There is no doubt that working in the field of espionage is a difficult occupation. Human intelligence sources are often unskilled or untrained and their information requires vetting and assessment. Even technical intelligence from eavesdropping or copying of documents is fraught with errors, counter-intelligence, mistakes, and, sometimes, complete fabrications. Experts in one field may not be experts in others and ‘fake’ information can be obtained even from an honest and reliable source who has been ‘fed’ fake information by the other side. This interplay of espionage and counter-espionage intelligence work can produce its fair share of false intelligence and the ‘Turtle’ tank of 1951 is certainly a contender in this category.
Before a substantive discussion on the technical elements of the Turtle tank, it is worth examining the one and only source for this information. It comes from the reading library of the Central Intelligence Agency (CIA) and, whilst still heavily redacted to protect the identity of the source, it provides some data on which to vet the information.
The source of the data is a group of unnamed ‘German experts’ examining a report from an informant. The German experts are not identified and it is not known in which field they have expertise. It is a reasonable assumption, however, that their expertise is in the arms industry, as not only do they provide a technical evaluation of the ‘Turtle’ but also relate some information that this relates to improvements of a design first identified in 1943, during the war. Further, the CIA would have no reason to hand a report from an informant to some experts if they were not specialised in armored warfare in some capacity.
The expert analysis states categorically that the design shown is impractical and not in keeping with either modern armored warfare or Soviet doctrine describing the original informant as “a rank amateur on the question of armored vehicles”. With that said, it is worth noting the characteristics relayed to these German experts on this new and secret Soviet tank.
The first and most obvious sign that something appears to be wrong with the informant’s data on this Soviet tank is that the primary armament is given as being an ‘8.8 cm L/56 type gun’. This was a German gun, most famously in the form of the Kw.K. 36, as mounted on the German Tiger I. Although the experts stated that it was possible that the tank described could be improved with an L/70 version of that gun (as fitted to the Tiger II), this was still a German gun. In 1951, there is simply no reason to suppose that the Soviet army would need to use, reuse or produce their own clones of this WW2-era German gun for their own purposes.
The secondary armament is also unusual as it is described and shown as consisting of two machine guns; one firing forwards and another to the rear. Each is mounted in a ball-joint capable of 90 degrees of movement left and right.
The layout and shape of this tank are unusual and quite unlike any Soviet tank known to have existed at this time. The dimensions of the vehicle given by the informant are 7 m long, about 3 m wide and about 2 m high, with a weight of just 30-35 tonnes. The entire body is made from a giant curved structure with a single entrance hatch on top and with the gun in the front and center of the hull. There is no turret but, with the gun mounted towards the mid-point of the tank and with a machine gun at both ends, there is little room inside in which to squeeze the gun recoil, crew, and ammunition. At least five crew positions; commander (top left), front gunner (front left), driver (front right), loader (rear center), rear gunner (rear right) are provided for within the design, although there is no mention of a gunner for the primary weapon. An arrow on the sketch with the report indicating either the position of the engine or gunner is redacted. Unless the commander is also doubling-up as the gunner, a sixth crew member would be needed to operate the primary weapon. All of them, apart from the rear gunner, are provided with a forward facing vision slit for observations and the top positions for the commander and possible gunner have sideways facing observation slits. If indeed there were only five crew, as indicated by the informant, then there would be no crew member in the top right and there would be no need for a vision slit. The predominant feature of the design is the heavily curved body extending about half-way down the suspension of the vehicle. Where the body goes over the tracks this is described as an “armored” or “chain” apron (chain as in the tracks).
The engine is described as lying between the driver and rear gunner, which would place it approximately underneath the center of the vehicle with the commander, loader and gunner sat over it. The engine itself is rather implausibly listed as being a 600 hp petrol engine of US manufacture rather than of Soviet origin, although the make and type are not specified. The informant gave the top speed as 25 km/h, although the German experts reviewing the data from the informant suggested that an 800 hp engine could be substituted instead to provide up to 50 km/h for the tank.
Despite the shape of the Turtle tank indicating a cast body, the informant provided data that the body was of welded steel. The data provided for the armor gave a value of 80 mm for the front, 50 mm for the sides, 30 mm for the rear, and 20 mm for the floor. In light of that, the informant’s claim that even 105 mm and 180 mm shells had no effect on the armor was justifiably considered to be ‘nonsense’ by the German experts.
One further suggestion of note regarding the analysis of the armor was that the German experts considered it possible that the vehicle could use a protective coating 12.7 mm to 25 mm (½” to 1”) thick over the surface which would remove all the seams and make it invulnerable to limpet-type mines. This reference to limpet-type mines and protective coatings is an interesting reference to anti-magnetic coatings, the most famous of which is the German Zimmerit of WW2.
The informant seems to have suggested some new type of steel alloy was used for armor but this was discounted by the German experts on the basis that there were so many German scientists ‘honeycombed’ within Soviet industry post-war that such a development would have become known.
Nonetheless, the assessment was that the tank with this shape would benefit from being able to deflect armor-piercing and delayed-action high explosive shells fired at close range but parts would remain vulnerable to shells fired from an 8.8 cm L/56 or those with a shaped charge.
The Turtle Tank is not even a tank, it is instead clearly an assault gun with a fixed, forward-facing gun in a casemate. The Soviets made some very competent assault guns based upon the hulls of existing tanks like the T-34 or IS-series with a roughly similar arrangement, but nothing like this Turtle Tank. The date is 1951, so there are not a lot of possible candidates for what real vehicle the informant might have been referring to and this presupposes that the informant actually saw a real vehicle. If it is something genuine then perhaps the best candidate is something related to the ASU-85 assault gun which was in the early design phase at around this time but even so, the resemblance is terrible.
Perhaps it was/is some kind of top-secret Soviet assault gun which has been hitherto undiscovered by Soviet and Western tank historians, perhaps the informant was simply mistaken, or lying, or perhaps the experts were subject to a counter-intelligence ruse by the Soviets.
The German experts were unconvinced by this informant’s information. It was not that the vehicle was not possible, but that it was not plausible, with the experts stating that it would “constitute a complete departure from known Soviet policies”. The idea that this vehicle, so totally different from the Soviet assault guns of the day such as the SU-100 or ISU-152, has subsequently gone undiscovered is somehow unimaginable.
That said though, the German experts assessing the information from this informant seem to have agreed on the most likely outcome being the latter of the possible options, a counter-intelligence ruse. Namely, Soviet intelligence deliberately supplying false intelligence to a suspected informant or double agent, and, to back this up, they compared it to “similar methods used by the Nazi regime”, probably referring to the ‘Panzer X’.
Nevertheless, regardless of how or why this information got to the West, it was given a proper examination, by experts, and assessed to be implausible.
The informant’s claim that a pilot model of this vehicle was actually built, and demonstrated to the East German paramilitary police is also unlikely. Whilst a design which may never have left the scribblings of an engineer’s notebook might have gone unnoticed for nearly three-quarters of a century, the existence of such an unusual vehicle, with such unusual features, and departing as it does from Soviet experience, means that the Turtle tank can be fairly assessed to be a fake tank.
What it does do though is provide an excellent case in point as to the difficulties of gaining intelligence of the latest weapons from an adversary (in this case the US spying on the USSR) and the caution which should be exercised post-script in reviewing these historic documents.
Illustration of the ‘Turtle’ Tank produced by Jarosław Janas, funded by our Patreon campaign.
|Dimensions (L-W-H)||7 x ~3 x ~2 meters|
|Crew||6 (Commander, Gunner, Loader, Driver, Front Hull Machine Gunner, Rear Hull Machine Gunner)|
|Propulsion||600 hp American petrol engine (possible to fit an engine up to 800 hp)|
|Suspension||Independant torsion bar|
|Speed (road)||25 km/h (up to 50 km/h with 800 hp engine)|
|Armament||.8cm L/56 gun (possible to substitute 8.8 cm L/70) and two machine guns (1 forwards facing and 1 rearwards facing)|
|Armor||welded steel 80mm front, 50mm sides, 30mm rear, 20mm floor|
|Total production||7 prototypes|
CIA Report ‘German Experts’ Analysis of the Alleged Soviet ‘Turtle Tank’ dated 4th April 1951.