to the weight of the vehicle. There were a number of delays in the project. The original 1 November 1942 completion date passed without a prototype being finished.
When the Panzer VI Ausf.B Tiger II (Sd.Kfz.182) heavy tanks started rolling out of the factory doors, Krupp decided to use the Tiger II engine, suspension, steering, and transmission instead of Tiger I parts. These components were not ready for delivery until January 1944. This delayed the estimated final construction of the prototype until the summer of 1944.
On 25 September of 1944, Reichsminister Albert Speer ordered a demonstration for Adolf Hitler to take place as soon as the vehicle was completed, now planned for the end of the year. Serial production was to then start at the rate of two per month.

This photograph was taken at the Henschel Panzerversuchsstation, Haustenbeck (Ordinance proving ground). Notice the armored hatches on the front of the Grille 17/21 SPG’s superstructure. (The Tank Museum Bovington)

Armament

It was envisaged that two different guns could be mounted in the vehicle: the 17cm Kanone K72 (Sf) L/50 or the 21cm Mörser 18/1 L/31. These two weapons were chosen because they used the same gun carriage and recoil system. The fittings would be the same when the guns were mounted within the self-propelled gun superstructure. The guns would have had a traverse of 5 degrees left and right from a fixed position. The gun sight was a Z.E. 34 with Rblf.36. Both vehicles would have to be supported by a number of ammunition carrying vehicles.

17 cm Kanone 18 in Mörserlafette on display at the U.S. Army Field Artillery Museum, Fort Sill, Lawton, Oklahoma, USA. (Jon Bernstein)
The Grille 17 would have carried 5 rounds plus propellant on board when equipped with a 17cm Kanone K72 (Sf) L/50 gun. It could fire two types of shells, the 68 kg Sprenggranate(HE) with 29.15 kg of propellant and a range of 28,000 meters and the 62.8 kg Sprenggranate(HE) with 30.5 kg of propellant and a range of 29,600 meters.
The 21cm Mörser 18/1 L/31 was already in production and use by the Germans when the project started. It was produced to replace the much older 21cm Mörser 16. The 21cm Mörser 18 replaced the 21cm Mörser 16 in front-line service around 1940 with the older gun being relegated to secondary theaters and training units. More than 711 21cm Mörser 18 guns were produced in 1939–45. The Grille 21 would have carried 3 rounds plus propellant on board when equipped with this gun. It could fire a 113 kg Sprenggranate(HE) shell with 15.7 kg of propellant to a range of up to 16,700 meters.

A 17 cm (172 mm) gun barrel and breach can be seen on the floor in front of a gun carriage with 21 cm Mrs 18 painted on it. The fate of the gun is not known.
In January 1945, plans were made to mount a 30.5cm caliber smooth bore mortar with fin-stabilized projectiles, due to the concerns over the length of time it took to produce artillery barrels for the two other guns. Krupp and Skoda both competed on this project with Skoda producing a 30.5 GrW L/16 prototype by April 1945.
As a side note to armament, in 1945 Kurt Arnoldt, Chief Engineer at Henschel, said in a 1945 interview that the 21cm gun produced too much recoil for the chassis as designed, making it impossible to fire from the chassis. The 17 cm muzzle break was based on a design by Solothurn design. Ammunition would have been stowed both in the vehicle and in wicker baskets on the side of the vehicle as well as in a following 18-ton semi-tracked vehicles (half-track). The gunnery sights also allow for direct firing of the gun on close-range targets.

German 21 cm Mörser 18 on display at the U.S. Army Field Artillery Museum, Fort Sill, Lawton, Oklahoma, USA. (Jon Bernstein)

Crew members

According to a British intelligence report from 1945, the Grille designs meant to have a crew of 8, composed of a driver, a commander and 6 gun crewmen. The loading of the two-part ammunition was meant to be done manually. It is stated in a 1945 interview with Kurt Arnoldt, the Chief Engineer for Henschel, that the additional crew would travel in a semi-track vehicle, Kurt Arnoldt suggests the 18-toner, and haul additional ammunition.

Mobility

A Tiger II Maybach HL 230 P30 V-12 water-cooled petrol 690 hp engine was ordered along with a Maybach OG 40 12 16 B gearbox with eight forward and 4 reverse gears. Henschel made the L 801 steering unit. The engine was mid-mounted in the chassis to allow for the maximum amount of room for the large gun and space for the crew.
As rubber was difficult to obtain in 1944 the wheels were 80 cm all steel tires. However, the 1945 interview with Kurt Arnoldt suggests rubber rimmed roadwheels. But photos do not confirm this. It was fitted with Gg 24-800/300 Tiger II track for traveling cross country, but this would have been replaced with smaller width Gg 24-600/300 Panther II tank track if transportation by rail was required.

A Troubled End

More delays occurred when the Allied air force bombed Krupp’s manufacturing plant in Essen. Construction work on the prototype was no longer viable at this location. On 7 December 1944 Krupp reported that the chassis was ready to be loaded onto a flat back railway wagon for transportation from Essen to the Henschel Panzerversuchsstation 96, Haustenbeck near Paderborn. It was recorded as being at this establishment on documents dated 22 December 1944 but missing many of the components needed for the completion of the project including the cooling and fuel system, Gg 24/800/300 tracks and hardened road wheel arms.
The Grille 17/21 prototype was still in an unfinished condition when the German High Command ordered all future work on the program to be stopped. The situation in the 1st quarter of 1945 was such that in their view there would not be any significant advantage in the completion of the project. Resources were limited and they had to be channeled to more important weapon production lines.
In 1945, the US 3rd Army captured the Henschel panzerversuchsstation, Haustenbeck Ordinance proving and tank testing ground in Northern Germany, 50 km south west of Hanover. A selection of German heavy tanks and self-propelled guns were found in working condition. A few prototype vehicles were discovered that never entered production. These included a partially assembled Geschützwagen Tiger für 17 cm Kanone 72 chassis and nearby a 17 cm Kanone 72. They did not find a second chassis or a 21 cm Mörser.

Gallery

The Allies took the chance to examine this huge weapon system. The three soldiers inside are dwarfed by the sides of the superstructure of the Grille 17/20 SPG. (The Tank Museum Bovington)

The driver sat on the left of the Grille 17/21 at the front. The hull machine gunner sat on his right, (The Tank Museum Bovington)

Here you can see the design of the extended chassis and the rear of the superstructure. Notice that it was an open topped SPG. (The Tank Museum Bovington)

The Jagdtiger SPG was 2.8 m (9 ft 2 in) tall and 10.65 m (34 ft 11 in) long. It gives you a good idea of how large the Grille 17/21 self-propelled gun was when the two vehicles are seen together. (The Tank Museum Bovington)

The front armor of the superstructure was only 30 mm thick. It was not enough to save the crew from a Soviet, British or American armor piercing AP round in 1945. (The Tank Museum Bovington)

The gun chassis rails can be seen on the floor of the fighting compartment in this photo of the Grille 17/20 SPGs fighting compartment. (The Tank Museum Bovington)

large perforated muzzle brake found next to the Grille 17/21 17 cm gun barrel. (The Tank Museum Bovington)

Wrong photos

The following photographs are often seen in books and posted on the internet wrongly claiming that they are photographs of a wooden mock-up of the Grille 17/21 fighting compartment. This is a mock-up of the Flakwagen auf Panther NOT the Grille 17/21. The first author to make this understandable error was Spielberger in his book ‘Tiger und seine Abarten’.

This is a photo of a mock-up of the Flakwagen auf Panther NOT the Grille 17/21 (Spielberger)

Wooden mock up of the superstructure of the Flakwagen auf Panther NOT the Grille 17/21 (Spielberger)

Gunners seat mock-up in the Flakwagen auf Panther NOT the Grille 17/21 (Spielberger)

An article by Craig Moore and CaptainNemo

Grille 17/21 specifications
Dimensions (L,W) Grille 17	13 m (42 ft 8 in), 3.27 m (10 ft 9 in
Dimensions (L,W) Grille 21	11 m (36 ft 1 in), 3.59 m (11 ft 8 in)
Height (17 & 21)	3.15 m (10 ft 4 in)
Total weight	60 tonnes (59 tons)
Crew	8 (Commander, driver, 6 gunners)
Propulsion	Maybach HL 230 P30 V-12 23 liter water-cooled petrol 690 hp engine
Top road speed	45 km/18 km (28 mph/11 mph)
Operational range (road)	250 km/125 km (155 miles/78 miles)
Main Armament	17 cm K72 L/50 or 21 cm M18/1 L 31 mortar
Armor (chassis)	16 – 30mm

Sources

Joachim Engelmann, German Heavy Field Artillery 1934-1945.(Schiffer Publishing Ltd)
Ian V. Hogg, German Artillery of WW2. (Pen & Sword)
Frank V.de Sisto, German Artillery at War 1939-45 vol.1. (Concord Publication Co).
Gordon Rottman, German self-propelled guns. (Concord Publication Co).
Peter Chamberlain, Thomas L.Jentz and Hillary L.Doyle, Encyclopedia of German tanks of WWII, (Arms and Armour Press).
Peter Chamberlain and Hillary L.Doyle, Profile AFV Weapons 55 German Self-Propelled Weapons. (Profile Publications)
The War Office, Handbook of Enemy Ammunition Pamphlet No 15 – 24th May 1945.
SHAEF, Restricted July 1944 – Allied Expeditionary Force – German Guns – Brief notes and range tables for allied gunners. SHAEF/16527/2A/GCT.
SHAEF, Allied Expeditionary Force German Guns – Brief Notes and Range Tables for Allied Gunners – SHAEF/16527/2A/GCT July 1944
Major L.J.McNair, Artillery Firing, (US Army, Fort Leavenworth, Kansas Oct 1919
U.S. Army Council. Handbook of Enemy Ammunition Pamphlet No.15. German Ammunition Markings and Nomenclature.
Panzer Tracts No.10 Artillerie Selbstfahrlafetten by Thomas L.Jentz and Hilary Louis Doyle
https://warspot.ru

Geschützwagen Tiger für 21 cm Mörser 18/1 (Sf.) Grille with the 21 cm Mortar fitted. It is painted in factory fresh Red-Oxide Primer. The length of the gun is noticeably smaller that the 17 cm cannon. The turning dish has not been fitted to the rear of the vehicle.

Geschützwagen Tiger für 17 cm Kanone 72 (Sf.) Grille with the 17 cm gun fitted in fictional ‘what if’ markings. Notice the extended chassis and the large turning dish mounted at the rear.

Both illustrations made by tank encyclopedia’s David Bocquelet

German Self-Propelled Artillery Guns of the Second World War

By Craig Moore

One towed artillery gun required a team of six horses and nine men. WW2 German engineers came up with the idea of mounting an artillery gun on top of a tank chassis. This new technology reduced the amount of resources required to deploy one artillery gun. Artillery self-propelled guns only needed a four or five man crew. They could also be made ready to fire more quickly. This book covers the development and use of this new weapon between 1939 and 1945. One type was successfully used in the invasion of France in May 1940. More were used on the Eastern Front against Soviet forces from 1941 until the end of the war in 1945.

Buy this book on Amazon!

WW2 German SPG Prototypes

German Tank-based Railway Guns

Post author By Harold Biondo
Post date September 27, 2017
23 Comments on German Tank-based Railway Guns

German Reich (1942-1944)
Self-Propelled Superheavy Siege Guns – None Built

“It seemed like a good idea at the time”

Times of war can lead to unorthodox solutions to unforeseen problems. Sometimes these are successful; the Duplex Drive tank, the jet engine, night vision, and reactive armor. Sometimes these aren’t so successful…
The designs talked about here are not among the former. This article is a collection of little-known projects by Nazi Germany to mount naval artillery, super heavy siege cannons, and railway guns on the combined chassis of two or more tanks. These designs are quite obscure and do not have enough information to warrant their own individual articles.

Tiger H als Tragfahrzeug für schwerste Geschütze

In January 1941 (perhaps this was a typo for 1942, as the project is only mentioned again in December of 1942, nearly two years later), the Waffenamt (German Army Weapons Agency) put out a requirement for a system for transporting the 24 cm Kanone 4.
The K 4 was a project to upgrade the underwhelming 24 cm K 3. Only 14 K 3 guns were built; the reason being was that they were much more time-consuming to set up and operate than comparable guns such as the 21 cm Mörser 18, while their advantage in performance was not significant enough to warrant the hassle. Little information is available on the K 4, other than basic measurements. The barrel length was a ‘L/72’ meaning it was 72 calibers long. (72 x 24 cm gives a total barrel length of 17.28 m) and the gun was meant to fire 160 kilograms (353 lb.) shells up to 49 kilometers (30.4 miles).
Both the firms of Krupp and Rheinmetall-Borsig responded to the requirement. Krupp’s design was to use two unarmored Panzer VI Tiger chassis; while Rheinmetall’s design used the Karl-Gerät chassis. Further information on Rheinmetall’s design is unavailable; presumably, it was rejected early on due to the Karl Gerät chassis being too slow and unmaneuverable.
On the 17th of December, 1942, the OKH (German Army High Command) sent letter Wa J Rü (WuG 6) Villa2 Nr. 9846/42 to Henschel, the manufacturer of the Tiger chassis, requesting the necessary parts to build a prototype. Assembly of the vehicle was to take place at one of Krupp’s plants. The order was signed under the name “Tiger H als Tragfahrzeug für schwerste Geschütze”, or “Tiger H as a carrier for the heaviest guns”.
Krupp’s design aimed to have greater speed and mobility than the lackluster Karl Gerät. The unarmored Tiger chassis weighed 25 tons each. In order to prevent one tank moving while the other wasn’t, which would have damaged the machine, the drive units of each chassis were intended to be hydraulically linked to stay at the same speed. The projected top speed was 30 to 35 kph (18.6 to 21.7 mph). Hydraulic jacks were to be installed in place of the turret in the Tiger chassis; these would support large cylinders which in turn supported the gun platform. The gun platform could be lowered onto its base plate and the Tigers driven away with minimum difficulty. Four outriggers would be deployed to stabilize the gun. Whether or not the gun had any reasonable degree of traverse once in firing position is unknown.
The gun platform was lowered in the center, like a heavyweight railroad flatcar, but even so, the assembly was more than twice as tall as a normal Tiger tank when in transport configuration. Additionally, the ground pressure for each unarmored unit was significantly higher than a normal Tiger tank. However, being too heavy to cross bridges was not seen as a concern as only one load-bearing unit would be on the bridge at one time, due to the vehicle being so long. The distance between the centers of the Tiger chassis was to be 20 to 22 meters (65.5 to 72.1 feet), to give a sense of scale, a normal tractor-trailer truck trailer is 53 feet, or 16.1 meters long.
On the 23rd of December, 1942, Henschel stated that they would be unable to produce more Tiger chassis for a Lastenträger vehicle alongside of normal Tiger production, as they were already at full capacity.
A single prototype of the K 4 was being constructed at Krupp of Essen, but this was destroyed in a bombing raid in March 1943. With the destruction of the prototype, the K 4 project was canceled. If it had not been canceled already, this was surely the death of the Tiger H als Tragfahrzeug für schwerste Geschütze as well.

24 cm Kanone 4 mit Lastenträger Tiger I (Drawing Copyright Hilary Louis Doyle)

Gerät 566 Lastenträger 606/5 für K 5/3 (Tiger)

As the first design was canceled due to the discontinuation of the intended weapon, and not because it was ridiculous and impractical, Krupp decided to persevere with the tank-based railway gun idea using the 28 cm K 5 instead. The K 5 (sometimes incorrectly referred to as Leopold – this was the name of an individual railway gun rather than the name for this system) was the most successful railway gun of World War II; 25 pieces were built in total. The railway version of the gun weighed 218 metric tons; this number is probably not far off from the weight of the tank-based gun had it been built.
To transport the K 5 Krupp chose the Panzer VI Tiger II chassis. The general construction was similar to that of the first design, however, it seems the second design had even thinner support cylinders. Coupled with the immense weight of the K 5, it is even more unlikely the mechanism for raising the gun into transport position and lowering the gun into firing position would be functional and reliable.
Note: The book ‘Der Panzerkampfwagen Tiger und Seine Abarten’ (Spielberger, 1997) seems to suggest that the gun barrel, gun carriage, and base plate were all transported separately. However, the same book shows the illustration below, which implies that the whole assembly was transported as a single unit. Transporting the weapon in pieces would help overcome the problems of its great size and weight, but would make assembly upon arrival a nightmare. The book also states that a separate Tiger II-based vehicle would bring along “closing pieces” for the gun.
The Gerät 566 Lastenträger 606/5 für K 5/3 (Tiger) would have used a late-war development of the K 5 gun; the K 5 Glatt. The K 5 Glatt had a 31 cm smoothbore gun tube that was designed to fire 136 kilograms (300 lb.) subcaliber fin-stabilized rounds called Pfeilgeschoß up to a range of 120 to 150 kilometers (74.5 to 93.2 miles). This was great enough range to fire on London. However, due to the implementation of the V1 ‘Buzz Bomb’ and V2 missile, the K 5 Glatt fell by the wayside. Only two were built, both in railway configuration.

28 cm Kanone 5 mit Lastenträger Tiger II (Drawing Copyright Hilary Louis Doyle)

28 cm DKM 44 auf Panther Langholzprinzip

This design comes from a drawing dated from September 1943, wherein Rheinmetall-Borsig proposed that two Panzerkampfwagen Panther chassis be used to transport their 28 cm Düsenkanone Marine (DKM) 44 recoilless coastal defense gun, then under development in Sömmerda for the Kriegsmarine.
The 28 cm DKM 44 was the largest recoilless cannon being developed in Germany at the time. Rheinmetall-Borsig was the primary, possibly only, firm conducting work on recoilless guns in the later half of the War. They were under contract by the Luftwaffe, Heer (Army), and Kriegsmarine to develop different calibers of recoilless guns for various uses. The two projects Rheinmetall-Borsig was working on for the Kriegsmarine were the 8,8 cm DKM 43, a cannon for small vessels that would normally not mount larger weaponry than machine guns, and the 28 cm DKM 44, a coastal defense gun to defend against enemy landing forces.
The 28 cm DKM 44 would have weighed 28,000 kg (28 metric tons), it had 10 degree barrel rifling, and an electrical ignition system. It was designed by Herr Osthues, and the ballistician for the gun was Engineer Weber. A prototype of the DKM 44 was apparently completed before the end of the war by Hanomag in Hanover, and had even undergone tests. Photographs and blueprints should exist for this gun, but as yet they have not been found.
It is not known where the idea to transport the gun with two Panther chassis originated, whether from Rheinmetall-Borsig or suggested by the Kriegsmarine. More likely it was the former, as the Kriegsmarine, with the exception of their other project on this page, the NM, normally had no involvement with tanks.
The name of Rheinmetall’s design was the 28 cm Düsenkanone auf Panther Langholzprinzip, which translated to English means 28 cm Recoilless Cannon on Panther Long Wood Principle. “Langholzprinzip” is the German term for the practice used in logging whereby fallen trees are attached to a truck at one end and to an independent set of trailing axles at the other. By doing this the logs are allowed to support themselves between the axles and negate the need for a trailer. This same principle was employed on the 28 cm Düsenkanone auf Panther, with one tank taking the place of the truck, and the other taking the place of the trailer, leaving the payload slung between them.
The first Panther had a support that would attach to a collar half-way up the 28 cm DKM 44’s barrel, while the second Panther had a large, crane-like structure that would hold the gun’s breech from above. In order to fire, the gun would be lowered to the ground by large hydraulic rams inside the hulls of the tank chassis. The Panthers would then disconnect from the gun and move away. The cannon could then be used as a normal gun emplacement, able to rotate on its pedestal. Inside the gun’s superstructure was stored 10 two-piece rounds.
There is no surviving evidence if this design was accepted to be the main mode of transporting the DKM 44, however there are very few alternatives for moving such a big gun. Nevertheless the War did not progress in Germany’s favor; the DKM 44 never became operational, and its function as a coastal defense gun was no longer needed.

28 cm DKM 44 auf Panther Langholzprinzip Blueprint Source

Epilogue

Nazi Germany is remembered, among other things, for hideously impractical, ludicrous ‘wonder weapons.’ The idea of making railway guns mobile by sticking multiple tanks together is probably one of the weirdest. In the end even the Nazis had enough sense to see that these designs were hopelessly impractical.
However designs for vehicle-based super heavy siege guns did go on, with such things as the 58 ton Grille 17/21, the 182 ton R 2, and the 1,000 ton Urling. None of these designs made any impact on the course of the war; only the Grille 17/21 was partially built while the others remained on paper. The only design of this type to become operational, the Karl Gerät, remains a lasting symbol of Hitler’s megalomania and the embracing of unconventional designs by the Third Reich’s war machine.

Sources

Les Armes secrètes du IIIe Reich: Hitler aurait-il pu gagner la guerre? – Laurent Tirone, 2014
Enzyklopädie Deutscher Waffen 1939-1945: Handwaffen, Artillerie, Beutewaffen, Sonderwaffen Gebundene Ausgabe – T.J. Gander and Peter Chamberlain, 2008
Der Panzerkampfwagen Tiger und Seine Abarten – Walter J. Spielberger, 1997
Panther Variants 1942-1945 – Osprey New Vanguard, 1997

Germans Tanks of ww2

Tank Encyclopedia’s own illustration of the 28 cm DKM 44 auf Panther Langholzprinzip by Jaroslaw Janas.

WW2 German SPG Prototypes

Waffenträger Panthers – Heuschrecke, Grille, Skorpion

Post author By Harold Biondo
Post date September 6, 2017
31 Comments on Waffenträger Panthers – Heuschrecke, Grille, Skorpion

German Reich (1942-1945)
Self-Propelled Guns / Weapon Carriers – Several Wooden Mockups Built

Animal Farm

In early 1942 Wa.Prüf 4, the German organization in charge of field artillery, put forward a design requirement for a vehicle to move heavy artillery. The main stipulation was that it should use parts from the new Panther medium tank. A similar competition was already underway for a vehicle to move lighter field artillery, such as 10.5 cm guns, using the Geschützwagen III/IV chassis. This had inspired Wa.Prüf 4 to do the same for a vehicle to move heavier 12.8 cm and 15 cm artillery pieces, as the Geschützwagen III/IV was too small to handle them. The guns in question were the 12.8 cm K 43 and 15 cm sFH 43. The sFH 43 (schwerer Feld Haubitze, heavy field howitzer) was a projected improvement on the 15 cm sFH 18, the new gun was to use bagged propellant and had a screw-type breech. The 12.8 cm Kanone 43 is unknown in most literature but is presumably a predecessor to the 12.8 cm K 44 L/55. Neither of these cannons were ever built.

In order to keep weight down, the designs were to be open-topped. Prototypes were to be built using Panther parts, but it was projected that any serial production vehicles would be made using the Panther II chassis. This idea was discarded when the Panther II was cancelled in June of 1943. Both Krupp and Rheinmetall-Borsig took part in this design competition. All designs were able to be transported by rail with a few adjustments, and all could carry at least 30 rounds, however, Rheinmetall’s design had trouble with this.

Despite these vehicles being colloquially known as waffenträgers, very few designs carried the name waffenträger in their designation. Despite “waffenträger” literally meaning “weapon carrier”, most German weapon carriers were called Selbstfahrlafette, meaning “self-propelled gun carriage”.

Krupp’s Cricket – (Sfl.) Krupp I and II

Krupp immediately set to work and on July 1st, 1942, came up with the 12.8 cm K 43 (Sfl.) Krupp I (indexed Gerät 5-1211) and 15 cm sFH 43 (Sfl.) Krupp I (indexed Gerät 5-1528). Both vehicles were nearly identical, only differing in armament. Both vehicles had a dismountable, 360-degree rotating turret and muzzle brakes on their cannons. The 15 cm sFH 43 (Sfl.) Krupp I’s 15 cm sFH 43 L/35.5 had a range of 18 km (11.18 miles). The chassis was called Bauelemente Fahrgestell Panther, literally “components of the Panther chassis.” No blueprints of these vehicles survive, leaving their appearance a mystery.

Shortly after designing the first vehicles, Krupp produced another version, the (Sfl.) Krupp II. Again, the 12.8 cm K 43 (Sfl.) Krupp II and 15 cm sFH 43 (Sfl.) Krupp II were identical except for armament. This second design also had a fully traversable dismounting turret. The chassis was also lengthened slightly, giving a wheelbase of 4,200mm. A full-scale wooden mockup of the 12.8 cm version was built in November 1942 and shown to Wa.Prüf 4 in January 1943. At this time Krupp stated they could have a working prototype ready by the 1st of September if they received the needed Pather components by the 1st of May, 1943.

12.8 cm K 43 Selbstfahrlafette Krupp II/Grille 12 (Drawing Copyright Hilary Louis Doyle)

15 cm sFH 43 Selbstfahrlafette Krupp II/Grille 15 (Drawing Copyright Hilary Louis Doyle)

Grille 12 Wooden Mockup

On the 18th of February, 1943, an order was placed for the construction of two (Sfl.) Krupp I prototypes; one 12.8 cm and the other 15 cm. On February 24th, 1943, Wa.Prüf 4 informed Krupp of the cover names that were assigned to their projects. The (Sfl.) Krupp I was named Heuschrecke (Grasshopper), and the (Sfl.) Krupp II was named Grille (Cricket).

These blueprints, from November 25th, 1942, show the existing Grille 15 design on top, and on the bottom show an improved version proposed on the 11th of November. The November 11th design has the fighting compartment 15mm lower and slightly forward than that of the existing design, it is also equipped with a new type of muzzle brake. Whether or not this proposal was incorporated into the Grille 15, we do not know at this time. Source

This set of blueprints show the process by which the gun assembly would be dismounted. The vehicle’s gun barrel would be used as a jib. A block and tackle would be attached to allow it to lift the metal frame pieces off the front of the hull and put them in position behind the turret; forming a ramp. Wheels would be attached to the turret pedestal, and a winch on the hull would lower it down the ramp. Once off the vehicle, support legs could be attached to the turret pedestal allowing it to be used as a field gun. Overall a quite complicated process. Source

On the 11th of March, 1943, due to concerns that production of the new 15 cm sFH 43 would be slow, Wa.Prüf 4 requested that the option of mounting the older 15 cm sFH 18 on the Grille 15 be looked into. By April 20th it was determined that utilizing the sFH 18 would cause too many problems. Instead, development went ahead using the 15 cm sFH 43, incorporating as many parts from the 15 cm sFH 18 as possible.

On April 3rd, 1943 Wa.Prüf 6 (the German organization in charge of military vehicles) stepped in and told Krupp they were only allowed to build a prototype of the Grille. On the 5th of May 1943, Krupp informed Wa.Prüf 6 that the February 8th order for two Heuschreckes had been canceled.

On the 21st of May, 1943, Maschinenfabrik Augsburg Nürnberg (M.A.N.), the company producing the Panther, was told to manufacture a complete set of suspension components, engine, transmission and drive train, as well as driver’s periscope and telescoping air intake for Krupp’s Grille prototype.

On June 7th, 1943, Krupp reported that a 1:10th scale mockup of the Grille would be ready by about mid-July, and a full-size prototype by the 1st of November. At an unknown date the 12.8 cm K 43 cannon was changed to a 12.8 cm K 44 L/55 with conventional breach; the 15 cm sFH 43 as well now had a conventional breech instead of a screw-type breach.

By the 20th of October, 1943, Krupp had failed to produce a prototype. Wa.Prüf 4 saw the project as going nowhere and ordered Krupp to stop all work on the project. Krupp did stop work on the Grille and Heuschrecke, but continued to design Panther-based weapons carriers.

Grille Design from January 18th, 1943 (Drawing Copyright Hilary Louis Doyle)

If at First You Don’t Succeed… – Selbstfahrlafette mit Absetzbarer 15 cm sFH 18

On January 20th, 1944, Krupp produced drawing SKA 879 for the Selbstfahrlafette mit Absetzbarer 15 cm sFH 18 (Self-propelled vehicle with dismountable 15 cm sFH 18). The vehicle was basically a normal Panther chassis with a wheelbase of 3,920mm; however, the rear of the hull was lengthened slightly to support a rear mounted artillery turret. The turret rested on a metal box; the turret and box forming the fighting compartment. Using metal beams apparently attached to the idler wheel, the entire assembly could be lifted up and off the vehicle by driving a few feet in reverse. Once off the chassis, the gun assembly could be used as a standalone artillery piece.

On February 3rd, 1943, Krupp presented a second design with drawing SKB 891. This version had the turret centrally mounted with the engine in the rear. The turret, which looks remarkably similar to that of the Heuschrecke 10, was lifted off over the front of the tank in the version 2, as opposed to over the rear as in the version 1. A wooden mockup of the Selbstfahrlafette mit Absetzbarer 15 cm sFH 18 version 2 was built, but neither design progressed past this point.

A conceptual model of the Selbstfahrlafette mit Absetzbarer 15 cm sFH 18, for unknown reasons, the chassis is not that of a Panther. Perhaps originally it was intended to use a custom chassis. This design has often been misidentified as the Heuschrecke 15.

Selbstfahrlafette mit Absetzbarer 15 cm sFH 18 Version 1 (Drawing Copyright Hilary Louis Doyle)

Selbstfahrlafette mit Absetzbarer 15 cm sFH 18 Version 2 Wooden Mockup

Skorpion of the Rhein – (Sfl.) Rheinmetall-Borsig

Like Krupp, Rheinmetall-Borsig also presented their first designs on the 1st of July, 1942. They were the 12.8 cm K 43 (Sfl.) Rheinmetall-Borsig (indexed Gerät 5-1213), and 15 cm sFH 43 (Sfl.) Rheinmetall-Borsig (indexed Gerät 5-1530). The vehicles were identical except for armament. Both had a 360-degree rotating turret and a hydraulic gun dismounting mechanism designed by Daimler-Benz, similar to that used on the Heuschrecke 10.

The 12.8 cm version was armed with a 12.8 cm K 43 L/51 with no muzzle brake. It fired a 28 kilogram projectile at 850 meters per second (2,789 ft/s), at a maximum range of 22 km (13.67 miles). The gun assembly for this version weighed 6.2 metric tons; the total weight of the vehicle was about 38 metric tons. The 15 cm version was armed with a 15 cm sFH 43 L/32.5; identical to the gun used on Krupp’s design except that Rheinmetall’s had no muzzle brake. The armament weighed 8.2 metric tons and consequently left the vehicle weighing 40 metric tons – 2 tons more than the 12.8 cm version. A prototype for each was expected to be ready by Summer 1943.

Rheinmetall’s design was seemingly met with little enthusiasm; Krupp’s Grille was the clear favorite. Despite the design not having been rejected, Rheinmetall chose to drop their original entry and proceed with another design.

12.8 cm K 43 Selbstfahrlafette Rheinmetall-Borsig – please note the end of the barrel has been cropped off in this image. (Drawing Copyright Hilary Louis Doyle)

15 cm sFH 43 Selbstfahrlafette Rheinmetall-Borsig (Drawing Copyright Hilary Louis Doyle)

On January 7th, 1943, Rheinmetall produced three more designs. In reality, these were the same vehicle, but with different armaments. The vehicles had centrally mounted, 360-degree rotating, dismountable turrets. The chassis was that of a Panther, extended to a wheelbase of 4,220mm.

Drawing H-SkB 80449 for 15 cm sFH 43 (Sfl.) Rheinmetall-Borsig
Drawing H-SkB 80450 for 12.8 cm K 43 (Sfl.) Rheinmetall-Borsig
Drawing H-SkB 80451 for 12.8 cm P 43 (Sfl.) Rheinmetall-Borsig

This version of the 15 cm sFH 43 (Sfl.) had a slightly longer gun barrel at L/34. It fired a 43.5 kilogram projectile at 600 meters per second (1,968.5 ft/s) up to 15 km (9.32 miles) range. The 12.8 cm P 43 was a high-performance (presumably) dedicated anti-tank gun. It fired a sub-caliber 14 kilogram (31 lb) shell at 1,175 meters per second (3,855 ft/s). Rheinmetall said they could have a prototype ready by the 1st of August if they received the needed Panther parts by the 1st of April, 1943. A wooden mockup was built of one of the 12.8 cm-armed versions, but this design did not advance any further.

12.8 cm K 43 Selbstfahrlafette Rheinmetall-Borsig – January 7th, 1943 (Drawing Copyright Hilary Louis Doyle)

12.8 cm Selbstfahrlafette Rheinmetall-Borsig – January 7th, 1943 Wooden Mockup

On or around the 24th of February, 1943, Rheinmetall’s entry for the Selbstfahrlafette für 12.8 cm K 43 und 15 cm sFH 43 Project was assigned the cover name “Skorpion”. This name probably covered the January 7th design, but since it is not known when Rheinmetall abandoned it, it cannot be said for certain.

Unwilling to stop perfecting the design, Rheinmetall continued to design more versions. On the 2nd of April 1943, they produced drawing H-SKA 81959 for the 12.8 cm Skorpion mit Panther Bauteilen; and on April 16th drawing H-SKA 82566 for 15 cm sFH 18 mit Panther Bauteilen. These designs had a Panther-based chassis with a wheelbase of 4,025mm. Around the 20th of October 1943, Wa.Prüf 4 canceled the Grille, Heuschrecke, and Skorpion projects.

12.8 cm Skorpion mit Panther Bauteilen – April 2nd, 1943 (Drawing Copyright Hilary Louis Doyle)

15 cm Skorpion mit Panther Bauteilen – April 16th, 1943 (Drawing Copyright Hilary Louis Doyle)

Not Done Yet – 15 cm sFH 18 auf Panther Bauteilen

Despite the Skorpion project being canceled, Rheinmetall continued to make more vehicle proposals in the early part of 1944. These final designs shared the modified Panther chassis developed for the Skorpion. Drawing H-SKA 86187 from the 11th of January, 1944 was yet another proposal for mounting the 15 cm sFH 18 on a Panther-based chassis. An improved version of this design came on January 31st with drawing H-SKA 88200. At some point, the mounting of the gun was raised from 2,500mm to 2,750mm off the ground to allow greater elevation. Further details are unknown.

It seems that after this, Rheinmetall-Borsig stopped all work on Panther-based weapons carriers. If they did take part in the design competition for the July 6th, 1944 requirement; the design has been lost. However, it is more likely they did not; leaving Krupp the only entry.

H-SKA 88200 (Drawing Copyright Hilary Louis Doyle)

Round Two – Mittelerer Waffenträger sFH 18 auf Panther

Please note that the dates for this section are contradictory. Panther & Its Variants gives the date of the issuing of the Geschützwagen Panther für sFH 18/4 (Sf) requirement as February 11th, 1944; while Panther Variants 1942-1945 gives it as July 6th. July seems to be the correct date; it also comes from the more recent book. Strangely, one sentence in Panther & Its Variants says that the Gerät 811 was based on “AZ 735 Wa.Prüf 4/Is from July 6th, 1944.” This would seem to indicate that the Gerät 811 was an entry for the July 6th requirement; perhaps the authors did not realize this at the time. Very little is known about the Gerät 811, apart from the fact it was armed with a 15 cm sFH 18/4. It is plausible that Krupp’s Mittelerer Waffenträger sFH 18 auf Panther was assigned the designation Gerät 811, but that is just conjecture.

On the 6th of July 1944, Wa.Prüf 4 put out the Geschützwagen Panther für sFH 18/4 (Sf) requirement: a request for designs for a vehicle based on the Panther. In near identical repetition of the events two years prior, the requirements were that the vehicle carries a 15cm gun in a dismountable turret that could rotate 360 degrees. The 15 cm sFH 18 cannon was required to have no muzzle brake, as it was supposed to be able to fire Sprenggranate 42 TS sabot rounds. Without the muzzle brake, the force of recoil of the cannon was a massive 28 metric tons; this was deemed acceptable for the chassis.

Krupp was the only company to show interest; on the 16th of September 1944, they unveiled drawing Bz 3423 for the Mittelerer Waffenträger sFH 18 auf Panther. It had a hexagonal, forward mounted turret on a lightly armored Panther chassis. The turret rested on a round pedestal within the tank. To remove the turret assembly, the turret was traversed 90 degrees to the left. The left side panel was folded down, forming two guide rails running perpendicular to the tank. At the end of each guide rail was a vertical spar, reinforced to one another with crossbeams. Roller blocks with two wheels each were affixed to either side of the turret and allowed it to be hoisted up, presumably by hand, onto the guide rails, where it was free to roll. Exactly how the turret was then moved off the tank is unclear. This whole process is described only in “Panther & Its Variants”, which states that two block and tackles were used to lift the turret. These would require some type of overhead gantry, which, if correct, raises the question as to why hoisting the turret assembly onto guide rails first is necessary at all. Presumably, the Panther was then driven away and the turret assembly lowered to the ground.

However the dismounting process was intended; once the turret assembly was on the ground four outriggers, which were otherwise stored fore and aft of the turret on the tank’s hull, were attached to it. Wa.Prüf 4 required that the number of outriggers be changed to three, as this would lower the gun’s overall height and give the gun crew easier access.

Shortly afterward, on the 21st of September 1944, Krupp produced a second version with the turret mounted centrally. Along with the second version, Krupp also proposed a version armed with the 12.8 cm K 44 L/55 (with muzzle brake). The 12.8 cm version’s turret was longer and slightly taller.

Mittelerer Waffenträger sFH 18 auf Panther Version 2 – 15 cm Version (Drawing Copyright Hilary Louis Doyle)

Mittelerer Waffenträger K 44 auf Panther Version 2 – 12.8 cm Version (Drawing Copyright Hilary Louis Doyle)

Only one day later, on the 22nd of September 1944, Krupp representative Dr. Bankwitz met with Wa.Prüf 4 in Berlin. Despite the requirement for a weapons carrier being only two months old, Wa.Prüf 4 ordered Krupp to stop all work on these designs, as they were no longer needed and the Panther chassis was no longer to be used for such purposes.

Never Give Up, Never Surrender

Completely ignoring Wa.Prüf 4’s demands, Krupp produced drawing Bz 3445 on October 12th, 1944 for the Mittelerer Waffenträger sFH 18 auf Panther (dünnwandig) (dünnwandig means “thin-walled”). This was a lighter version of the Mittelerer Waffenträger sFH 18 auf Panther. It had thinner armor, carried only 50 rounds of ammunition instead of 60, and had a redesigned, cylindrical turret. These changed saved 7 metric tons of weight.

On the 25th of October 1944, the High Command General of Artillery suggested doing away with the requirement for a dismountable, 360 degree traversing turret for possible future weapons carriers. However, this was deemed necessary and the suggestion was declined. On the 23rd of December 1944, General Wolfgang Thomale requested that the High Command General of Artillery hold off on issuing another panther-based weapons carrier requirement, as Panther production numbers were lower than expected. Instead, he requested that they wait to see if the role could be fulfilled by the upcoming 38(d) platform.

Due to the situation of the War in late 1944 and 1945, surviving information on the remaining projects is highly fragmented.
A Directive dated November 19th, 1944, ordered the cessation of the Gerät 808 project, a Panther-based weapon carrier for the 15 cm sFH 18/2, due to the plans not being ready.
A telex message dated February 6th, 1945, stated that the chassis without turret that Krupp required for the Schwerer Panzerhaubitze was waiting at the steel works in Hannover.
A February 20th, 1945 report on the emergency situation of the War gave a list of projects that were to be immediately terminated. On that list was a 15 cm sFH 18 auf Panther Bauteilen.

Sources

Special Panzer Variants: Development – Production – Operations – Hilary Louis Doyle and Walter J. Spielberger, 2007
Panther Variants 1942-1945 – Osprey New Vanguard, 1997
Panther & Its Variants – Walter J. Spielberger, 1993

12.8 cm K 43 Selbstfahrlafette Krupp II/Grille 12 illustration by David Bocquelet

The same vehicle, but with the gun platform shield lowered. Illustration by David Bocquelet, modified by Freezer

Waffentrager 12.8 cm Skorpion mit Panther Bauteilen by Jaroslav Janas

12.8 cm K 43 Selbstfahrlafette Rheinmetall-Borsig. Illustration by David Bocquelet, modified by Freezer

Mittelerer Waffenträger sFH 18 auf Panther Version 2 – 15 cm Version. Illustration by David Bocquelet and Alexe Pavel

Germans Tanks of ww2

WW2 German SPG Prototypes

Raupenschlepper Ost Artillery SPG

Post author By Craig Moore
Post date March 11, 2017
7 Comments on Raupenschlepper Ost Artillery SPG

German Reich (1943-1944)
Self-Propelled Gun – 4 Prototypes Built

Weapon Carrier or SPG?

The German’s experimented with transporting and mounting a number of different guns on the back of the Raupenschlepper Ost light ‘prime mover’ tracked vehicle. The name Raupenschlepper Ost is translated to “Caterpillar Tractor East”. It is commonly abbreviated to just RSO.
The prototypes were shown to the army. The Raupenschlepper Ost 7.5 cm Pak 40 tank destroyer self-propelled gun went into production. Between 80 and 90 were produced. Most saw action on the Eastern Front. A version of the RSO that carried a 2cm Flak38 anti-aircraft gun mounted to the floor of the rear wooden cargo bay also saw service.
At present no documentation has been found relating to the mounting and carrying of artillery guns on the back of the Raupenschlepper Ost even though there are surviving photographs of four different prototypes: the 7.5 cm GebH 36 auf RSO/3; 7.5 cm Gebh 34 auf RSG; 10.5 cm GebH 40 auf RSO/1 and 15 cm sIG 33 auf RSO/3.
It is not clear if these prototypes were going to be used as a Waffenträger weapon carrier or as a Selbstfahrlafette Geschuetzwagen, a self-propelled artillery gun.

This is why a weapons carrier was a good idea. Towed guns could become waterlogged and covered in mud.
If they were used as a Waffenträger then how was the gun dismounted? There is photographic evidence that the guns were loaded on the vehicle by a winch attached to a freestanding metal frame on a hard surface. Another photograph shows a Raupenschlepper Ost reversed back towards an earthen ramp so the gun could be pushed onto the back of the vehicle.
On a battlefield, it would be difficult to build a ramp quickly or make sure there was a hard surface for a winch and frame to be constructed on to enable the guns to be unloaded. The guns were heavy and if the load bearing frame was put together on soft earth its legs would sink into the ground under the weight.
If these prototype vehicles were intended to be used as a Selbstfahrlafette Geschuetzwagen, or self-propelled artillery guns, the problem the engineers would have to overcome was the recoil.
With the artillery gun mounted in the back of the vehicle, they were very top heavy and had a high center of gravity. There was a danger that the RSO would topple over.
It can be theorized that two of the prototypes were intended to be used as artillery SPGs but tests showed the RSO chassis was not strong enough to take the gun recoil so they were never put into production. This is supported by the fact that on the photographs of the 7.5 cm GebG 36 auf RSO/03 the side panels are down and it can be seen that the gun wheels had been clamped to the deck of the vehicle and the gun ‘tails’ had been shortened. The 7.5 cm Gebirgshaubitze 34 auf Gebirgsraupenschlepper (RSG) also carried a similar sized howitzer.

7.5 cm GebG 36 auf RSO/3
The other two prototypes seen in photographs are carrying much bigger 10.5cm and 15cm howitzers. There is no evidence that these guns were bolted to the wooden cargo bay of the RSO tracked vehicle so that it could be fired. The gun’s split trail legs had not been modified to fit the length of the vehicle. They protrude out the back and the rear ‘spades’ are carried in the back of the vehicle for use when the gun is set up on land again. The RSO tracked vehicle is being used as a Waffenträger weapon carrier in these examples.

The Raupenschlepper Ost RSO tracked vehicle

The RSO light ‘prime mover’ tracked vehicle had a very basic suspension design with all steel wheels and just four small leaf springs. This made it cheap and easy to produce. It had high ground clearance and excellent performance in poor terrain. It was a tracked version of the Steyr 1½-tonne truck. It could carry a 1,500 kg (3,307 lb) load in its cargo bay.
The Steyr-Daimler-Puch manufacturing company designed the Raupenschlepper Ost (RSO) to be used to tow field guns and transport supplies over rough ground in muddy waterlogged and snowy conditions. They were in production between October 1943 and May 1944: Steyr-Daimler-Puch produced 2,600 vehicles; Klockner-Deutz-Magirus (KHD) manufactured 12,500; Auto-Union made a further 5,600 and Graf & Stift constructed 4,500 RSOs. They were used extensively on the Eastern Front.
There were four main variants. The RSO/01, RSO/02 and RSO/PaK40 were powered by a 3.5L Steyr V8 gasoline/petrol 70hp engine. The RSO/03 had a better performing Deutz F4L514 5.3L 4-cylinder air-cooled diesel engine although produced lower horsepower at 66hp.

RSO/01 towing a field gun
The RSO/1 had a fully enclosed pressed steel rounded cab with a wooden rear cargo bay. The RSO/2 had a flat sided metal cab. The RSO/3 was manufactured by KHD at their Magirus Factory and had a simplified slab-sided metal cab. The RSO/PaK40 had a lightly armored low profile steel cab to enable the 7.5cm PaK40 anti-tank gun mounted on the rear flat rear bed wooden cargo bay to fire forward.

RSO/3 fully tracked artillery prime mover

7.5 cm Gebirgshaubitze 36 auf Raupenschlepper Ost (RSO/3)

To mount the 7.5cm Gebirgsgeschütz 36 (7.5 cm GebG 36) light mountain howitzer on the back of the Raupenschlepper Ost tracked vehicle cargo bay the spades at the end of the split trail legs were removed. The legs were also cut down in length to allow the back tail gate to be raised. The wheels were bolted to the wooden floor in a special semi-circular frame. This gun was meant to be fired from the back of the RSO. It could no longer be dismounted and fired from the ground without having new split trail legs fitted. It could not function as a Waffenträger weapon carrier. It was a Selbstfahrlafette Geschuetzwagen, a self-propelled artillery gun prototype.

7.5cm Gebirgsgeschütz 36 (7.5 cm GebG 36) light mountain howitzer mounted on the rear of an RSO/3
The gun was built by Rheinmetall to replace the World War One mountain divisions (Gebirgs Divisionen) guns. Between 1938 and 1945, records show 1,193 were built. It was a standard German horizontal sliding breech block gun with a muzzle brake. It used a variable recoil system that shortened the recoil as the elevation increased to stop the gun breach hitting the ground. Rear trunnions were added to lengthen the distance between the breech and the ground. The recoil mechanism was hydropneumatic, with both buffer and recuperator positioned below the barrel.
To keep the weight down the gun was fitted with light-alloy disc wheels with rubber rims. No protective gun shield was fitted to save weight. It weighed 750 kg (1,650 lb) so it was within the cargo weight limit of the RSO.
When used on the ground, the 7.5 cm GebG 36 would jump when fired at low angles, because of its lightness. The strength of the recoil would force the gun’s trail spades to act as a fulcrum and lever the wheels upwards. The shell canister bag charge 5, the largest propellant increment, was forbidden to be used at near horizontal angles under 15° because the gun would jump excessively. When the gun was fired at higher angles it performed better as the ground absorbed any residual recoil forces not absorbed by the recoil system. On the back of the RSO the vehicles suspension, tracks and the ground had to absorb the force of the recoil from the gun.
The 7.5cm Gebirgsgeschütz 36 mountain howitzer used two-part ammunition, with four bag charges of propellant that were added together depending on the range of the target. A larger 5th charge bag was used on its own when the target was at the limit of the howitzers maximum range. It fired a high explosive HE 5.83 kilograms (12.9 lb) shell that had a maximum range of 9.25 km (10,120 yards). It could also fire smoke shells and in an emergency a hollow charge armor piercing AP rounds at short range. A good gun crew was able to produce a rate of fire of six to eight rounds per minute.
This mountain gun could be broken down into six separate parts, each having a maximum weight of 300 pounds. This ability enabled the weapon to be easily transported by pack animals or in an airplane.
The gun’s 56-inch barrel was of a monobloc construction. To enable larger more powerful charges to be used and to increase the range of the gun without damaging the gun barrel, it was fitted with a perforated, six-baffled muzzle brake.

7.5 cm GebH 36 auf Gebirgsraupenschlepper (RSG)

Gebirgsraupenschlepper (RSG) with a 7.5 cm Gebirgshaubitze 34 mountain howitzer mounted on its rear cargo bay next to a RSO/3 tracked vehicle.
This photograph shows the smaller Steyr made Gebirgsraupenschlepper (RSG) mountain troop tracked vehicle next to the larger Raupenschlepper Ost (RSO/3) vehicle. There is a 7.5 cm Gebirgshaubitze (GebH) mountain howitzer mounted on the back of the RSG. Only one photograph has been found so far of this prototype artillery self-propelled gun. The photograph below has been enlarged and edited.
The problem is that the caption that went along with this photo identified the gun on the back as a captured Belgian army Swedish-built Bofors 75 mm Model 1934 mountain gun (Canon de 75 mle 1934). It was recorded as a 7.5 cm Gebirgshaubitze 34 auf RSG, but this gun was not fitted with a circular perforated muzzle brake.
It can be theorized that the howitzer on the back is the same gun used on the 7.5 cm Gebirgshaubitze 36 auf Raupenschlepper Ost which does have a circular perforated muzzle brake. Just like on the other vehicle, it would have had its split tail legs cut to fit the length of the wooden cargo bay and the wheels clamped to the floor so that the gun could be fired from the back of the vehicle.

7.5 cm Gebirgshaubitze 34 auf Gebirgsraupenschlepper (RSG)

RSG – Gebirgsraupenschlepper – Caterpillar Tractor for Mountain Troops – Vienna Military Museum

Illustration of the sIG33 auf Raupenschlepper Ost conversion by David Bocquelet

10.5 cm Gebirgshaubitze 40 mountain howitzer on the back of a Raupenschlepper Ost (RSO/1)

7.5 cm Gebirgsgeschütz 36 German mountain howitzer

10.5 cm GebH 40 howitzer – Photo – Yuri Pasholok

The 15 cm sIG 33 (schweres Infanterie Geschütz 33) was the standard German heavy infantry gun used in the Second World War – unknown modeler

10.5 cm Gebirgshaubitze 40 auf Raupenschlepper Ost (RSO/1)

There is a poor quality photograph showing a 10.5 cm Gebirgshaubitze 40 (10.5 cm GebH 40) mountain howitzer on the back of a Raupenschlepper Ost (RSO/1).
In the picture, it looks like the vehicle has been backed up to ramp of earth. There appear to be wooden planks spanning the gap between the top of the earth mound and the back of the RSO/1. Its tail gate is hinged down and so are the wooden side panels. These wooden planks would have been used to enable the gun to be pushed onto the back of the vehicle.
RSO mit 10.5 cm GebH 40
10.5 cm GebH 40 auf RSO
Unlike on the photographs of the 7.5 cm Gebirgshaubitze 36 auf Raupenschlepper Ost (RSO/3), there is no visible evidence that the larger 10.5cm GebH 40 gun had been fixed to the wooden floor of the cargo bay. The split trail legs had not been cut and shortened. They projected over the rear of the vehicle.
There was no special semi-circular locking wheel frame in use. The spades that were normally fitted to the end of the split trail legs had not been attached. Their triangular shape can be seen at the back of the gun.
Was this photograph taken of an early live firing trial to see if the RSO/1 could take the gun recoil or just to see if it could take the weight of the gun? It is not known, as no documents have been found so far.
In the other surviving photographs the gun is seen on the back of the RSO/1 with the wooden side panels in the up position, the split trail legs sticking out the back and the tail spades loaded on the rear with the tail gate panel in the down position.

10.5 cm GebH 40 mountain howitzer on the back of a Raupenschlepper Ost (RSO/1)
The RSO/1 tracked vehicle has the manufacturing company’s name and logo on the side. This is a factory vehicle, not one that has been sold to the army. It is safe to assume that it is the company, Steyr-Daimler-Puch, who was experimenting with showing that the 10.5cm GebH 40 mountain howitzer can be transported on the back of their vehicle.

10.5 cm Gebirgshaubitze 40 (10.5 cm GebH 40) carried on the rear of an RSO/03.
In these three, better quality photographs it looks like a frame and winch had been used to lift the gun onto the back of the RSO/1. These photographs would suggest that this vehicle was being used as a Waffenträger weapon carrier. At present, there is no evidence to suggest the vehicle was used as a Selbstfahrlafette Geschuetzwagen, a self-propelled artillery gun, and fired from the back of the cargo bay, as there are no visible mountings or fixings to secure the gun to the vehicle.

10.5cm Gebirgshaubitze 40 mountain howitzer being loaded on the back of an RSO/1 by winch and frame
There only appears to be photographs of a 10.5 cm Gebirgshaubitze 40 mountain howitzer on the back of one RSO tracked vehicle. It is highly unlikely that the experiment was a success as the weight of the gun exceeded the designed load weight of the vehicle. The gun weighed 1,660 kg (3,660 lb) and the RSO’s load weight limit was 1.500 kg (3,307 lb). The RSO’s center of gravity would have been significantly raised. Both these things would have made the vehicle tricky to drive.

15 cm sIG 33 auf Raupenschlepper Ost (RSO/3)

15 cm sIG 33 auf RSO-03
15 cm sIG 33 auf Raupenschlepper Ost (RSO/3)
There is only one photograph currently available of a 15 cm sIG 33 (schweres Infanterie Geschütz 33), the standard German heavy infantry gun in WW2, loaded on the back of a Raupenschlepper Ost (RSO/3) tracked vehicle. The split trail legs can be seen sticking out the back of the vehicle. There had been no attempt to cut them to fit the length of the RSO/3’s wooden cargo bay.
This was not a test to see if the 15 cm sIG 33 howitzer could be fired from the back of the vehicle. The gun was too big and the RSO/3 would not have been able to handle the violent recoil. This vehicle was not a German Selbstfahrlafette Geschuetzwagen, a self-propelled artillery gun. It was almost assuredly a trial to see if the gun could be carried on the back of the RSO/3.
The experiment most likely failed, as the weight of the gun exceeded the designed load weight of the vehicle. The gun weighed 1,800 kg (4,000 lb) and the RSO’s load weight limit was 1.500 kg (3,307 lb). The RSO’s center of gravity would have been significantly raised. Both these things would have made the vehicle sluggish and difficult to maneuver. The RSO/3 was not a suitable vehicle to be a Waffenträger weapon carrier for the 15 cm sIG 33 howitzer.

Conclusion

The most plausible theory is that the Steyr-Daimler-Puch manufacturing company wanted to win a lucrative German government contract to build self-propelled artillery guns using their cheap to produce Raupenschlepper Ost light tracked vehicle and RSG. They exhibited four prototype vehicles that had different artillery howitzers mounted on the back to the government inspectors.
Two of the guns used were too big for the RSO tractor. The 7.5cm mountain howitzer was light enough and could be mounted to the floor of the wooden cargo bay at the rear of the RSO and RSG vehicles. These prototypes seemed viable as artillery SPGs.
At the time there was competition from other vehicle and arms manufacturers who wanted to win the same contract. Their designs used sturdier German tank chassis or captured enemy armored fighting vehicles on which to mount artillery guns. They won the contract, not Steyr-Daimler-Puch.

An article by Craig Moore

Specifications
Dimensions (L-W-H)	7.19 m x 3 m x 2.87 m (14ft 6in x 6ft 6in x 8ft 6in)
Total weight unladen	7,728 lb (3,505 kg)
Armament	7.5cm Gebirgsgeschütz 36
Track width	13 inch/24 inch with snow plates (33/61 cm)
RSO/1-2 Propulsion	3.5L Steyr V8 gasoline/petrol 70hp engine
RSO/3 Propulsion	Deutz F4L514 5.3L 4-cylinder air cooled diesel engine 66hp
Fording depth	34 inches
Top road speed	30 km/h (18 mph)
Operational range (road)	300 km (155 miles)

Sources

U.S. Office of Chief of Ordnance, 1945 Catalog of Enemy Ordnance
Weapons of the Thrid Reich by Gander and Chamberlin
German Artillery of World War Two by Ian Hogg
Marcus Hock

Germans Tanks of ww2

German Self-Propelled Artillery Guns of the Second World War

By Craig Moore

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WW2 German SPG Prototypes

10.5 cm leFH 18/6 auf Waffenträger IVb Heuschrecke 10

Post author By Craig Moore
Post date January 17, 2017
1 Comment on 10.5 cm leFH 18/6 auf Waffenträger IVb Heuschrecke 10

German Reich (1942)
Self-Propelled Gun – 1 or 3 Built

The Grasshopper

The German 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV ‘Heuschrecke IVb’ ‘Grasshopper’ was designated a weapon carrier (waffenträger) and not a self-propelled artillery gun. The reason for this is that the turret could be removed from the top of the modified Panzer IV tank chassis by a block and tackle rig attached to a movable metal frame.
The idea was that the gun crew could keep up with the armoured Panzer Divisions. When needed to fire as an artillery battery, to give long range support firing high explosive shells over the heads of the German infantry and tank crews, The gun would be removed and placed on the ground where it could be fired like a normal artillery gun.

The 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV ‘Heuschrecke IVb’ ‘Grasshopper’ artillery SPG prototype at the Krupp-Grusonwerks factory
The heavy lifting metal framework could be swung upright into position by a hydraulic system or a manual back up system. When not needed it was lowered down and stored on top of the upper track guards on both sides of the tank chassis.
The vehicle could carry 87 high explosive shells. If more were needed the turret could be removed and placed on a gun carriage and towed behind the tank chassis. This allowed for more ammunition to be carried onto the battlefield. The modified Panzer IV tank chassis became a turretless armoured ammunition carrier. This configuration would have only worked in gentle undulating countryside or on roads. The gun carriage wheels and frame were carried on the tank chassis at the rear.
The 10.5cm howitzer could also be fired from on top of the tank chassis. There was no top to the turret. There were a few disadvantages of an open topped vehicle. The crew was exposed to the elements and were also at risk of injury from enemy thrown hand grenades, mortars and shrapnel from air burst enemy shells. A canvas tarpaulin rain cover was produced.

The side and rear of the open topped turret could be folded down to give more room for the crew to work the 10.5cm LeFH 18 gun

It was not a movable pillbox

Some books have argued that the reason for removing the turret was because it could be used as an armoured pillbox. This was not its function. It was an artillery gun that was designed to operate behind the front line. It was not an anti-tank gun. The protective armour that surrounded the gun was not of a thickness that would have stopped armour piercing tank shells. It was only designed to protect the gun crew from small arms fire and high explosive shell and mortor round shrapnel fragments.

Two competing models

The German armament factory of Alkett and Rheinmetall-Borsig based near Berlin had come up with a similar prototype design called the 10.5 cm leFH 18/40/2 auf Geschützwagen III/IV. It did not have the lifting gear on the side of the vehicle but the turret was removable just like the Krupp-Gruson design.
It used the standard Panzer IV tank chassis and had slightly better performance than the Krupp-Gruson’s Heuschrecke IVb Grasshopper. The Alket Rheinmetall-Borsig model was completed in March 1944.

Design

In May 1943 German Army weapon designers decided to build a prototype Heuschrecke IVb. It would built using a Hummel SPG chassis and a 10.5cm LeFH 18/l light field howitzer in a removable turret.
In June 1943 the Krupp-Grusonwerk factory started work on building this new armored fighting vehicle using a new Hummel chassis number 320148. Other sources state that three prototypes were built, with serial numbers 582501, 582502 and 582503.
The Hummel self-propelled artillery gun had powerful 15cm sFH 18 L/30 heavy field howitzer mounted on a specially designed Alkett/Rheinmetall-Borsig lengthened German tank chassis called the Geschützwagen III/IV. It was also referred to as the IVb.
These prototypes were referred to as the Heuschrecke 10 or Heuschrecke IVb. The word Heuschrecke means Grasshopper. It was quite appropriate. The long folded metal lifting equipment kept on top of each track mud guard looked like a grasshoppers insect legs. The number 10 refers to the size of the gun, the 10.5cm. The number IVb refers to the modified Panzer III/IV tank chassis
Components were adopted from both the Panzer III and Panzer IV tank chassis. The more robust final drive wheels, front drive wheels and steering units plus the Zahnradfabrik SSG 77 transmission gearbox were adopted from the Panzer III Ausf.J.
The Maybach HL 120 TRM engine with its cooling system, the suspension, and idler with track tension adjustment were adopted from the Panzer IV. The engine was moved from the rear of the tank to the center of the vehicle to make room for the gun and the armored fighting compartment at the back of the SPG.
The Geschützwagen III/IV tank chassis did not have a hull mounted machine gun. Crews would be issued with a single MG34 or MG42 machine gun, carried inside the fighting compartment, for self-defence.
The Krupp-Gruson designers envisioned that the Heuschrecke IVb would start to replace the 10.5cm leFH 18 auf Gahrgestell Panzerkampfwagen II Wespe self-propelled artillery gun in May 1944.
The tank engineers at the Krupp-Grusonwerk armaments factory made changes to the superstructure and chassis to enable the Heuschrecke turret to be fitted and the installation of the hydraulic mechanism needed to dismount the turret.
The Hummel was powered by a Maybach HL 120 TRM engine that was fitted in the middle of the vehicle to allow more room for the gun crew to work the gun at the back of the vehicle. This was changed for the 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV ‘Heuschrecke IVb’ prototype. The engine and the radiators were moved to the rear of the chassis.
The Heuschrecke IVb prototype turret was armed with the 10.5cm leFH 18/1 L/28 light field howitzer. The production models, however, were to have the newer, more powerful 10.5cm leFH 43 L/28.

The 10.5cm leFH 18/6 auf Waffentrager IVb SPG under going live firing trials. Notice the slightly different configuration of the early hydraulically operated arms for dismounting the turret compared to later photographs. The gun carriage wheels have not been fixed to the rear of the vehicle for these trials. The side and rear turret panels have been folded down to give the crew more room to work the gun.

Weapon Trials

The German Army Weapons Agency (Heereswaffenamt) sent weapon testing inspectors from the Gliederung Waffenamt Prüfwesen (Wa Prüf 4) artillery section to examine the new artillery SPG. They submitted a report following their inspection visit on the 28th September 1943.
On the positive side they noted it used mature tested parts. It could be traversed through 360 degrees and fired at high elevations when dismounted. The design worked and had adequate space for stowage of equipment and ammunition. It could carry 87 10.5cm shells.
On the negative side they concluded the 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV ‘Heuschrecke IVb’ would be expensive to produce and the dismounted turret wasn’t mobile.
The first trials happened on 11th October 1943 at Hillersleben. The hydraulic arms were used to dismount the turret. It was found to be too heavy. A lighter redesigned turret was manufactured and ready for testing by the end of December 1943.
At the end of January 1943, to complement the hydraulic turret dismounting system, the design team at Krupp started work on a backup hand powered system in case of problems with the hydraulics on the battlefield.
On the 28th March 1944 the Wa Pruef 4 artillery weapon testing inspectors were present at a second demonstration of the modified 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV ‘Heuschrecke IVb’.
Their recommendations after that visit were that a hand-operated crane, for dismounting the turret, be fabricated. Wheels were to be added to the dismounted turret frame, and installing a standard gun carriage and recoil management recuperator cylinder from the le.F.H. 18 gun.
On the 31st May 1944 the newly modified 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV ‘Heuschrecke IVb’, with a parallelogram hand-operated crane and wheels for the dismounted carriage, were demonstrated to the Wa Pruef 4 artillery weapon testing inspectors.
This time their report conclusion stopped any further development and design work on this project. They concluded that the 3.8 tonne dismounted turret was unusable on the battlefield. The 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV ‘Heuschrecke IVb’ ‘Grasshopper’ never entered mass production.
There was no dramatic advantage to building this weapon over the 15cm Hummel, 10.5cm Wespe or 15cm Grille artillery self-propelled guns that were already in production. These vehicles were less complicated to produce and operate.

The 10.5cm gun

The 10.5 cm leFH 18 gun was a German light howitzer used in World War II. The abbreviation leFH stands for the German words ‘leichte FeldHaubitze’ which, translated, means light field howitzer. It was fitted with a ‘Mundungbremse’ muzzle brake to allow longer range charges to be fired and reduce the amount of recoil on the gun. This increased the operational life of the gun barrel.
The 105mm high explosive HE shell weighed 14.81 kg (32.7lb). The armour piercing shell weighed 14.25 kg (31.4lb). It had a muzzle velocity of 470 m/s (1,542 ft/s) and a maximum firing range of 10,675 m (11,675 yds). With a good gun crew, it had a rate of fire between 4-6 rounds per minute.
The 10.5cm leichte Feld Haubitze 18 gun was not very useful in the direct-fire mode against enemy armored vehicles. It could only penetrate 52 mm (2 in) of armor plate at a very short range of 500 meters.
The high explosive shell was in two pieces. It was a ‘separate loading’ or two part round. First, the projectile would be loaded and then the cartridge propellant case.

Surviving prototype

When the American Army occupied Germany at the end of the war they found a surviving 10.5cm le.F.H.18/1 L/28 auf Waffenträger IVb prototype. It was shipped back to the US Army Ordnance Corps proving grounds at Aberdeen, Maryland for testing and evaluation. It was transferred to Fort Still in 2012 and the Grasshopper 10 was restored by the Fort Sill Directorate of Logistics paint shop.

An article by Craig Moore

Gallery

10.5cm le FH18/1 (sf) auf Geschutzwagen IVB
Factory prototype 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV ‘Heuschrecke IVb’ ‘Grasshopper’ painted in Dunkelgelb dark sandy yellow livery – Illustration by David Bocquelet

10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV ‘Heuschrecke IVb’ prototype in panzer grey livery – Illustration by David Bocquelet
10.5cm le.F.H.18/1 L/28 auf Waffenträger IVb prototype.
10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV ‘Heuschrecke IVb’ ‘Grasshopper’ prototype

The two large wheels at the back of the 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV ‘Heuschrecke IVb’ ‘Grasshopper’ and the metal strut with the holes it on top of the track mud guards were used to construct a gun carriage.
Turret removal on the Grasshopper
10.5cm leFH 18/1 L/28 auf Waffenträger IVb turret
Gun crews would erect the load carrying gibbet on the back of the vehicle chassis then remove the turret. It was placed onto a the gun carriage frame on the floor. Once it was locked into position it would be raised again so the gun carriage wheels could be fitted. The gun could then be towed.
grasshoper tank carriage

Surviving Grasshopper

10.5cm le.F.H.18/1 L/28 auf Waffenträger IVb at Fort Sill, Oklahoma, USA
Restored 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV ‘Heuschrecke IVb’ ‘Grasshopper’ at US Army Fort Sill, Oklahoma, USA (Photo – Jon Bernstein)

Before it was recently restored the 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV ‘Heuschrecke IVb’ ‘Grasshopper’ was kept out in the open at the US Army Ordnance Corps proving grounds at Aberdeen, Maryland before being moved to Fort Sill.
Close up view of the 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV Heuschrecke IVb Grasshopper turret whilst it was being restored at Fort Sill. (Photo: Jon Bernstein)

The 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV Heuschrecke IVb Grasshopper under restoration in
the Fort Sill workshops. (Photo: Jon Bernstein)

Side view of the restored 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV Heuschrecke IVb Grasshopper at Fort Sill with the rear arms raised. (Photo: Jon Bernstein)

Rear view of the restored 10.5cm leFH 18/6 auf Waffenträger Geschützwagen III/IV Heuschrecke IVb Grasshopper at Fort Sill with the rear arms raised. (Photo: Jon Bernstein)

Waffenträger IVb Specifications
Dimensions (L x W x H)	6.57 m x 2.9 m x 2.65 m (21ft 7in x 9ft 6in x 8ft 3in)
Total weight, battle ready	24 tonnes (26.45 tons)
Crew	5 (commander, driver, gunner, 2x loaders)
Propulsion	Maybach HL 120TRM 12-cylinder water cooled gasoline/petrol engine, 285 hp
Fuel capacity	360 liters
Top road speed	38 km/h (24 mph)
Operational range (road)	225 km (140 miles)
Main Armament	10.5 cm leFH 18/6 howitzer with 87 rounds
Secondary Armament	Hand held 9 mm machine pistol
Hull Armor	Front 30 mm Sides and Rear 16 mm – 20 mm
Turret Armor	Front 30 mm Sides and Rear 15 mm
Total built	1 or 3

Sources

German Self-Propelled Weapons by Peter Chamberlain & H.L.Doyle
Artillerie Selbstfahrlafetten Panzer Tracts No.10 by Thomas L. Jentz
German Artillery at War 1939-45 vol.1 by Frank V.de Sisto.

Germans Tanks of ww2

German Self-Propelled Artillery Guns of the Second World War

By Craig Moore

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WW2 German SPG Prototypes

10.5 cm leFH 18/40/2 (Sf.) auf Geschützwagen III/IV

Post author By Craig Moore
Post date December 25, 2016
4 Comments on 10.5 cm leFH 18/40/2 (Sf.) auf Geschützwagen III/IV

German Reich (1942)
Self-Propelled Gun – 1 Built

Alkett’s Waffenträger Weapon Carrier

The German weapons manufacturers Alkett Rheinmetall-Borsig tried to compete with Krupp-Gruson to produce an amored fighting vehicle that would carry a 10.5cm Leichte Feldhaubitz 18/40/2 L/28 light field howitzer onto the battlefield like a self-propelled gun, and also allow the gun to be lowered to the ground.
This then enabled the tank chassis to function as an armoured ammunition carrier. The driver could return to the nearest supply point and load the vehicle with more high explosive HE shells and propulsion canisters. The gun could also be fired from its armored open top turret on top of the vehicle without the need to lower it.

Alkett prototype 10.5cm leFH 18/40/2 L/28 (Sf) auf Geschüetzwagen III/IV artillery SPG
The Krupp-Gruson design was called the 10.5cm leFH 18/1 L/28 auf Waffenträger IVb. The Alkett Rheinmetall-Borsig design was given the name 10.5cm leFH 18/40/2 L/28 (Sf) auf Geschüetzwagen III/IV. The German word Waffenträger means ‘weapon carrier’ and Geschüetzwagen translates to ‘gun vehicle’ (it was often abbreviated to just GW). Both words are appropriate to describe these vehicle’s function.
It was also called the 10.5cm leFh/40/2 (Sf) Geschutzwagen PzIVb, or 10.5cm leFh/40/2 (Sf) GW PzIVb or 10.5cm le.F.H. 18/40/2 L/28 (Sf) auf GW III/IV. The letters (SF) stand for ‘Selbstfahrlafette’ – self-propelled carriage. The abbreviation leFH stands for the German words ‘leichte FeldHaubitze’ which, translated, means light field howitzer.
To remove the turret and gun on the Krupp-Gruson design, a large folding metal gantry was mounted on the rear of the vehicle. When it was folded down the long metal arms were stowed on top of the track guards. This vehicle was given the nickname of the Heuschrecke, the Grasshopper, as the folded metal arms looked like the legs of a grasshopper.
It is easy to tell the two designs apart. The Alkett Rheinmetall-Borsig 10.5cm weapon carrier does not have any external folding metal struts on top of its track guards unlike the Krupp-Gruson design.
The 10.5cm LeFH 18/40/2 L/28 light field howitzer’s carriage rails and wheels were stowed at the rear of the vehicle on the outside. When the gun crew wanted to dismount the howitzer from the vehicle to use it as conventional artillery gun on the ground, they would unlock the gun from its mount and use a jack to lift it up and off.
The armored superstructure of the turret is hinged at the front to allow it to be folded forward to give more room to the gun crew during the removal procedure. The carriage, carriage wheels, and rear rails would then be reattached. A ramp down from the top of the vehicle would be fitted and a manual block and tackle winch system were used to lower the gun down to the ground. The reverse procedure would be used to remount the gun on top of the vehicle.
The howitzer could be fired from on top of the vehicle like a normal self-propelled gun. It could traverse through 360 degrees, as it was mounted on a turntable gun platform that was counter sunk into the top of the tank chassis.
There was no top to the turret. There were a few disadvantages of an open topped vehicle. The crew was exposed to the elements and were also at risk of injury from enemy thrown hand grenades, mortars and shrapnel from air burst enemy shells. A canvas tarpaulin rain cover was produced to give some protection from the elements.

10.5cm leFH 18/40/2 L/28 (Sf) auf GW III/IV artillery SPG

Design and testing

Alkett submitted its designs for a 10.5cm howitzer weapons carrier self-propelled gun to the German Army Weapons Agency (Heereswaffenamt) Gliederung Waffenamt Prüfwesen (Wa Prüf 4) artillery section on 27th September 1943.
The first prototype was ready for testing on 28th March 1944. It was demonstrated to the Wa Pruef 4 weapons inspectors at Hiliersleben. The gun crew took around 15 minutes to dismount the howitzer and mount it on the newly designed Schiesspilz (firing pedestal). The gun could not be traversed a full 360 degrees on the ground.
The inspectors submitted a report that recommended the protective turret armor was to be increased in thickness, that the Schiesspilz (firing pedestal) be carried on the vehicle, and that the howitzer be modified so that it could fire to the rear of the vehicle at an angle of -5 degrees.
Alkett suggested that the turret superstructure armor could be angled to increase the gun crew’s protection. This suggestion was rejected as it decreased the amount of ammunition that could be stored.
The Wa Pruef 4 weapons inspectors re-evaluated the new modified prototype after a second demonstration on 28th May 1944. They were happy with the changes. As a Panzer III/IV self-propelled gun tank chassis was going to be used, it was felt that field trials would not be necessary as this chassis was already being used in the production of the Hummel and Nashorn self-propelled guns.
The design team at Alkett/Rheinmetall-Borsig had already lengthened a German tank chassis. It was called the Geschützwagen III/IV. Components were adopted from both the Panzer III and Panzer IV tank chassis. The more robust final drive wheels, front drive wheels and steering units plus the Zahnradfabrik SSG 77 transmission gearbox were adopted from the Panzer III Ausf.J. The Maybach HL 120 TRM engine with its cooling system, the suspension, and idler with track tension adjustment were adopted from the Panzer IV.
The first twenty-five production 10.5cm leFH 18/40/2 L/28 (Sf) auf Geschuetzwagen III/IV were due to be completed by October 1944 but there were long delays at the factory. The German Army Weapons Agency (Heereswaffenamt) canceled the order on the 12th December 1944 before any were completed.
A revised design which did not feature the countersunk turntable gun platform was put forward and accepted. The gun would now only have a limited traverse when mounted on the tank chassis like a normal self-propelled gun. This was hoped to make production cheaper and simpler. An initial order for 250 of these vehicles was approved. The first 35 would be built by February 1945 and the rest to follow. There are no production report documents that suggest any of these vehicles were produced.
There was no dramatic advantage to building this weapon over the 15cm Hummel, 10.5cm Wespe or 15cm Grille artillery self-propelled guns that were already in production. These vehicles were less complicated to produce and operate.

The 10.5cm gun

The 10.5 cm leFH 18 gun was a German light howitzer used in World War II. The abbreviation leFH stands for the German words ‘leichte FeldHaubitze’ which, translated, means light field howitzer. It was fitted with a ‘Mundungbremse’ muzzle brake to allow longer range charges to be fired and reduce the amount of recoil on the gun. This increased the operational life of the gun barrel.
The 105mm high explosive HE shell weighed 14.81 kg (32.7lb). The armor piercing shell weighed 14.25 kg (31.4lb). It had a muzzle velocity of 470 m/s (1,542 ft/s) and a maximum firing range of 10,675 m (11,675 yds). With a good gun crew, it had a rate of fire between 4-6 rounds per minute.
The 10.5cm leichte Feld Haubitze 18 gun was not very useful in the direct-fire mode against enemy armored vehicles. It could only penetrate 52 mm (2 in) of armor plate at a very short range of 500 meters.
The high explosive shell was in two pieces. It was a ‘separate loading’ or two part round. First, the projectile would be loaded and then the cartridge propellant case.

An article by Craig Moore

Sources

German Self-Propelled Weapons by Peter Chamberlain & H.L.Doyle
Artillerie Selbstfahrlafetten Panzer Tracts No.10 by Thomas L. Jentz
German Artillery at War 1939-45 vol.1 by Frank V.de Sisto.

The 10.5cm leFH 18/40/2 L/28 (Sf) auf Geschuetzwagen III/IV prototype painted in Dunkelgelb. Illustration made by Jarja.

The same vehicle illustrated by David Bocquelet

Gallery

10.5cm Leichte Feldhaubitz 18/40/2 L/28 (Sf) auf Geschüetzwagen III/IV prototype artillery weapon carrier self propelled gun.

Gun carriage wheels attached to the rear of the 10.5cm LeFH 18/40/2 L/28 (Sf) auf Geschüetzwagen III/IV prototype artillery SPG
Alkett prototype 10.5cm leFH 18/40/2 L/28 (Sf) auf Geschüetzwagen III/IV artillery SPG
A 10.5cm LeFH 18/40/2 L/28 (Sf) auf Geschüetzwagen III/IV in the middle next to a Nashorn SPG.

Surviving vehicle

Surviving 10.5cm leFH 18/40/2 L/28 (Sf) auf Geschüetzwagen III/IV prototype owned by Kevin Wheatcroft and kept in storage in Southern England.

Along the top of the open casement superstructure are small D rings. These were used to tie down the bad weather tarpaulin.

Notice the empty retractable Gun carriage wheel holders at the back of this preserved 10.5cm leFH 18/40/2 L/28 (Sf) auf GW III/IV.

Specifications
Dimensions (L-W-H)	7.19 m x 3 m x 2.87 m (23ft 6in x 9ft 8in x 9ft 4in)
Total weight, battle ready	25 tonnes (27.55 tons)
Crew	5 (commander, driver, gunner, 2x loaders)
Propulsion	Maybach HL 120 TRM 12-cylinder water cooled gasoline/petrol engine, 265 hp
Fuel capacity	500 liters
Top road speed	42 km/h (26 mph)
Operational range (road)	300 km (186 miles)
Main Armament	10.5 cm leFH 18/40/2 L/28 howitzer with 85 rounds
Secondary Armament	Hand held 9 mm machine pistol
Hull Armor	Front 30 mm Sides and Rear 20 mm
Turret Armor	Front 10 mm Sides and Rear 10 mm
Total built	1

Germans Tanks of ww2

German Self-Propelled Artillery Guns of the Second World War

German Reich (1943) Self-Propelled Gun Battery – None Built

Details: Not Many

User: Navy Maybe?

Projekt NM Specifications

Sources

German Reich (1942) Self-Propelled Gun – 1 Built

The Tiger gun carrier

Design and Problems

Armament

Crew members

Mobility

A Troubled End

Gallery

Wrong photos

Grille 17/21 specifications

Sources

German Reich (1942-1944) Self-Propelled Superheavy Siege Guns – None Built

“It seemed like a good idea at the time”

Tiger H als Tragfahrzeug für schwerste Geschütze

Gerät 566 Lastenträger 606/5 für K 5/3 (Tiger)

28 cm DKM 44 auf Panther Langholzprinzip

Epilogue

Sources

German Reich (1942-1945) Self-Propelled Guns / Weapon Carriers – Several Wooden Mockups Built

Animal Farm

Krupp’s Cricket – (Sfl.) Krupp I and II

If at First You Don’t Succeed… – Selbstfahrlafette mit Absetzbarer 15 cm sFH 18

Skorpion of the Rhein – (Sfl.) Rheinmetall-Borsig

Not Done Yet – 15 cm sFH 18 auf Panther Bauteilen

Round Two – Mittelerer Waffenträger sFH 18 auf Panther

Never Give Up, Never Surrender

Sources

German Reich (1943-1944) Self-Propelled Gun – 4 Prototypes Built

Weapon Carrier or SPG?

The Raupenschlepper Ost RSO tracked vehicle

7.5 cm Gebirgshaubitze 36 auf Raupenschlepper Ost (RSO/3)

7.5 cm GebH 36 auf Gebirgsraupenschlepper (RSG)

10.5 cm Gebirgshaubitze 40 auf Raupenschlepper Ost (RSO/1)

15 cm sIG 33 auf Raupenschlepper Ost (RSO/3)

Conclusion

Specifications

Sources

German Reich (1942) Self-Propelled Gun – 1 or 3 Built

The Grasshopper

It was not a movable pillbox

Two competing models

Design

Weapon Trials

The 10.5cm gun

Surviving prototype

Gallery

Surviving Grasshopper

Waffenträger IVb Specifications

Sources

German Reich (1942) Self-Propelled Gun – 1 Built

Alkett’s Waffenträger Weapon Carrier

Design and testing

The 10.5cm gun

Sources

Gallery

Surviving vehicle

Specifications

German Reich (1943)
Self-Propelled Gun Battery – None Built

German Reich (1942)
Self-Propelled Gun – 1 Built

German Reich (1942-1944)
Self-Propelled Superheavy Siege Guns – None Built

German Reich (1942-1945)
Self-Propelled Guns / Weapon Carriers – Several Wooden Mockups Built

German Reich (1943-1944)
Self-Propelled Gun – 4 Prototypes Built

German Reich (1942)
Self-Propelled Gun – 1 or 3 Built

German Reich (1942)
Self-Propelled Gun – 1 Built