Gap Jumping Tanks?

Just when you think you've seen it all ... .

Gap Jumping Tank: Weird experiments with rockets late in the war to propel a Valentine tank across obstacles such as minefields , AT-ditches, trenches, dragoon-teeths, etc.


Artists impression of the jumping Valentine


The Valentine chassis was fitted with 26 rockets, 13 on each side in four containers... Incredible, but true... and, obviously it didn't work.

Jumping Universal carrier fitted with 6 rockets (3 rockets on each side). Note the covers or flaps on the bottom of the Universal Carrier meant to shield the tracks from the blast, to prevent them from being damaged from the heat.


Before and after the test ...

Courtesy Panzerserra Bunker- Military Scale Models in 1/35 scale: Valentine Mk II Canal Defense Light (CDL); Tank, Infantry, Mk III - case report

 

I think that artist's impression is VERY fanciful.

 

Trials resulted in the vehicle always arriving upside down. The reason for this was not understood and the project abandoned. Later analysis revealed that the rocket exhaust was scooping out a particularly shaped bowl that directed a blast back up under the vehicle that flipped it over

 

Hot air almost always produces unintended and unpleasant consequences.

 

Part of another old piece of mine
In wartime Britain inventors of the Department for Miscellaneous Weapons Development (DMWD sometimes known as The Wheezers and Dodgers) reasoned that if one could let a load fall free from an aircraft and only slow it down just before it crashed into the ground there would be less chance of it being hit by gunfire on the way down. Moreover it would be easier to drop it on a precise target as there would no longer be the problem of wind drift that a parachute experiences. The Wheezers and Dodgers had a record of many major contributions to Britain’s war effort (including floating track ways to allow faster unloading from the Mulberry Harbour off the Normandy beachhead). However they seem to have had an almost unquestioning faith in the utility and reliability of rockets and produced many devices dependent upon their use. They devised a delivery system called Hajile (a reversed Elijah), in which the cargo (such as a Jeep) was lashed to a pallet to which powerful solid fuel rockets had been fixed. A weight on a rope hanging beneath the pallet would hit the ground first and trigger the rockets which would slow the falling load so that it touched down gently. Initial trials over water showed that the rockets did indeed slow the pallet down to a near stop just before it hit the water (and sank).
Trials over land had less success, on some occasions the rockets failed to fire and Hajile buried itself in the ground whilst on other occasions they were not powerful enough so that a very hard landing resulted. The system was very susceptible to the timing of individual rockets firing and burning out, the pallet could easily become destabilised. In one trial he pallet and its load could be seen falling towards the ground when, just before impact, the rockets fired. Amid smoke and flames the falling object slowed and came to a halt. But the rockets were still firing and so it began to rise again back into the air. When it gained some height the rockets on one side of the pallet ran out of fuel and stopped. The remaining rockets were still blazing away and the pallet became unbalanced and flipped over so that it started back down again down impelled by both gravity and the power of the rockets that still remained firing. It hit the ground with considerable force and disintegrated. After some effort the rocket firing became more reliable but the pallet still flipped over on landing. It took considerable research to discover that the problem lay in the fact that the very powerful rockets were blasting out a bowl shaped cavity immediately below the Hajile. This bowl reflected back the rocket blast into the bottom of the pallet flipping it over. The problem had still not been solved until after the D Day landings and the big Hamilcars glider had entered service by which time it was considered that Hajile would not be needed and the project came to a halt.


Another body that had great faith in rockets was the Specialised Armour Development Establishment (SADE) formed in 1945, after the war ended, to carry on some of the work of the 79th Armoured Division.
The 79th developed and used a number of rocket based devices and their successor SADE followed suite. One such device developed by SADE was a rocket harness for assisted emergence from steep unstable beaches and to enable bogged down tanks to get out of mud holes. Each side of the vehicle had eight rockets fitted and these proved successful in every trial. A logical progression from this would be to use rockets to enable a tank to avoid obstacles altogether by taking to the air and leaping over them. Rockets could launch the vehicle and, presumably, cushion its landing. A Universal carrier and a Valentine tank (both unmanned) were used for trials. There was no problem in getting the vehicle airborne. The rockets fired every time and the vehicle rose hidden in a cloud of fire and flame (a sort of Elijah’s chariot) and when this cleared it was on the other side of the obstacle – upside down! This happened every time no matter what kind of stabilising devices were tried. The smoke made it impossible to see what was taking place in flight and the problem was never rectified. The leaping tank project was abandoned. It nows seems likely that it was the same problem of a backblast when landing.

 

Possibly an earlier jumping tank
If you couldn’t fit the vehicle into an aircraft, thought some military inventors, why not fit wings to the vehicle? The 1930s had already seen ingenious (but on the whole unsuccessful) attempts to produce the flying automobile. It was left to the indefatigable Mr. Christie to introduce the flying tank. He took his 1938 fast tank (the one capable of 70 mph across country) and added wings, a tail and a propeller.
There appears to be some doubt as to exactly why Christie produced this hybrid. Some sources suggest that it was to create a tank that could ‘hop’ over obstacles on the battlefield, if so the idea, whilst superficially seductive, is ludicrous. The tank would have to wear its wings until it encountered such an obstruction, these would make it a large and unwieldy ground vehicle much more likely to encounter obstacles it would need to fly over (if it could find room for takeoff), the solution would tend to create the problem it was intended to resolve. Moreover ‘hopping’ over an obstacle without knowing if there was anywhere suitable to land on the other side would seem somewhat foolhardy. The tank would probably only be practical in areas that were relatively large, open and flat with few obstacles (which would remove the raison d’etre for it in the first place). The second theory advanced is that it was intended to be carried under an aircraft and released to land behind enemy lines. This makes more sense until one considers that the USA at the time had neither airborne forces nor military aircraft capable of either lifting or towing Christie’s flying tank. Of course by this time Christie seems to have been so focused on the idea of speed in tanks for speed’s sake that one should not assume that there was any other logical purpose behind the vehicle and Christie having produced a solution may have been looking for a problem that it fitted. There is no evidence that the thing ever flew.

 

The only rotorcraft development work carried out in the UK during WW2 was by a small team of engineers at the Airborne Forces Experimental Establishment, first at RAF Ringway and then at Sherburn in Elmet. The team (it was mostly the staff of a pre-war company) was led by Austrian born Raoul Hafner and the first design was the Rotachute a one-man gyro glider. Hafner carried out the early concept/design work whilst interned as an Enemy Alien for 5 months during 1940. The Rotachute was successful in trials but no use could be found for it, but the concept could be used for something larger. Hafner suggested that his Rotaplane could be used on a lifeboat, submarine or a tank. To this end he wrote a report and used the Valentine tank as an example to get approval for his concept. The authorities were interested but couldn't afford the tank so they gave him a Jeep to work with. He got the Jeep to fly as the Rotabuggy but the vibrations from the rotor above 60 knots were such that the project was dropped, it had missed D-day anyway.
This is the drawing from the Rotatank proposal report.

 

Does anyone know anything about the Soviet G-45 ? This is as much as I know.

Dropping men and materiel by parachute has a number of drawbacks. If done in daylight the parachutes are visible from over a wide area and may be fired upon, it is impossible to conceal the actual landing point and wind and other climatic factors can cause the intended drop zone to be missed altogether. These are likely to cause problems in any operation but are particularly likely to be fatal to any attempts at surprise or secrecy. Dropping at night reduces some of these risks but greatly increases the chance of scatter and of missing the drop zone completely.


One radical solution is to dispense with the parachute. The Soviets experimented with this in the 1930s, not for any of the reasons described above but because the USSR was finding silk expensive! A device called the G-45 was devised. Intended to carry up to a dozen men it was intended to be dropped at low altitude from a bomber and be able to touch down on land or water, in the later case it would plane on the water before coming to a halt. To cushion landing on solid ground it was equipped with wire spoked wheels on very large springs. One of the unmanned prototypes broke up on impact with water and so the Soviet Special Design Bureau, as a caring employer, had the designer and his assistant strapped into the device and dropped over land. By the time of their release from hospital the project had been scrapped.

 

SDTD Monthly Liaison Letter No.3 - April 1946

 

https://www.warhistoryonline.com/history/flying-tank.html

On September 2, 1942 the first flight of the “tank wings” occurred. Sergey Anokhin, the famous test pilot, glider pilot, and Hero of the Soviet Union whom friends called “the commander of a flying turtle,” piloted the A-40.
In spite of the absence of a turret and a lighter weight, the tank’s large mass limited the TB-3’s speed to 80 mph. That was too slow, and the A-40 reached a height of only 131 feet. The TB-3’s engines began to overheat, so it was decided to land at an airfield near Bykovo.

Sergey Anokhin, thanks to his professionalism, managed to successfully land the tank. After landing, he engaged the tank’s motor and, without shedding its wings, slowly drove the tank to the command post of the airfield.
Seeing this unusual vehicle, the head of the airfield raised an alarm and ordered that the anti-aircraft battery be prepared. Anokhin was forced to stop the tank and get out, and he was immediately detained by soldiers of the Red Army.
After the arrival of the flight test institute’s rescue team, the incident was settled. Anokhin was released, and the tank was returned.

Sergei Anokhin (test pilot) - Wikipedia

Bykovo Airport - Wikipedia

See also - Quiz Number Six

 

Somewhat relatedly, the US looked into a jumping armored car in World War II. The National Defense Research Committee in spring 1941 initiated projects on a series of armored cars featuring a suspension that could squat and then release the stored energy, jumping the vehicle over obstacles. No actual cars were manufactured, but a one-wheel test rig built by the Baker Manufacturing Co. indicated the machine could clear a 49" vertical obstacle or a 49-foot ditch if it was traveling at 40 mph. In typical understatement, Hunnicutt opined that "...under estimating the dimensions of the obstacle might have been disastrous."