ARL 37 ‘Char de Rupture’ | Three shots, three misses


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From Soldier to Student: A Guide to Higher Education for Veterans

This guest post has been offered free of charge by the Tank Encyclopedia team for

Transitioning into civilian life can require veterans to make some serious choices. One of the most common decisions that vets face while preparing for this transition is whether to go back to school. Whether it’s to earn a basic degree or a more advanced certification, if you are facing a similar choice, having these tips can help you navigate the process and achieve your educational goals.

Choosing Your Degree

If you’re like most veterans, you’re likely going back to school in order to boost your post-service career prospects. Earning a degree can not only put you in the running for more jobs but could also potentially earn you a bigger paycheck. Here are some options to consider:

Computer Science

Take a look at the top career fields across the country and you will see that tech jobs dominate the list. Whether you want to be an internet security specialist or web developer, having a degree in computer science can give you an edge over the competition. Best of all, you can complete your educational goals online by earning your computer science degree from WGU.


Want to work in sales or finance? Then you may want to think about going back to school to earn a business degree. Depending on what sort of courses you complete, you could put yourself in the running for some pretty lucrative positions. Having all of that business savvy can also come in handy if you are dreaming of opening your own business at some point. So, you could even consider taking things one step further and getting an MBA.

Health Sciences

If you signed up for active duty because you wanted to help other people, a career in healthcare could be your perfect fit after that service has ended. Aside from always being in demand, healthcare workers also tend to enjoy competitive salaries and flexible work schedules. There are also careers to fit just about any set of work and education experience imaginable. In fact, you don’t need an advanced degree to earn an impressive paycheck in healthcare.

Covering Your Expenses

Now let’s get down to brass tacks and talk about how to pay for the degrees and training mentioned above. If you’re a veteran, you’re actually in luck because there are several financial programs that can make going back to school more affordable, including:

Veterans Benefits

If you want to earn your degree without paying a single cent, you should start by signing up for the benefits you are owed for your military service. For example, qualifying veterans could have up to 100 percent of their tuition and fees covered but they may also be eligible to receive allowances for housing, books, and other educational expenses.


Need more help with your educational expenses? Or, perhaps you want to help your spouse go to college as well? Then you can also consider applying for one of several scholarship programs aimed at supporting veterans and dependent family members in their educational pursuits. These scholarships are offered by a variety of corporations, non-profit organizations, and professional associations, but the amount of each award can vary. Read through all of the application materials to see award amounts and specific requirements.

Grants and Loans

Before you sign up for your first class, you may also want to fill out a FAFSA form online. The Free Application for Student Aid will give you access to federal grant and loan programs that can also help to offset educational expenses. Even if you qualify for the GI Bill and other scholarships, completing a FAFSA may be worthwhile since you can use federal funds in conjunction with existing educational benefits.

With so many degree choices and financial options, there’s no reason why going back to school can’t fit into your own military transition. There may be challenges along the way, but you’re used to overcoming some pretty tough situations as an active duty military member. Take those lessons and skills and combine them with these tips to forge your own path forward.

When you want to learn more about tanks in-between classes, be sure to check out specs, resources, and information on the Tank Encyclopedia.

Photo Credit: Benjamin [email protected]


Hungarian WW2 Armor


(P) Military History and Influencers

The Military History field has seen an enormous boom in popularity in the last 20 years, especially helped by the rise of the internet and two of its applications: blogs and Youtube.

However, one of the best aspects of this growth is not so much the growth of quantity, but the growth in quality! While there are more low-quality poor information website and Youtube channels available than ever, there are also a lot of very high quality highly reputable ones coming up as well. And if their existence is not enough, they also do tend to be quite popular! Youtube channels such as The Chieftain, Kings and Generals, Forgotten Weapons and Military History Visualized, and hundreds of quality history blogs garner hundreds of thousands of views while being historically accurate and doing in-depth analysis of a lot of aspects of history and technology that have just been ignored up to now.

The rise of Youtube and the appearance of a number of highly-popular historically-based games have also given rise to a large number of gamer Youtube channels focusing on this niche of the market.

Marketing agencies call such channels, websites and persons ‘influencers’, due to their large popularity and ability to influence their respective audiences, making them attractive targets for focused marketing campaigns.

Such channels and websites used to be supported by ad revenue from Google and Youtube Ads. However, not only has revenue from such sources shrunk significantly in the last years but Google, Youtube, and Facebook have turned more and more against history channels, demonetizing them or limiting their organic growth.

This has left open only two options for such creators, crowdfunding (which has picked up tremendously in the last years and have allowed the average person to become a patron of history) and influencer marketing. The latter basically consists of a partnership between the creator and a brand for advertising. The Chieftain and Wargaming, various tank Youtubers and War Thunder, everybody else and Raid: Shadow Legends are just a couple of examples of such collaborations.

Of course, ideally, every creator would like to work with brands that are close to his topic, but that is not always possible, as unfortunately, except for the large video games, the military history sector is economically rather weak. Casinos, academic writing websites, and many others will try to tempt creators into publishing unmarked guest posts, but that is often hurtful both to the creator and to the readers.

Fortunately, websites such as Intellifluence exist, which allow brands to make contact with influencers and prepare campaigns in a manner that benefits both of them. For example, our research work involves a lot of working with military history books, and we would love to do guest posts for book publishers and authors! Intellifluence even has an easy tutorial for such brands to set-up marketing campaigns for their books!

This guest post has been sponsored by Intellifluence.

WW2 German prototypes


ww2 German half-tracks Nazi Germany (1935-39)
Heavy Tank – 3 Hulls & 1 Turret Built

The Tiger I and the Tiger II are some of the most famous tanks in the whole history of armored warfare. These behemoths of World War Two have captured the imagination and attention of many generations of tank lovers and armor researchers. However, while the Tiger was the product of a rushed development following the lessons of Operation Barbarossa, the German quest for a heavy breakthrough tank stretches back to 1935, with the design process of a 30 ton Panzer that would become the Durchbruchswagen.

A Long Incubation

The first mention of what would eventually become the Tiger series appears in a report from October 1935, at a time when Germany had barely started building the Panzer I. General Liese, the head of the Heeres Waffenamt, the German Army Weapons Agency, stated that:

“The initial velocity of the 7.5 cm gun must be increased to about 650 meters/second to be effective against the Char 2 C, 3 C, and D. This type of increase requires the design of a completely new Panzer. Based on rough calculations, armor protection up to 20 mm thick (still not fully protected against 2 cm guns) would result in a weight of at least 30 tonnes. The head of the army recently spoke out against this type of tank. As a follow-up action, confirm that the development of a medium Panzer weighing about 30 tonnes with a 7.5 cm gun with increased capability can be dropped.”

It is notable that a 30 tonne tank was seen as a medium tank at the time, given that the newly built Panzer I weighed just 5 tonnes, while the first versions of the Panzer IV would go on to weigh 18 tonnes. Nonetheless, it is important to note that this tank, armed with a 7.5 cm gun, was intended as a counter to enemy heavy tanks, most notably the French Char 2C and the Char 2C bis, incorrectly called the 3C in the document.

The weight of 30 tonnes was chosen because, as was brought up during a 1936 meeting on the development of an engine for this tank:

“a higher weight would hardly be allowable when considering the Pionier bridging equipment”

The 30 tonne Panzer development project was not dropped by the Army and reappeared in the documentation in December 1935, with the problem of the engine:

“Dipl.Ing. Augustin turned the discussion to the development of a 600 hp engine for the heavy Panzers and noted that his opinion was that 600 horsepower will not be sufficient and that indeed it would be more correct to immediately develop a motor capable of 700 hp.”

This was just wishful thinking. At this point, Maybach was barely testing a 300 hp engine. The planned 600 hp 32 liter Maybach HL 320 V-12 petrol engine never got built. One year later, in October 1936, Wa Pruef 6, the German design office for armored vehicles, sent a request to Krupp for a conceptual design of a turret for this 30 tonne Panzer sporting the 7.5 cm L/24 gun.

Reproduction of the Durchbruchswagen experimental hull based on the description given by Dipl.Ing. Adders, the head of the design department of Henschel, following his interrogation by British Intelligence in 1945. Note that the five road wheels on each side are offset from each other indicating the use of torsion bar suspension. Source: Germany’s Tiger Tanks, D.W. to Tiger I

A Tank With Many Names

At this point, the 30 tonne Panzer was known as the Begleitwagen (verstaerkt), meaning ‘Escort Vehicle, Strengthened’. This indicates that the new 30 tonne Panzer was meant to cover the same role as the Panzer IV, which was also known as the Begleitwagen in its development. This would have meant that small units of 30 tonne Panzers would have been used to accompany lighter tanks during operations, being responsible for taking out enemy strongpoints which could be destroyed using their high explosive shells.

In March 1937, this designation was changed into Infanteriwagen, or ‘Infantry vehicle’. This also indicates a change in the role it was meant to carry out, presumably to having to work alongside friendly infantry to overcome enemy defenses, probably closer to the British and French concepts of an Infantry tank. This would not last long and, in April 1937, the vehicle would receive its most known designation, Durchbruchswagen, or ‘Breakthrough vehicle’. Again, this probably came with a role change, a role that would stick with the German heavy tanks up to the E100. This breakthrough role, which also appears in both Soviet and French armored doctrines before the war, proposed the use of heavy tank units to punch through the enemy defensive line, thus creating a breach which could then be exploited by other armored and motorized divisions.


The construction of the first Durchbruchswagen began with a January 1937 order from Wa Pruef 6 to the Henschel company for the design of a chassis for the 30 tonne Panzer. This would cement a practice that would hold on for most of the German heavy tank development of having two companies designing the vehicle, Krupp doing the turret and gun and another company doing the chassis. Two versions were built, the D.W.1 and the D.W.2, meant to be delivered in the second half of 1938, mostly with automotive differences.

Drawing of the Durchbruchswagen 1 by H.L.Doyle showing the vehicle with a test weight instead of a turret. Source: Tiger and its Variants

Durchbruchswagen I

The Durchbruchswagen I was protected by flat 5 cm thick armor on the front, sides and rear, which was meant to be proof against the armor-piercing shells of the German 3.7 cm PaK, although it is unclear at which range this was supposed to be at. The Armor Piercing (A.P.) shell of the 3.7 cm could penetrate more than 5 cm of armor at point blank range. To give a comparison, the Panzer IV Ausf.F, which had the same gun, same engine, a very similar turret and the same 5 cm frontal armor, weighed just over 7 tonnes less than the Durchbruchswagen’s intended weight. A significant part of this difference can be accounted for by the thinner side, rear, top and bottom armor, although other differences between the two tanks make this comparison just indicative.

The roof and bottom of the hull were 2 cm thick. The armor at the front was stepped. However, both of the constructed vehicles were made out of ‘soft’ (not armor) steel, as they were meant mostly for automotive tests. Also, due to the inability of existing milling machines to fabricate such long 5 cm armored plates, the side armor was made from two parts, with a split at the front of the engine compartment. At the joining, they were riveted to an internal frame. This increased the weight of the vehicle and affected the structural integrity of the side armor.

For that time, this was quite thick armor. Only the Char B1 bis had thicker armor (60 mm front and 55 mm sides), with the SOMUA S35 also having similar armor (47 mm front, 40 mm sides). Furthermore, just like on the Tiger I prototype, there was a foldable armor plate that could be lowered using hand cranks to protect the drive sprockets at the front. This foldable armor plate was allegedly put through a protection test which it failed. There were two escape hatches in the bottom of the tank, one on the right front, close to the radio operator, and one at the rear left of the hull, in the engine compartment. This could be accessed through a door in the firewall that separated the engine from the crew compartment. While not specifically mentioned in any source, the Durchbruchswagen I hull probably had a driver’s visor in the front of the upper glacis and a hatch in the roof. The radio operator on the right side of the front hull also probably had a hatch in the roof and a ball-mount machine gun.

The engine was a 12-liter water-cooled gasoline Maybach HL 120 TR giving out 280 hp, placed at the rear of the tank. The TRM version of this engine also propelled the Panzer III, Panzer IV and their derivatives. The engine was coupled to a Maybach-Motorenwerk Variorex semi-automatic transmission, also used on the Panzer III, placed at the front of the tank. These could allegedly propel the vehicle to a maximum speed of 35 km/h. The steering system consisted of three Cletrac stages in series. A Cletrac system allows the transfer of power from one track to the other when steering, without the usual loss of power due to braking. The three stages allowed the use of three different turning radiuses, so the tank could make a shallower or tighter turn without losing power. However, problems appeared with the steering system, with the cast iron housing being broken twice. The exhaust was at the rear of the tank, coming down from the upper part of the rear of the vehicle. There were also problems with the brakes, as the first version, done by Henschel, gave out a lot of smoke when breaking, so the coating had to be replaced.

One of the only two known images of the D.W. tanks, showing the final drives, first roadwheel and first shock absorber of the D.W.2. Source: Tiger and its Variants

The running gear consisted of a drive sprocket at the front, an idler at the rear, three return rollers and five medium-size double road wheels on each side. They had rubber rims in order to decrease the noise made by the tracks. Due to the use of a torsion bar suspension, the road wheels were not symmetrically placed. The ones on the right side of the tank were slightly forward compared to the ones on the left. The torsion bars were square and hollow on the inside. They were very soft-springed, meaning that they could give a smoother ride in certain conditions, but could not handle rough terrain and would lead to a lot of pitching during driving and when stopping or starting. Two shock absorbers were mounted on each side, one on the first roadwheel and one on the last roadwheel. These were meant to assist these torsion bars, as they were subjected to stronger shocks, especially when stopping or accelerating. Also, bump stops were added to the suspension in order to stop the road wheels from being deviated too much and thus protecting the tank from bellying out. The tracks had a pitch of 300 mm. The pitch of a track is the distance between the centers of two subsequent track links. In general, decreasing the pitch could lead to better speed and ride, but also means more track links were needed, with more connections and more parts. The tracks were lubricated and could be fitted with rubber pads. The rubber pads would have made the tank quieter and less prone to damaging or destroying the pavement on roads, while the lubrication decreased friction and thus increased the speed of the vehicle. These were both characteristics that seem to have been carried over from half-track designs.

The crew probably consisted of five people as on other German tanks being developed at that time. This would have included the driver and radio operator in the front part of the hull of the tank, and a gunner, a loader and a commander in the turret. This would have been a very important feature of this vehicle, as it would have allowed the commander to focus on his duties of observation and tactical leadership instead of having to aim and load the gun.

The dimensions of the Durchbruchswagen are not available in any of the sources, but it can be reasonably assumed that they would have been similar to those of the VK30.01(H). This later vehicle had a length of 5.7 and a height of 2.6 meters. The width of the VK30.01(H), of 3.1 meters, was probably larger than that of the D.W. due to the different suspension system. Nonetheless, these values are also very close to those of the Panzer IV.

Drawing of the Durchbruchswagen 2 by H.L.Doyle, showing a Panzer IV-like turret. The main outside differences compared to the D.W.1 drawing are the one-piece side armor, the crew escape hatch in the lower side and the different side viewport for the driver. It is unclear if these differences are historical or just speculative. Source: Tiger and its Variants

Durchbruchswagen 2

Work on the Durchbruchswagen 2 was started halfway through 1937 and it mostly had automotive improvements. In the book ‘Tiger and its variants’, Doyle’s drawing of the D.W.2 shows it with the one-piece side armor. However, in the book ‘Germany’s Tiger tanks’, Jentz specifically mentions that the one-piece side armor was introduced with the VK30.01(H) neue Konstruktion, and thus the D.W.2 should have the two piece side armor. Similarly, ‘Tiger and its variants’ shows the addition of a hull side-escape hatch to the D.W.2 while ‘Germany’s Tiger tanks’ makes no mention of such a thing.

Automotive-wise, the larger stages of the previous Cletrac system were replaced with a three-stage differential with magnetic clutches. Not only did these allow for power to be transferred from one track to the other while turning, but a triple stage differential also allowed to reverse one track with respect to the other, thus allowing the tank to neutral steer. The Cletrac stage with the smallest turning radius was kept though.

Also, the track pitch was decreased to 260 mm, which is claimed to have significantly improved the ride of the vehicle. The torsion bars were also changed to a more rigid type, with a three-times larger springing constant.

Due to these changes, the drive sprocket, final drives and parking brakes also needed to be modified.

The shorter pitch tracks of the Durchbruchswagen 2. This is one of only two known photos of the D.W. tanks. Source: Tiger and its Variants

The Turret

These two hulls were supposedly trialed to test all the components and identify what improvements could be made for future projects. However, almost no details remain about these tests. What is certain is that the Durchbruchswagen was not accepted as built.

Work on the Durchbruchswagen turret was done in parallel to that on the hulls. Krupp sent the requested conceptual drawings for the turret in February 1937, and was quickly informed by Wa Pruef 6 to use it as a basis for subsequent development. In the March 1937 answer, Wa Pruef details the desired characteristics of the D.W. turret.

The turret was to have a turret ring diameter of 1,500 mm, smaller than that of the Panzer IV. Also, the turret would be rotated manually, as

“No plans are made for an electric drive for traversing the turret. Auxiliary traversing gear for the loader is to be included.”

The armor of the turret would be 50 mm all around, with a 20 mm external mantlet and a 15 mm turret roof, affording similar protection as the hull. There is no other information on the shape of the turret of the Durchbruchswagen, although H.L.Doyle’s line-drawing in ‘Tiger and its variants’ shows a Panzer IV-like turret with a large commander cupola at the rear, a crew access hatch and a vision port on each side.

The gun to be used in this turret was the same 7.5 cm Kampfwagenkanone L/24 that would be mounted on the early versions of the Panzer IV. In a meeting in January 1939 on the topic of the heavy 30 tonne Panzers, it was expressly specified that no gun larger than the short 7.5 cm should be pursued because the increased weight would have to be compensated by a decrease in armor, which was deemed unacceptable.

The main shell for this gun was the Sprenggranate 34 high-explosive shell. This shell weighed around 4.5 kg and had an explosive filler of almost half a kilogram. This was meant to be used against enemy infantry, machine-gun posts, anti-tank guns, bunkers and soft-skinned vehicles. For anti-tank purposes, a series of High Explosive Anti Tank (H.E.A.T) shells were introduced during the lifetime of this gun, with penetrations ranging from around 45 mm to over 100 mm, although they were introduced into service later. Two types of Armor Piercing Capped Ballistic Capped (A.P.C.B.C.) shells were also available, with a penetration of 54 mm to 60 mm at 100 m distance. An APCBC shell works basically as a normal Armor Piercing (A.P.) shell, but has two additional caps added to the tip of the shell. The first cap is made of soft metal and is meant to absorb a part of the shock on impacting the armor and thus preventing the armor piercing tip from shattering. The ballistic cap was a hollow light cone added on the top of the shell with the sole purpose of improving the aerodynamics of the shell. This improved both accuracy and the penetrating power, as the shell kept more of its kinetic energy at longer ranges.

Another machine gun (most probably an MG 34) would have probably been mounted coaxially with the gun. The instruction letter from March 1937 specifies that the radio should be mounted in the turret, behind the gun. However, this seems impossible to do in a Panzer IV-like turret. If the turret was as the one drawn by Doyle, then the radio would have almost certainly been mounted in the hull.

Krupp finished the D.W. turret in May 1939, building it from soft steel. It was then shipped to Magdeburg, where it was put on display along with other developments, such as the Panzer IV turret. Nothing is known about what happened after this with the turret.

The End of the Line

The Durchbruchswagen project melts into the subsequent VK 30.01 (H), which inherited many of the characteristics of the D.W. designs. The Durchbruchswagen design also underwent its last designation evolution in November 1939, also receiving the designation Vollketten 30.01 (H) alte Konstruktion.

Nonetheless, a final D.W. hull was constructed from armor plate for ballistic tests. This hull had some changes compared to the previous two hulls, having slightly different armor values that were closer to those on the VK30.01(H). This was completed after September 1940 and shipped to Kummersdorf for firing tests. No information about the results are currently available.

The armor scheme of the single D.W. hull constructed from armor plate. However, these thicknesses were changed to be closer to those intended for the VK30.01(H). Source: Germany’s Tiger Tanks, D.W. to Tiger I

A Note on Sources

There is almost no photographic evidence for the Durchbruchswagen. The only known photographs of the project were published in ‘Tiger and its variants’ and consist of a photograph of the tracks and one of the final drives at the front of the vehicle, along with a roadwheel and a shock absorber. This paucity of photographic evidence is disturbing. Other visual references include a 1940 armor scheme of the ballistic test hull and a 1945 British reconstruction of the D.W. hull based on the interrogation of Dr. Aders, the head of the design department of Henschel. Finally, two beautiful line drawings from Hillary Louis Doyle are available in the book ‘Tiger and its variants’, but how many of the details on it are based on historical references and how many are conjectural is unknown.

It is also important to note that there is annoyingly little information available on the Durchbruchswagen, with only three books treating it in any detail. Even so, most of the technical details and specifications come from the 1945 interrogation of Dr. Aders by the British and not from contemporary German documents, so they should be treated with a degree of skepticism.

Dipl. Ing. Erwin Aders, one of the main designers involved in the Durchbruchswagen project. Source: Tiger and its Variants


Nowadays, the Durchbruchswagen are mostly forgotten except for some mentions in a couple of books and their appearance in a popular video game. However, they played an important role in the development of German heavy tanks that would culminate in the Tiger tanks. They were the main designs worked on at a time when the German heavy tank doctrine was being crystallized. Also, they were very important in testing the capabilities of the German armaments industry and helping identify where research and development were needed, such as designing better armor milling, better suspension and better engines.

Nevertheless, the Germans would not adopt a heavy tank for the Wehrmacht until 1942, meaning that the German tank divisions went into the Second World War without such a vehicle. During the peak of the German offensive successes, when such a tank would have been most useful in breaking down Polish, French, or Soviet defensive lines, none was available. The Germans nonetheless achieved great success despite the thin armor of their tanks due to excellent communications, training, leadership, and tactics.

Illustration of the Durchbruchswagen 2 based on H.L.Doyle’s drawing produced by Tank Encyclopedia’s own David Bocquelet. The hull side is in one piece


Dimensions Around 5.7 x 3.1 x 2.7 m
Armament 7.5 cm Kampfwagenkanone L/24
Machine Guns 2 x MG 34
Armor 50 mm hull front, rear and sides
20 mm hull roof and floor
50 mm turret front, rear and sides
15 mm turret roof
Weight Around 30 tonnes
Crew Probably 5 (driver, co-driver, commander, gunner, loader)
Propulsion Maybach HL 120 TR, 280 hp
Max Speed Allegedly 35 km/h
Total Operated 3 hulls and 1 turret built


Panzer Tracts No.6 Schwere Panzerkampfwagen D.W. to E100 including the Tigers, T.Jentz and H.L.Doyle
Germany’s Tiger Tanks, D.W. to Tiger I, Design, Production and Modifications, T.Jentz and H.L.Doyle
The Tiger tank and its Variants, W.Spielberger and H.L.Doyle


M1A2 Abrams from Trumpeter in 1/35 – TE Modelling Video #12


(P) Exploring Arizona’s Military History – Arizona Commemorative Air Force Museum

Click to visit the website of the Arizona Commemorative Air Force Museum!

Arizona has a rich military history, making it an ideal destination for history buffs, particularly those interested in the Army and the Air Force. Especially since World War II, the state of Arizona has served as a key training and testing ground, and residents of the state has served with honor. For those interested in learning more about Arizona’s contributions to America’s military greatness, these 3 sites offer exciting insights and opportunities to interact with important artifacts from past campaigns.

Airbase Arizona Museum

For the United States, World War II got its start when the Japanese bombed Pearl Harbor, sinking the USS Arizona in December 1941, and today a remnant of this ship can be seen at the Airbase Arizona Museum in Mesa, Arizona. Long kept in a US Navy storage yard, this remnant was just moved to the Mesa museum in June 2019, the USS Arizona joins a significant collection of warplanes, including a B-17 Flying Fortress and B-25 Mitchell. With exhibits documenting 100 years of military aviation history, you shouldn’t miss this exciting museum.

Arizona Military Museum

Phoenix is one of the United States’ most vital and quickly growing metro areas, with Midtown Phoenix playing host to mixed-use developments, museums, and the Phoenix VA Healthcare System, which is one of the area’s largest employers – and the importance of the VA in this city should come as no surprise. Phoenix is home to a large population of military veterans, as well as the Arizona Military Museum.
Part of the Papago Park Military Reservation, the Arizona Military Museum is dedicated to the state’s veterans, tracing all the way back to the time of the conquistadors. More recently, the Arizona Military Museum has added exhibits highlighting the War on Terror, providing visitors with a complete look at how Arizonans have fought to protect the United States for centuries.
Arizona Mesa commemorative Air Force Museum Nieuport 28
A WWI French-built Nieuport 28 biplane fighter aircraft at the Airbase Arizona Museum – Source: Marine 69-71 on Wikipedia Commons.

A superb photo of a North American B-25 Mitchell at the Airbase Arizona Museum – Source:

Arizona/California Maneuver Area

One reason that Arizona has played such an important role in American military history is that the large amount of unpopulated desert space makes for an ideal training ground. Leading up to their deployment during World War II, then, a large stretch of desert between Arizona and California was home to Canal Defence Light (CDL) Tank training, which was a secret project of
the American military. British soldiers also visited the area to train in their M3 CDLs, before being dispatched to Egypt.
For those who want to visit the Arizona/California Maneuver Area, there isn’t exactly a singular site, though there are a number of official camps you might choose from, including Camp Bouse, where the British trained. Rather, the area is broadly bounded by Palm Springs, California in the west, Yuma, Arizona in the south, Prescott, Arizona to the east, and Searchlight, Nevada in the north. Much of this area has also undergone substantial development and urbanization since that time, but some of the camps and forts in the region can provide insight into the area’s importance.
Arizona continues to cultivate memorials to its military history, including the new Fort Tuthill Military Museum, as well as through regular public events. What all these sites have in common, though, is a great reverence for our veterans and the ways in which Arizona has helped sustain our military and to drive support for the decades to come.

An American McDonnell Douglas F-4 Phantom II jet interceptor at the Airbase Arizona Museum – Source: Marine 69-71 on Wikipedia Commons

Hello, dear reader! This is a sponsored post for the Arizona Commemorative Air Force Museum. We will never accept paid posts that are malicious or are not of interest to you. All the funds from this sponsored post will be added to the Tank Encyclopedia War Chest and used for illustrations.
WW1 British prototypes

Lincoln No. 1 Machine

UK United Kingdom (1915)
Prototype – 1 built

The First World War was supposed to end quickly. Most of the high-ranking officials of the participating countries expected and planned for a short war, in which they would quickly crush their enemies and win glory and territories for their nations. However, after the German defeat at the First Battle of the Marne (6-12th September 1914), the Germans started digging in behind the River Aisne. The war was just one month old.
By March 1915, the trench lines on the Western Front spanned from the English Channel to the Swiss frontier. Bogged down in soft mud caused by heavy artillery bombing and rain, ensnared in barbed wire, entangled in numerous successive defensive lines, and decimated by machine-gun fire, offensives on the Western Front yielded little results and appalling casualties. The British and the French started looking for a solution to this ‘deadly equation’. The end result on the British end would be the first tank deployment in the world, preceded by the first tank prototype ever built, the ‘Lincoln No.1 Machine’.

The Lincoln No.1 Machine on trials. The tarpaulins concealing the vehicle have the name of the firm William Foster and Co. of Lincoln on them. Photo: SOURCE

A Historiographical Note

In October 1919, a Royal Commission on Awards to Inventors investigated about a dozen claims with regards to the invention of the tank. The claimants included personalities such as Winston Churchill, R.E.B.Crompton, William Tritton, Eustace d’Eyncourt and other important persons in the development of the tank. A large prize was awarded to those that the Commission deemed to be the ‘inventors’, although such a complicated machine could not be ‘invented’ by only two men and was a concentrated effort. However, the works of this Commission have driven a large number of divergent claims with regards to the development of the tank, and thus of the Lincoln No.1 Machine as well.
Furthermore, the Lincoln No.1 Machine (even under its more famous Little Willie name), while eliciting a large deal of interest, especially due to the centennial of the First World War, has only been treated superficially in the specialised literature, being glossed over in favor of the iconic rhomboid tanks.

A Flurry of Ideas

The tank, as it crashed through the German lines in 1916, did not appear out of a vacuum. Armored cars had been built and showcased around Europe for more than a decade, even though in small numbers and often facing vitriolic opposition. However, the armored car was incapable of traversing no man’s land. Various tank-like vehicles were also proposed around the continent and were just as rigorously ignored.
A myriad of solutions were soon envisaged, including portable bridges, pedrails, steam rollers and huge wheels. The tracked-vehicle did not immediately emerge as the redeeming solution. In fact, on 17th February 1915, a committee from the War Office (not to be confused with the later Landship Committee of the Admiralty) attended a demonstration of a Holt Tractor at Shoeburyness, some 40 miles west of London. However, the members of the committee were highly critical of the vehicle, especially regarding the weight and costs of an armored vehicle based on the Holt tractor. And thus the army turned its back on the tank idea.

The Navy Steps In

One of the major users of armored cars on the Western Front was, quite surprisingly, the Royal Navy Air Service, or RNAS. The First Lord of the Admiralty, Sir Winston Churchill, had already joined the landship discussion in January 1915, with a letter to the Prime Minister speaking about armored steam tractors that would crush barbed wire, cross trenches, and deliver infantry to the enemy lines. While other fanciful ideas and ludicrous designs were discussed, on the 22nd February 1915, the Admiralty’s Landship Committee met for the first time under the chairmanship of Eustace d’Eyncourt, deciding to further look into two options, tracked vehicles or vehicles with large wheels.
With no reliable tracks available in Great Britain at the time, an officer was sent to the USA to try and locate some. The mission resulted in the delivery of the Killen-Strait tractor followed by two Creeping Grip tractors and an elongated set of tracks from the Bullock company in Chicago. The Bullock tracks arrived in August 1915.

An excellent shot of the two of the two Bullock Creeping Grip tractors that were bought on behalf of the Landship Committee and linked together. This was a development parallel to what would become the Lincoln No.1 Machine. However, this photograph of the original suspension also demonstrates the sagging that the elongated version on the Lincoln No.1 Machine suffered from. Because the tank’s tracks were much longer, they were even more likely to not connect correctly on the far end of the trench and be thrown off. Photo: IWM
In June 1915, the Army finally expressed its interest in getting back into the project, but the development would remain in Admiralty hands for a while longer. On 22nd (other sources state 24th) of July, the Lincoln-based William Foster & Company was finally contracted to build a prototype landship based on the longer version of the Bullock tracks. This choice came due to their previous experience with building tracked vehicles and their involvement with the military, having developed the humongous Daimler Foster artillery tractors and also having been involved in developing their own trench-crossing vehicle.
The vehicle at this stage is also described as based on one half of the articulated Crompton machine, as in an order from the Landship Committee from the 30th of July. This did not mean it actually was one half of the Crompton machine, but just that it used the same tracks.
However, from this short incubation period in the Navy’s berth, a number of components of the tank have received ship-like designations that are in use to this day. Tanks have hulls (from the watertight shell of a ship), hatches for the crew members, sometimes have weapon ports and sponsons (a part of a ship that projects beyond the side of the hull), one or more turrets (an entirely enclosed part of a ship that could rotate with the armament mounted in it), the hull machine-gun is often called a bow MG (the bow is the front of a ship) and the part above the engine is the engine deck (the floors on a ship).

The Lincoln No. 1 Machine

The paternity of the design that emerged is contested, with both R.E.B.Crompton and William Tritton claiming it. The former had led the design efforts of the Landship Committee before his contract ending prior to the end of the construction of the prototype and he was replaced with Tritton. What is known is that Tritton at least knew of a set of detailed drawings done by Crompton and an assistant, Mr. Rigby. Tritton contests having received a full set of detailed drawings, with other sources claiming he did, in fact, receive them. Regardless, construction finally began on 11th August. On the 9th (or 8th) of September, just four weeks later, it was already being driven around the yard at the Foster Company’s testing grounds.

The Lincoln No.1 Machine during trials. Notice the turret visible under the canvas and what looks like a gun holding up the cover. The vehicle was going over a small hill. The steering wheels are visible at the rear, as is the ‘nose’ that protrudes in front of the tracks. Note that the image was improperly scanned. Source: IWM Q 14543

The Name

The vehicle presented in this article, featuring the Bullock tracks, the simple version of the rear wheels and the large turret, was known as either the ‘Lincoln No.1 Machine’, after the locality it was built in, or the ‘Tritton’, after its head designer, at the time of its construction and testing. Some sources also state that William Tritton called both this design and Mother as ‘Juggernaut’.
The ‘Little Willie’ nickname seems to have only appeared after the Tritton tracks were fitted, sometime in January 1916, accompanying the ‘Big Willie’, better known as ‘Mother’ or ‘His Majesty’s Land Ship Centipede’. There is no proof that the vehicle ever officially ceased being called the ‘Lincoln No.1 Machine’, even after its upgrade.
It is thus the author’s choice to use the designations to differentiate between the ‘Lincoln No.1 Machine’ fitted with the Bullock tracks and the ‘Little Willie’ fitted with the Tritton tracks.
A note on the ‘tank’ designation should also be made. The persons involved in the project decided to adopt a cover name for the new vehicle being prepared, ‘landship’ being deemed as too conspicuous. ‘Water Carrier’ was first proposed, but the shorter version of ‘tank’ eventually won out and has remained in worldwide use. It is, however, unclear when the ‘tank’ designation first appeared and if it was applied to the Lincoln No.1 Machine. J.F.C. Fuller, in his book ‘Tanks in the Great War 1914-1918’ claims that it was first used on 24th December 1915 for a proposed ‘Tank Supply Committee’ that would take over armored development in the United Kingdom. This Committee was indeed formed in September 1916 upon the dissolution of the Landships Committee.
Another explanation given for the tank name is that the ‘chassis’ and the ‘body’ of the vehicle were separated, with the ‘chassis’, actually the Creeping Grip track system, being described as a training vehicle for the Royal Marine Artillery and the hull of the tank as a water carrier for Mesopotamia. This could also explain the photograph of the Lincoln No.1 Machine hull in the Foster factory, showing an almost complete vehicle, but with no running gear and no holes cut into the hull.


The large, boxy vehicle was of riveted construction using an iron-angle frame, being made out of boiler plate and not bullet-proof armor. This was, in the end, meant to be a test prototype and not to see combat. An angular nose protruded from the front, inside which the steering controls were located. Just above the glacis of this ‘nose’ were two hatches, hinged on the upper part, which allowed the driver and co-driver to see forwards. Both these hatches also featured a small horizontal slit with a shutter that should have allowed some limited visibility under fire. A similar design would be kept for most British tanks used in World War One. These could be held open using a strut. It is unclear if the circular gun slot that later appeared between the two hatches on Little Willie was present on the Lincoln No.1 Machine as well or if it was a later modification.
Two large, almost full-length sponsons were present on the sides, emerging from just over the tracks and reaching up to the top of the vehicle. Each of them had three weapon ports with a rotating shutter when not in use. One large headlight could be mounted on either side. The rear of the tank hosted the coupling that held the rear pair of wheels. This coupling allowed the wheels to be turned from the inside through a small hole at the rear of the tank. The rear assembly was fixed to mounting points on each side at the rear and connected to a large spring in the lower part of the rear. A door was also present on the left side of the tank, with a pistol port at its top. This seems to have been the only way of accessing the tank. A radiator fill port was present on the upper right side.

A photo showing the rear of the Lincoln No.1 Machine. The rear wheels and their mechanism are visible, as is the cable used to control them. The large door on the left is open, probably in order to aid ventilation inside. The small tubular piece of metal protruding out of the oval port hole in the center of the right-hand door at the back of the vehicle is the radiator filling tube. The constant use of a large canvas sheet over the vehicle was for security purposes, meant to disguise the machine. Photo: SOURCE
The rear wheels were meant to help the tank in steering and could be turned left and right, like on a regular car. They were based on the Ackerman steering geometry used in most wheeled vehicles. Because they were at the rear, when the wheels were turned to the left they would then turn the tank to the right, similar to how a car handles when driven in reverse. This was not the main means of steering, but was meant to augment the track steering and allow for more efficient shallow turns. The usual brake differential, which was the main mode of steering, led to the loss of a good deal of the tank’s power. Also, when crossing a trench, the wheels would offer extra support to the tank, allowing it to pass over trenches and not slide backward at the last moment.
The rear wheels on the Lincoln No.1 Machine were the same as the front wheels on the Foster-Daimler tractor, with a prominent circumferential central rib on the wheels. This feature would be kept for the Mark I tanks, but was removed afterward. The wheels where 1.37 m (4 ½ ft) in diameter. A large coil spring was also present, one end connected to the rear of the hull and the other to the rear wheel frame. This spring pulled the wheels downward, ensuring good contact with the terrain. The Lincoln No.1 Machine did not have the hydraulic system that could raise the rear wheels when needed.

The rear wheels on the Lincoln No.1 Machine. The attachment points and the large spring that held them in place are visible. Photo: SOURCE
The top of the tank had five structural support ribs running transversely, with another reinforcement running longitudinally on the centre. There was a radiator air intake at the rear right. A fan intake was placed further forward on the right, but behind the turret. Two more holes were present next to the fan. One of them was probably the fuel intake and the other the exhaust, although that is just speculation.
The Lincoln No.1 Machine also featured a large circular turret placed near the middle of the vehicle. There is some discussion around the placement of the turret, focusing on whether it was centered or offset to one side. Investigations on Little Willie, which survives in the Bovington Tank Museum, show that the circular plate that was used to cover the turret opening is off-center. However, it is unclear if this is because the turret opening itself is off-center or if only the plate was mounted to one side.
David Fletcher, in ‘The British Tank: 1915-1919’, states that the turret did not have any rotation mechanism installed for the prototype. It was not just a dummy weight though, as a photo taken during construction of the vehicle shows it being made of riveted steel, same as the rest of the tank. Contrary to various online opinions that state that the turret was meant to be fixed in place, it was almost assuredly designed to rotate on the final design. Turrets were not a new concept at the time, having already been used extensively on armored cars and on ships. Furthermore, the circular shape was too difficult to create and had no advantages over a rectangular shape if it was meant to be a fixed casemate.
Unfortunately, little else is known about the turret except for the fact it had at least one more weapon port. There is also a chalk lining on the front part, possibly showing where the cut-out for the gun would be made. There is a single photo showing the turret during the construction of the Lincoln No.1 Machine. The turret is well hidden by a textile cover in all the other photos of the vehicle. This was meant to obscure the role of the vehicle to any uninvited enquirers.

The only photo showing the Lincoln No.1 Machine’s turret. This was taken during construction at William Foster and Co. Note that the front hatches for the driver and co-driver have not been cut in yet. Neither have the side gun ports. The ‘tube’ sticking out of the lower side of the hull next to the ladder is the central pivoting axle, on which the track frames where mounted and also supported one drive chain sprocket. It is unclear what the thing attached to the side of the hull is, although it is possible it was used for cutting the weapon ports. Photo: SOURCE
The running gear was not directly connected to the hull of the vehicle. All the wheels that held the track were mounted on a frame that was then connected to a central pivoting axle on each side. Two other brackets on each side, one at the front and one at the rear, controlled the pitch of the body.


The Lincoln No.1 Machine was meant to sport impressive weaponry for the time. The turret was intended to mount a Quick Firing (QF) 2-pounder (40mm) Mark II gun. This watercooled Vickers-Maxim type autocannon was already in use in the Royal Navy as a ship-borne anti-aircraft gun. This weapon had a relatively high-rate of fire, being belt-fed, and a high muzzle velocity (585 m/s). However, the rather small shell had no explosive power, its main ammunition being solid shells, and would have struggled against enemy emplacements and machine-gun nests. This would lead to its abandonment by the nascent tank arm in favor of the 6-pounder.
Another machine-gun was meant to be mounted in the weapon port to the left of the gun. This was not coaxial and could be independently aimed.

A Quick-Firing 2-pounder (40mm) gun used as an Anti-Aircraft Gun on a train car in the Middle East, in Mesopotamia, in 1918. Photo: Q 24291, Imperial War Museum archives
Besides this, up to six Madsen light machine-guns were meant to be used. The hull of the Lincoln No.1 Machine had three pistol ports on each side and another one at the rear, from which the machine-guns were probably meant to be fired. They would be mounted on trunions and aimed through special sights using a short pistol grip. The barrel would have had a special cover. The machine-guns were magazine fed, with the magazine on the top part of the weapon. It can be speculated that the machine-guns could be dismounted for use outside the tank if needed.
The Madsens had been ordered from Denmark in 1914 for land and air use, but they were never shipped to Great Britain because the route was well covered by the German High Seas fleet and submarines. The Madsens were subsequently abandoned by the time the Tank Mark I rolled out at Flers-Courcelette, replaced by the locally-built Hotchkiss and Vickers machine-guns.

The tank version of the Madsen light machine-gun. Photo: The Madsen Machine Rifle. Main Characteristics, Organization and Tactical Use
Another source, ‘Lincoln No.1 Machine, Little Willie’ by M.J.Verrall, states that the machine-guns would be Lewis or Hotchkiss ones. The same source also states a Maxim machine-gun would have been fitted in the circular port at the front of the tank.
Some sources also state that some rifles would be carried, probably for use by the crew if they dismounted. Ammunition capacity and stowage are unknown. It is almost certain that the Lincoln No.1 Machine never got to the point where these were even considered.


The engine used in the Lincoln No.1 Machine was the same 105 hp Daimler-Foster already in use on Foster’s gigantic artillery tractors. This was a six-cylinder sleeve-valve petrol engine. The sleeve-valve system was an alternative to the currently usual poppet valve. These devices are used to control the flow of fuel into the piston.
At its invention, the sleeve-valve engine was significantly quieter and had markedly improved reliability, being a favorite for luxury machines. This came at the cost of excessive lubricating oil use. In the end, availability, Foster’s experience with the engine and the fact it was already in production and could be put into new tanks quickly led to its use in the Lincoln No.1 Machine.

A 1913 article from The Commercial Motor magazine showing a photo of the 105 hp Daimler engine that was later used in the Lincoln No.1 Machine. Photo: Commercial Motor April 1913
The engine was placed towards the rear of the tank, partially underneath the turret, which would have made the latter’s use more complicated. This peculiar arrangement was probably chosen in order to give a better weight distribution and allow better crew access to the engine.
Beside the engine, a gearbox (two forward speeds, one reverse), a worm differential, steering controls, and a radiator were also present. The radiator was placed at the rear-right of the vehicle and the differential was probably placed in the middle part of the vehicle. The steering controls were at the front, close to the two driver positions. One driver controlled the acceleration, gearbox and rear wheels, while the other one controlled the brakes for each track. Two fuel tanks were mounted in the rear upper sides of the hull.
The power transfer arrangement from the differential to the drive sprocket was ludicrously complicated. The drive shafts (one on each side) had a sprocket connected through a chain to another sprocket fitted to the central pivoting axle. This was connected to a second sprocket, also fitted to the central pivoting axle, which was connected by a second chain to a lantern pinion that drove the drive sprocket at the rear of the tank. A similarly complicated system was maintained on the subsequent Tank Mark I-IV. This had the advantage that the whole power transfer arrangement was more resistant to shocks, since the chains would not transmit exterior shocks to the gearbox and differential.

Illustration showing a cutaway of the complicated power transfer arrangement on the Tank Mark IV. Photo: Source unknown, taken from Pinterest

The slightly less complicated power transfer arrangement on the Tank Mark V, showing the two chain-connected sprockets, the second of which meshes with the drive sprocket. Photo: The Tank Corps, by Major Clough Williams-Ellis, M. C., and A. Williams-Ellis

A Daimler Foster artillery tractor. The size of this machine is immediately apparent. The engine and front wheels were reused on the Lincoln No.1 Machine. OHMS stands for On His Majesty’s Service. Photo: SOURCE


The number of crew members that the Little Willie would have accommodated is given as five in a single source, a speech given at an anniversary dinner 50 years later for the designers. It is unclear how accurate this information is. Two crew positions were present at the front of the vehicle, for the driver and the co-driver. At least two more crewmen would have been present in the turret, with the other one (or possibly more) manning the machine-guns in the sponsons.

The Track Units

The entire track system of the Lincoln No.1 Machine was imported from the United States, from the Bullock company of Chicago. They were an elongated version of the tracks used on the Creeping Grip tractor built by the same company. This was done because there were no suitable track producers in the United Kingdom and due to expedience, as they were already in production (even though thousands of miles and an ocean away).

The Bullock ‘Creeping Grip’ short tracks, as used on the original tractor. Photo: Commercial Motor magazine, 3rd April 1919
The drive sprocket was at the rear, while the idler was at the front. They both had a distinctive, slightly-spiraled design and were cast. The idler could be used to adjust the track tension. Eight equally-spaced small road wheels held the weight of the tank. These were all held on a single fixed frame. All photos of the Lincoln No.1 Machine show a significant curvature of the roadwheel line. This was apparently done in order to reduce the amount of track in contact with the ground and thus allow the tank to steer. There is indeed an inverse relationship between the contact length of the track and the ease of steering. The return of the track was supported by five return rollers, all fixed to another metal frame. This upper metal frame was connected to the arms of the idler and drive sprocket.
However, telegrams between Crompton and Wilson, sent when the Bullock tracks reached Foster’s, indicate that the tracks did not initially have this curvature, despite it being specified in the order to the Bullock company. This change was done on the 10th of August by lowering the central roadwheels.
There were apparently no springs or suspension parts, which assuredly made for a very bumpy ride. The vehicle was meant to be able to overcome a 1.5 m (5 ft) trench or a 75 cm (2 ½ ft) parapet.
It is interesting to note that all the running gear elements were connected to the ‘Creeping Grip’ frame and not directly to the hull of the Lincoln No.1 Machine. While this certainly affected the resistance and characteristics of the running gear, it nevertheless meant that it was easy to change, as was done when the Tritton system was introduced.

The Lincoln No.1 Machine during trials, showing an excellent view of the tracks. A close examination of the image shows that the first roadwheel has already disconnected with the tracks, landing on the outside of the guide horns when it should have stayed on the inside. Photo: SOURCE
The track links themselves were quite interesting. They were made from cast manganese steel and were 61 cm (24 in) wide. On the inner part, they had four sets of guide horn plates, which ran on either side of the wheels, idler, sprocket and return rollers. This was done in order to decrease the likelihood of the tank throwing its track. These guide horn plates also appear to have been able to rotate slightly in order to accommodate for the large curvature of the track at the front and rear.
The Bullock tracks were poorly manufactured. A report from the official that visited the Bullock factory claimed that, when the tracks did not fit the drive sprocket, the workers solved the problem by hammering the tracks into submission. Nonetheless, the tracks seem to have been unable to handle the larger weight of the Lincoln No.1 Machine and snapped or fell off as soon as the machine started moving in the factory. It must be noted that the vehicle was expected to have an operational life measured in tens of miles in order to accomplish its tasks of crossing the no-man’s-land and engaging the enemy defensive lines.
A larger problem became evident when crossing trenches. As the vehicle crossed the gap, the tracks sagged from under the wheels. When coming on the other side of the trench, the track guide horns would fail to properly connect with the wheels, which would land to the side of their intended central location. This lead to the track being thrown. During tests, this happened with alarming regularity and was, in the end, the downfall of the Creeping Grip track system, which was dropped in favor of a local design. This problem seems to have been due to the lateral flexibility of the tracks themselves.

The Lincoln No.1 Machine going up a slope during trials. Photo: SOURCE


The Lincoln No.1 Machine was tested at Cross O’Cliff Hill, just south of the Lincoln town, on the 19th of September 1915, with Sir Eustace Tennyson d’Eyncourt, Lieutenant-Colonel Ernest Swinton, Major Walter Gordon Wilson, First Lord of the Admiralty Winston Churchill, and others in attendance, including a large crowd of factory workers and their wives. Most of the vehicle was covered with three large textile canvases from the Foster factory. One was suspended over the nose of the vehicle and a larger one was draped over the turret and the hull roof except on the rear-right side. The last canvas hanged from the side of the vehicle on the rear right side. This left the rear-right of the tank’s roof uncovered, allowing the exhaust and fans to function unobstructed.
The vehicle was run through difficult terrain and trenches. However, the tracks were repeatedly thrown off when trying to cross trenches, while the track links themselves were unsuited for the weight of the vehicle and began to break off.
This lead to the abandonment of the Bullock tracks, which were replaced with a new design on the second version of the prototype, now known as the Little Willie. However, by this time, the lozenge-shaped tank concept had already entered development and Little Willie was just a track testing vehicle.
Apparently, the rear wheels also proved unsatisfactory in some way or another, as they were changed to include a hydraulic system. More problems that were identified during tests regarded the turret, which made the tank top-heavy and too tall. It was subsequently abandoned.

Illustration showing how the Lincoln No.1 Machine might have looked during its tests without the canvas cover. Behind it is the Foster Daimler tractor, from which the engine, transmission and front wheels were reused on the tank. Illustration by Tony Bryan, taken from British Battle Tanks: World War I to 1939 by David Fletcher.

The Lincoln No.1 Machine during trials. The two openings at the front are clearly visible, although the hatches themselves seem to be missing. This photo shows the outer side of the tracks, which were of poor quality. Photo: IWM Q 14542

Little Willie specifications

Dimensions (L-w-h) 5.87×2.86×2.51 m (19x9x8 feet)
Total weight, battle ready 16.5 tons
Crew 6
Propulsion Foster-Daimler Knight sleeve valve petrol 105 hp
Speed 3.22 km/h (2 mph)
Range/consumption 30 km/800 liters (18.64 mi)
Armament Vickers 2 Pdr (40 mm) Mk. II
6 Vickers 7.7 mm (0.303 in) machine guns
Armour From 10 to 15 mm (0.39-0.59 inches)
Total production One prototype


‘The British Tank: 1915-1919’ by David Fletcher
‘Osprey New Vanguard 100, British Mark I Tank 1916’ by David Fletcher
‘AFV Weapon Profiles 3, Tanks Mark I to V’ by Chris Ellis and Peter Chamberlain
‘A New Excalibur: The Development of the Tank, 1909-1939’ by A.J.Smithers
‘The Tank: Its Birth and Development’ by William Foster and others
‘The Landships of Lincoln’ by Richard Pullen
‘Eyewitness, being personal reminiscences of certain phases of the Great War, including the genesis of the tank’ by Major-General Sir Ernest D. Swinton.
‘History of the Tank’. Dinner Speech on the Commemoration of 50 years since the first use of tanks. January 1977
‘Lincoln No.1 Machine, Little Willie’ by M.J.Verrall, October 1988
‘The Madsen Machine Rifle. Main Characteristics, Organization and Tactical Use’
The Commercial Motor, A SIX – CYLINDER 105 h.p. SLEEVE-VALVE DAIMLER, 3rd April 1913, Page 14
The Commercial Motor, 3rd April 1919
This entire article has been funded by our Patron Golum through our Patreon campaign!

The Lincoln No.1 Machine, sporting the round turret armed with a 2-pounder Pom-Pom gun. Two more Madsen machine-guns are sticking out of the side sponson ports. Illustrated by Bernard ‘Escodrion’ Baker, funded by our Patron Golum through our Patreon Campaign.

Little Willie – Tank Encyclopedia Support Shirt

Little Willie – Tank Encyclopedia Support Shirt

Little Wille, the first tank prototype, features prominently in this snark shirt! A portion of the proceeds from this purchase will support Tank Encyclopedia, a military history research project. Buy this T-Shirt on Gunji Graphics!

Col. R.E.B. Crompton (Pioneers of Armour)
Col. R.E.B. Crompton (Pioneers of Armour)

By Andrew Hills

The foundations and principles of modern armoured warfare did not appear out of a vacuum, and nor did the machines of WW1 and WW2. Their development was full of false starts, failed ideas, and missed opportunities. Rookes Evelyn Bell Crompton was a pioneer in electrical engineering and road haulage who, by the turn of the century found himself in South Africa during the Boer War. Later, in WW1 his early work with the Landships Committee on tracked vehicles sought to break the stalemate of trench warfare. Although his tank designs never saw combat the work he started was carried on by other pioneers and helped to usher in a dawn of armoured and mechanised warfare.

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WW2 German SPAAGs


ww2 German half-tracks Nazi Germany (1939)
Half-Track SPAAG – 750

The most famous German self-propelled anti-aircraft guns (SPAAG) are the Panzer IV based Wirbelwind, Ostwind, Mobelwagen and even Kugelblitz. However, despite being overshadowed by their tank-based counterparts, it was actually the half-track SPAAGs that made up the bulk of the German mobile anti-aircraft fleet. Thousands of such lightly armored vehicles were built, based on different chassis and with different gun combinations.
One of the earliest examples of such a vehicle is the Sd.Kfz.7/1, a version of the ubiquitous half-tracked tractor armed with a 2 cm Flakvierling 38 anti-aircraft gun system.
An early Sd.Kfz.7/1 undergoing trials, with the Flakvierling gun system covered. Notice that the tarpaulin covering the driver’s compartment is fitted. Also notice the early mesh drop-sides and the tools attached to them. Source:

The Sd.Kfz.7

The Sd.Kfz.7, or Mittlerer Zugkraftwagen 8t (Medium Tractor 8 tonnes), was developed as part of the larger family of German half-tracks. The first specifications for this vehicle were laid down in 1932 by Wa.Prüf.6. The vehicle was developed by Krauss-Maffei, with the first vehicle entering production in 1933.
As the designation suggests, the Sd.Kfz.7 was meant to tow weights of up to 8 tonnes. It was the tow vehicle of choice for the famous Flak 88 anti-aircraft guns, the 15 cm sFH 18 howitzer, and the 10.5 cm K18 field gun. However, due to the chaos of war, these vehicles were sometimes seen towing larger loads. They also towed trucks and even light tanks through the harsh conditions on the Eastern Front. The Sd.Kfz.7 could also carry up to 18 men on its 3 benches. The rear of the vehicle was compartmentalized in order to carry various equipment, fuel and ammo.
The design constantly evolved during its 11 year production period. Several engines were used, with various changes made to the superstructure and suspension, including the addition of an extra pair of roadwheels with the last model, the Typ m 11, in order to reduce ground pressure.
In total, 12,000 Sd.Kfz.7 half-tracks were built by Kraus-Maffei, Daimler-Benz, and Hansa-Lloyd in Germany, Saurer in Austria, and Breda in Italy until 1944. They served on all front with the German Wehrmacht, as well as with Italy, Bulgaria, Hungary, and even the Yugoslav Partisans. Some were even used after the war by the Allies and the British tried to copy the design with the Traclat.
An Sd.Kfz.7 Typ m 11 towing an 88 mm Flak gun on a Sonderanhänger 201 trailer. This was a large and powerful vehicle and made a good basis for a SPAAG. Source:

The Sd.Kfz.7/1

The Sd.Kfz.7/1, also known as the ‘Selbstfahrlafette auf m.Zgkw.8t (Sd.Kfz.7/2) mit 2cm Flakvierling 38’, was born shortly after the 2cm Flakvierling 38 was presented to Adolf Hitler in October 1939. The Luftwaffe ordered 100 such weapons systems to be mounted on the Sd.Kfz.7 chassis. Production started in February 1940 and continued until December 1944, by which time between 750 and 800 were manufactured. This made the Sd.Kfz.7/1 one of the most numerous SPAAGs the Germans had at their disposal.
The prototype Sd.Kfz.7/1. The pivot mounting used on the initial vehicles is very visible in this photo. The Flakvierling is lacking its full gun shield. Source: Panzer Tracts 12
The rear two bench rows were removed, as was the luggage compartment. In their place, a flat platform was created, with the gun mount in the center. A bench row was placed at the front of the platform, facing rearwards. The platform had three drop-sides. These were vertical when the vehicle was on the move, creating a space for the gun crew to stay in. When in firing position, these were dropped into a horizontal position, thus enlarging the space the crew had to move in. The rear drop-side also had a small ladder that helped the crew climb or descend from the platform. There were two kinds of drop sides used. For most Sd.Kfz.7/1 vehicles, these consisted of wire mesh fixed on a metal frame. Some of these metal frames had diagonal braces. However, vehicles built late in the war had these made of wood on a metal frame. This was probably done in order to save materials.
The windshield could be dropped down in order to allow a larger arc of fire for the gun. A tarpaulin could be added to give some cover from the elements, but it only covered the driver’s section.
The winch placed under the vehicle seems to have been retained. It was used to pull vehicles or guns that had gotten stuck.
The Sd.Kfz.7/1 at Koblenz. This vehicle is a reconstruction, being based on a regular Sd.Kfz.7 recovered from France. It is a late version with an armored cab and wooden drop sides. Some tools are strapped to the bonnet. Source:
After August 1943, the vehicle was up-armored using 8 mm steel plating (although production of the unarmored version continued in parallel) and the official designation also changed to ‘Selbstfahrlafette mitgepanzertem Fahrerhaus (Self-propelled gun carriage with armored cab) auf m.Zgkw.8t (Sd.Kfz.7/1) mit 2cm Flakvierling 38’. However, only certain sections of the vehicle were protected. There were two plates at the front of the vehicle, covering the radiator and the engine from frontal fire. The sides were completely exposed. A new armored cab was also added, protecting the driver’s position and the rear crew’s bench. It was partly open to the rear. The top part was only 1.5 mm thick. There were four vision ports protected by armored shutters, two in the front windscreen and two in the side doors. The forward armored shutters had glass vision blocks built in. There were also two hatches in the roof of this armored compartment. There was an armored firewall between the driving compartment and the engine compartment. The armor weighed 2.2 tons. There were plans to prepare a lighter armored cab weighing only 800 kg.
Tools could be carried on the outside of the drop-sides, like a shovel or a pickaxe. However, these are absent in a large number of contemporary photos. Tools are also often depicted as being mounted on the engine hood on the up-armored vehicles, but, yet again, photographic evidence is lacking. One vehicle, restored by Krauss-Mauffei and stored at least for a time at Koblenz, features these hood-mounted tools.
The gun system was mounted in the middle of the rear platform. There were no less than 4 gun mountings used during production. The first one was a small tripod that was height adjustable. Then, the gun system was mounted on a pivot which was also height adjustable. The third mounting is unclearly described in the literature. However, on later vehicles, a new mounting system was added, which allowed the mounting of the gun system using its usual tripod. This had the advantage of easily allowing the Flakvierling to be dismounted and placed on the ground, but this option seems to have been rarely used. The tripod mount was bulkier and occupied more space than the pivot mount.
The later type gun mount. It could accommodate the Flakvierling directly on its tripod mounting. Source: Wheels & Tracks 12
A late Sd.Kfz.7/1 showing the tripod mount of the Flakvierling. This allowed the gun to be easily dismounted from the vehicle with the use of a crane. Source: Pinterest
The Sd.Kfz.7/1 also towed a Sd.Ah.56 special trailer. This was a two-wheeler trailer specially designed for carrying the ammo boxes and accessories for the Flakvierling AA gun system.
120 boxes of ammunition carrying 20 rounds each for a total of 2400 rounds were carried. 30 magazines were carried in the vehicles itself, with the other 90 being kept in the trailer. However, in operations, ammo boxes were scattered all around the rear platform, in order to allow easy access to the loaders.
A large number of chassis were also produced without the gun, meant to act as munition carriers. However, they had all the fittings needed to receive a gun and also acted as reserve chassis. It is unclear if these vehicles are included in the total production number or not.
A late version Sd.Kfz.7/1 with its Sd.Ah.56 trailer. Note the large amount of vegetation used as cover. Also, the steps are visible on the rear drop-side. These were used to access the platform. Source: Bundesarchiv via Wikimedia Commons


The Sd.Kfz.7/1 kept all the automotive parts from the Sd.Kfz.7 half-track. The SPAAGs were based on the KM m 11 or the HM m 11 versions, the last in the evolution of the Sd.Kfz.7.
The original engine was a Maybach HL 62 TUK, although this was changed in 1943 for the HL 64 TR. The difference between the two was the displacement (6.4 liters instead of 6.2 liters) and the change of the lubrication system. Both were 6-cylinder water cooled gasoline engines. The HL 62 could reach a maximum of 140 hp at 2600 rpm. It could power the Sd.Kfz.7/1 to a maximum speed of 50 km/h. The 203-liter fuel tank gave a range of 250 km on road.
The engine was connected to a 5-speed differential gearbox (4 forward, 1 reverse) that powered the drive sprockets mounted at the front of the track. This was an “Aphon” type non-synchromesh gearbox. The clutch was a Mocano K 230 K. Seven pairs of interleaved rubberized roadwheels provided contact with the ground and also held the track on the return run. Six of the roadwheel pairs were sprung using a leaf spring suspension. However, the last pair, which also acted as the idler, had a torsion bar suspension instead.
One of the suspension units of an Sd.Kfz.7. Four pairs of roadwheels were connected to this leaf spring. Another two pairs were connected to another leaf spring, while the last pair was connected to a torsion bar suspension. Image courtesy of the Sd.Kfz.7 Project Part Search
Steering was achieved using the front two wheels. These were air-filled rubber wheels that were steered using the steering wheel in the driver’s cabin. The tracks could also be powered separately in order to help turning, but this was used only if the steering wheels were insufficient. The front wheels had a leaf-spring suspension

The 2cm Flakvierling 38

The Flakvierling 38 anti-aircraft mount system was introduced into service in 1940. It was developed by the Mauser company for the Kriegsmarine at first but was then adopted by the Wehrmacht in order to provide an anti-aircraft system with a better rate of fire. It consisted of four 2cm Flak 38 AA guns mounted together, two on each side. This allowed the Flakvierling to put up four times more bullets in the same amount of time compared to the single Flak 38, thus increasing the chances of severely damaging enemy airplanes.
Inadvertently, this also made the gun quite potent against ground targets, as it was able to saturate enemy positions with fire.
A color (or colorized) image of a Sd.Kfz.7/1 in a very warm climate. Notice the vegetation piled up around the vehicle to provide some sort of cover. Source:
There was no central loading system and each gun had its own 20 round magazine. The magazines were mounted on the sides of the system. When the system was at 0 degrees elevation, the magazines were horizontal.
The guns had a maximum range of 4.7 km and a maximum altitude range of 3.7 km. The combined maximum rate of fire of the 4 guns was 1800 rounds per minute, but this was usually closer to 800 rpm in operation, as the guns needed to be reloaded after they finished their magazines. It could take as little as 3 seconds to fire off all four magazines. Special compartments for the magazines were present on either side of the mount, rotating along with the whole system. The gun barrels could be removed for cleaning.
The guns were fired with the use of two-foot pedals. Each pedal fired two diagonally-opposed gun, so the upper-left at the same time as lower-right. This was done in order to balance out the firing recoil. If a pedal would have controlled the guns on one side, then the recoil from firing them would have rotated the mount to one side, thus making it impossible to aim. If the pedal would have controlled the guns on the upper part, the recoil would have pulled the system upwards, again throwing off the gunner. With the guns fired in diagonal pairs, the recoil compensated both horizontally and vertically, allowing the gunners to aim properly at their target. An official order was issued to Flakvierling 38 crews to only fire two barrels at a time, but this recommendation was mostly ignored in the field.
An Sd.Kfz.7/1 gun crew looking after one of its targets prior to the Battle of Kursk, 1943. Notice the large amounts of vegetation used as camouflage. Source: ww2dbase, German Federal Archive
The aiming system consisted of either a Flakvisier 38 or a Flakvisier 40. They differed in minor details. These were electrical devices which used batteries to adjust the sights in order to help the gunners aim.
The Flakvierling could rotate 360 degrees, with elevation ranging from -8 to 85 degrees. Both rotation and elevation were done manually. The first Sd.Kfz.7/1 were not produced with a gun shield, but this was introduced quite early and retrofitted to older vehicles. The guns were protected by a 3-part shield, with the outer sides being dismountable. The shield weighed 325 kg. These offered the gunners and loaders a degree of protection from rifle-caliber bullets. For land use, the whole system sat on a static tripod which had a ring on which the system rotated. When used on ships, the system sat on a pivot. No fewer than 10 men were needed to crew the Sd.Kfz.7/1, with a driver, a commander and 8 gun servants.
A well worn early Sd.Kfz.7/1. The Flakvierling is lacking two of its barrels. The vehicle has received a coat of white-wash as camouflage. Notice the wire mesh drop sides and the tools still attached to it.

By the end of the war, the Flakvierling became less efficient against the newer versions of the Allied and Soviet ground attack planes, thus falling out of favor and being replaced by 3.7 cm guns. This was probably one of the reasons why the Sd.Kfz.7/1 was discontinued in 1944.

SdKfz-7/1 Flakvierling
SdKfz-7/1 Flakvierling by Tank Encyclopedia’s own David Bocquelet
SdKfz-7/1 with armoured cab
SdKfz-7/1 with armoured cab by Tank Encyclopedia’s own David Bocquelet

Markings and Camouflage

* Most of this information comes from photographic records.
The early war vehicles seem to have been painted in the regular Dunkelgrau color used for most German army vehicles at the time. Three license plates were fitted to the vehicle, two on the front bumper and one at the rear. No other markings seem to be present on the vehicles.
During winter, the Sd.Kfz.7/1 were white-washed in order to make them harder to detect by enemy pilots and ground troops.
The vehicles soon acquired various camouflage schemes, although it is unclear if these were regulated or purely the crew’s choice. A set of full-color pictures taken in Czechoslovakia in May 1945 of the surrender of the I. Flak-Korps show a number of Sd.Kfz.7/1 SPAAGs in green-sand camouflage colors, although the patterns are quite random.
Two uparmored Sd.Kfz.7/1s from the I.Flak Korps surrendering in Czechoslovakia in May 1945. These are original color photos and beautifully show the camouflage colors used. Source:
An interesting feature on a number of vehicles is that the gun shield was covered with cloth, probably in order to minimize reflections that might give the vehicle’s position away. Also, large amounts of vegetation were used to camouflage the vehicle and make it harder to see from the air.
Markings were quite rare. One vehicle was photographed with kill marks on the gun shield, indicating the number of plane and ground vehicle kills the crew claimed. One other late-style vehicle has the nickname ‘Dorle’ written on the radiator armor plating. Another vehicle, from a leichte Flak-Btl., had some markings denoting its unit on the front fenders. An up-armored Sd.Kfz.7/1 had unit markings on the right cab door. However, these occurrences were the exception and not the rule.
An Sd.Kfz.7/1 with the gun shield covered by cloth sitting in a cereal field. This was meant to remove any reflections from the metal shield which could give away the position of the gun system. The two sunflowers are also an interesting addition. Source: German Self Propelled Guns, Armor at War series 7022
An Sd.Kfz.7/1 also surrendering in Czechoslovakia. Notice the ‘Dorle’ nickname stenciled on the front armor plate. Source:

Operational Use

The Sd.Kfz.7/1 was used by the Flak Kompanies and Flak Batteries of the Luftwaffe. These were used to accompany the Wehrmacht’s divisions or to protect important locations and installations like airfields. Two or three Sd.Kfz.7/1 SPAAGs formed a platoon. After 1943, a three-vehicle platoon was also added to the HQ unit of each Panzer Abteilung. This gave the tank units their own AA support, without having to rely on the Luftwaffe’s.
These vehicles were very well suited to accompany the German Panzer formations, as they could keep up with the tanks. Also, they could deploy very quickly, immediately providing cover for the troops in case of an unexpected air attack. A towed AA gun would first have to be taken off its trailer and then be placed on its mounting, which would take precious time during an attack. Also, the Sd.Kfz.7/1 could withdraw quickly if the situation required it, with little preparation required. As a trade-off, the Flakvierling could be towed by far smaller vehicles, meaning that the creation of a SPAAG meant the loss of a powerful tractor which could be used to tow a heavier piece of ordnance. This was especially important given the fact that, throughout WWII, the Wehrmacht was reliant on horses to tow their heavy ordnance, as there were never enough heavy tractors.
Their very high rate of fire made them a significant threat to enemy ground attack aircraft. Besides their potential to destroy the attackers, their presence could make enemy pilots hesitate or rush their attack runs, thus lowering their chances of success.
The Sd.Kfz.7/1 had a very high silhouette. Besides obviously making it more visible, this also made it harder to dug-in compared to the towed Flakvierling, as the whole tractor had to be accommodated under cover. Also, for the up-armored vehicles, the guns could not fire directly in front of the vehicle, creating a blind spot.
However, their lack of armor meant that they had to avoid enemy ground forces, as the initial batches of vehicles were vulnerable to all small arms fire and to artillery shrapnel. Even the later vehicles, although up-armored, were only protected against small arms fire coming from the front.
Despite these flaws, the Sd.Kfz.7/1 found itself pressed into a role it was definitely not suited for: fighting against enemy ground forces. In the ground fire support role, the Flakvierling could be a serious threat to enemy infantry and unarmored vehicles due to its high rate of fire and high caliber. Also, when using AP rounds, the Flakvierling could penetrate light armored vehicles such as armored cars or the shields of AT guns. When used in this role, the vehicle was driven in reverse, with the gun having a free field of fire towards the enemy. This did offer the advantage of a quick getaway if needed. Also, the armor of the vehicle was definitely insufficient for the task, with the crew members, especially the loaders, being protected only by the gun shield.
An Sd.Kfz.7/1 on the Eastern Front, being used in a counter-attack against Soviet forces. The vehicle is being driven in reverse, with the gun facing towards the rear. Note that it is an early type vehicle, with no armor whatsoever except the gun shield. Source: Gepard: The History of German Anti-Aircraft Guns
The Sd.Kfz.7/1 soldiered for most of the war, serving especially on the Eastern Front, but also in Africa, Italy and the Western Front after 1944. It is, as of now, unclear if these vehicles served in the invasion of France or Norway.
One famous occasion in which an Sd.Kfz.7/1 was used was during operation Market Garden. Then, a vehicle from an SS unit used its guns to fire at airdropped paratroopers while they were still in the air, but also at the supply gliders.

Surviving Vehicles

At least three Sd.Kfz.7/1 exist today in museums. One late version with the armored cab is at the Koblenz Armor Museum in Germany. This is not an original vehicle, but a reproduction. The base vehicle was an Sd.Kfz.7 recovered from a scrapyard in France where it had been used as a heavy load tractor. It was refurbished with the help of a number of German military defense companies, including Krauss Maffei (who paid for the reconstruction), MTU (engine), ZF Friedrichshafen (transmission), and Clouth (roadwheels).
A second vehicle is at the Sinsheim Technical Museum in Germany, being an early unarmored version. The gun shield is probably a later addition and does not match the usual Flakvierling shield.
The third vehicle is at the Saumur Tank Museum in France. It is awaiting restoration and, while visually in a bad state, the chassis and automotive parts are claimed to be in good order. It is a late war version with the armored cab. The Flakvierling 38 on the back seems to be missing.
The Sd.Kfz.7/1 at the Sinsheim Technical Museum. Source:
Sd.Kfz.7/1 at the Saumur Tank Museum, awaiting restoration. Image courtesy of Christophe Mialon.


Dimensions (L-W-H) 6.85 x 2.35 x 2.62 m (22.6 x 7.9 x 8.7 ft)
Total weight, battle ready 11.5 tons
Crew 1 Driver + gun team
Propulsion Maybach HL 62 TUK, six-cylinder petrol
Suspension Half-track torsion arms, interleaved wheels
Maximum speed 50 km/h (31 mph)
Armament 2cm Flakvierling 38
Total production 750

Links, Reources & Further Reading

Panzer Tracts No.12: Flak Selbstfahrlafetten and Flakpanzer, Thomas Jentz, 1998
Panzer Tracts No.22-5: Gepanzerter 8t Zugkraftwagen & Sfl. Flak (Sd.Kfz.7), Thomas Jentz
Gepard: The History of German Anti-Aircraft Tanks, Walter Spielberger, 1982
‘Sd.Kfz.7 turned 7/1’, Walter Spielberger, Wheels & Tracks 12, 1985
German Half-Tracked Vehicles of World War II, John Milsom, 1975
Panzer Regiments: Equipment and Organisation, W.J.K Davies, 1978
Information about the Flakvisier from Handbook on German Military Forces, US War Department, 1945
20 mm Flak 38 on WW2-Weapons, written by WW2-Weapons team, consulted 29 December 2017
Deutsche Artillerie-Geschuetze, Alexander Lüdeke
War Office Tech Intell Summary No. 151, November 8th 1944
ETO Ordnance Technical Intelligence Report No.220, 11 April 1945
Special thanks to the Sd.Kfz.7 Project Part Search for information about the suspension, to Mr. Hilary Louis Doyle for naming information, to Christophe Mialon for information about the vehicle at Saumur
Special thanks to Hunter12396, CaptianNemo, Craig Moore and Marcus Hock for help in searching for information and sources