The Surprisingly Long and Determined Effort to Create a Literal Flying Tank

The Great War of 1914-1918 has been described as the first “industrial war”, and saw the battlefield debut of a number of advanced weapons, including the aeroplane, poison gas, the tank, the flamethrower, and the submarine. Of these, the tank and the aeroplane would go on to completely revolutionize modern warfare. The post-war years saw great leaps in the development of these technologies as designers sought to create weapons powerful enough to prevent another World War from ever breaking out. Some of these experiments, however, went in rather bizarre directions, and in a curious trend that would make Pimp My Ride’s Xzibit proud, several nations spent a considerable amount of time and effort trying to mash these two very different vehicles together and create a workable flying tank.

While aircraft served in many roles during the Great War, including aerial reconnaissance, ground attack, and air-to-air combat, it was not until after the war that they were seriously considered for transporting troops and equipment to the battlefield or dropping them behind enemy lines. The first nation to experiment with airborne forces was the Soviet Union, which conducted the first military parachute jumps on August 2, 1930 just outside Moscow. By 1941 the Soviet airborne forces had grown to ten brigade-sized corps, but aside from a handful of instances they never jumped into combat and were mostly used as elite ground troops. The first nation to actually use paratroops in combat was Nazi Germany, whose Fallschirmjager were used to great effect during the invasion of Denmark, France, and the Low Countries in the summer of 1940 – and for more on that, please check out our previous video How the Nazis Managed to Capture the World’s Strongest Fortress in Less Than 20 Minutes.

As effective as they were, however, paratroopers suffered from a fundamental weakness. As all their equipment had to be delivered by parachute, airborne troops were perpetually short on ammunition and could not be supplied with vehicles or heavy weapons. This placed them at a significant disadvantage against regular troops – especially those equipped with heavy vehicles like tanks. Parachute drops  also tended to scatter paratroops over a wide area, forcing them to waste time regrouping and gathering their equipment before launching an attack. The Germans partially addressed this problem through the use of troop-carrying gliders, which could land a full squad of men and their equipment directly onto the target with pinpoint accuracy. However, early gliders like the DFS 230 were nowhere near large enough to carry even a light utility vehicle – much less a tank – into combat.

As with the general concept of airborne forces, it was once again the Soviets who first developed methods for airlifting tanks into combat. In the early 1930s, the Soviets experimented with strapping light armoured vehicles like the T-27 and T-37 tankette beneath Tupolev TB-3 heavy bombers. The original intention was for the aircraft to land and lower the tank and its crew to the ground. However, as this required a large, flat landing area and made the aircraft vulnerable to enemy fire, the Soviets switched instead to the extraordinary technique of dropping tanks from aircraft while skimming only a few metres above the ground. Several tanks are reported to have been dropped in this manner during the 1940 Soviet invasion of Bessarabia in what is now Moldova and Ukraine. It is not recorded, however, whether their crews survived the ordeal without massive concussions.

Whatever the case, these methods were soon deemed inadequate, and the Red Army turned to famed aircraft designer Oleg Antonov to develop an assault glider large enough to carry a tank into combat. Antonov, thinking outside the box, instead decided to convert the tank itself into a glider by fitting it with a pair of massive wooden biplane wings and a twin-boom tail. This Frankenstein’s monster of a vehicle, dubbed the Antonov A-40 or KT – short for Krylya Tanka or “winged tank” – was designed to be towed into the air by a heavy bomber like a Petlyakov Pe-8 or Tupolev TB-3 and released near its target. The crew would then pilot the combination to the ground, spinning up the tracks at the last minute in order to make a running landing. The wings and tail would then be cut away, allowing the tank to trundle into action. Control while gliding was accomplished by connecting the tank’s gun to the control surfaces, such that raising and lowering the gun caused the aircraft to pitch up and down and rotating the turret caused it to roll side-to-side. To prove the concept, Antonov modified a T-60 light tank by removing its gun, headlights, ammunition, and much of its fuel, and arranged for it to be test-flown by famous glider pilot Sergei Anokhin. The first and only test flight of the A-40 took place on September 2, 1942, and very nearly ended in disaster. While the winged tank successfully rose into the air, it was so heavy and produced so much drag that the bomber towing it came close to stalling and was forced to cut the glider loose shortly after takeoff. Incredibly, Anokhin skilfully managed to land the vehicle, detach the wings, and drive the tank back to the airfield. However, due to a lack of official support and aircraft powerful enough to safely tow the A-40, the project was soon cancelled.

One possible solution to the Soviets’ problem would have been to make the A-40 self-propelled, and indeed this concept was briefly tinkered with a decade prior by American inventor John Walter Christie. In 1928 Christie developed the Christie Suspension System used in a number of WWII tanks including the British Crusader and Soviet T-34. This system allowed tanks to attain previously unheard-of speeds over rough terrain and to continue driving even if the tracks had been blown off. In 1932, Christie turned his considerable creative talents to the development of a flying tank that would allow armoured divisions to be quickly deployed behind enemy lines. A scaled-down version of his M1928 tank design, the flying tank would weigh only 4 tons, sport a powerful 75mm gun, and be able to drive 70 mph across rough terrain and 100 mph on prepared roads. Like the Soviet A-40, the tank would be fitted with a massive set of breakaway wings, this time featuring a propeller geared to the tank’s own engine. Christie’s intention was for the tank to accelerate across the ground using its tracks until it reached 70 mph, whereupon power would be transferred to the propeller, allowing the vehicle to lift off. As Christie boasted in an interview in Modern Mechanics magazine:

“What is more, the pilot of the flying tank does not need the level ground required by a bombing plane to take off. He can take off through mud, though bumpy ground and ground which would prevent the average plane from rising.”

Like many weapons designers of the era, Christie saw great potential in his invention as a deterrent to future conflict, stating in the same interview:

“The flying tank is a machine to end war. Knowledge of its existence and possession will be a greater guarantee of peace than all the treaties that human ingenuity can concoct. A flock of flying tanks see loose on an enemy and any war is brought to an abrupt finish.”

Alas, Christie’s prediction would not come true, and his flying tank concept never left the drawing board. Nor did flying tanks become a fixture of the Second World War battlefield, though this was not for lack of trying. Among the other nations to experiment with airlifting tanks was Japan, which in 1943 developed the Special No.3 Flying Tank or So-Ra, a 3-ton vehicle designed to be flown into combat aboard the Kokusai Ku-7 “Buzzard” assault glider. However, by the time the prototype was completed, Japan’s strategic situation had severely deteriorated and the tank never entered production. Nazi Germany, the original pioneer of airborne operations, also experimented with tank-carrying gliders, though rather than building a specialized airborne tank, German designers instead chose to design gliders around existing tank models. In anticipation of Operation Barbarossa, the Nazi invasion of the Soviet Union, in 1940 the Luftwaffe’s Technical Bureau put out a tender for a heavy-lift assault glider capable of carrying 200 fully equipped troops, an 88mm antitank gun and its towing tractor, or a Panzer IV medium tank. Two aircraft companies, Messerschmitt and Junkers, submitted designs for trials. The Junkers entry was the Ju 322 Mammut, a massive and bizarre aircraft built mostly of wood and featuring a wingspan of 62 metres and a large central cargo bay with a hinged ramp for loading and unloading cargo. The Mammut made its first flight in April 1941 but proved dangerously unstable and difficult to control both under tow and in free flight, nearly resulting in the loss of the glider and towplane. Furthermore, during ground tests a tank crashed through the cargo bay floor. The Luftwaffe quickly deemed the design inadequate and the project was cancelled in May 1940.  

Messerschmitt’s entry, the Me 321 Gigant, was only slightly more successful. Built of fabric-covered aluminium tubing, the Gigant had a wingspan of 55 metres and featured large clamshell doors in its nose for loading and unloading cargo – a standard feature on many transport aircraft today. Like the Mammut, however, the Gigant’s sheer size made it difficult and dangerous to operate. The massive control surfaces were operated via cables with no hydraulic or other assistance, making the controls extremely heavy and quickly exhausting the pilot. There were also few aircraft in Germany capable of towing a fully-loaded Gigant into the air. During the glider’s first test flight on February 25, 1941, the towing aircraft, a four-engine Junkers Ju 90 transport, struggled to get the Gigant airborne and was forced to cut loose early to avoid stalling. The Germans attempted to correct this issue by fitting the Gigant with eight detachable liquid-fuelled rocket pods to provide extra thrust at takeoff – a technique today known as Rocket-Assisted Takeoff or RATO. They also developed a special towing aircraft known as the Heinkel He 111Z Zwilling or “Twin,” essentially two regular Heinkel He 111 bombers spliced together with an extra engine added. However, development of the Zwilling proceeded slowly, and the Germans were forced to tow the Gigant using an arrangement of three Messerschmitt Bf-110 heavy fighters known as a troika-schlepp. This method required considerable coordination between the three towing aircraft and proved highly dangerous, with one test flight in 1941 ending with two Bf 110s accidentally colliding. The ensuing crash  resulted in the deaths of all 9 men aboard the three towing aircraft and the 120 troops aboard the glider. This incident would remain the single deadliest aviation accident in history until the New York mid-air collision of December 16, 1960.

Despite its flaws, the Gigant entered service in May 1941 and was used to transport supplies to German troops advancing into Russia. Opinion on the Gigant’s performance was mixed. While the glider could carry far more cargo than regular transport aircraft, the troika-schlepp towing arrangement severely limited its operational range, while the primitive conditions on the Russian Front meant that once a Gigant landed, it could not be used again. Messerschmitt soon realized that the Gigant would be far more useful as a self-propelled aircraft, and began work on a powered version called Me 323. To avoid further straining Germany’s already thinly-stretched engine industry, the aircraft was fitted with six Gnome-Rhone engines captured from the French. The Me 323, the largest land-based transport to fly during WWII, entered service in September 1942, carrying desperately needed supplies to General Erwin Rommel’s beleaguered Afrika Korps in Tunisia. They were also used extensively during the Italian Campaign. While useful, the lumbering Gigant unfortunately proved easy prey for Allied fighter aircraft, and suffered heavy losses wherever it was deployed.

Ultimately, the only belligerent nation to deploy airborne tanks in the assault role was Great Britain. In response to the stunning successes of the German Fallschirmjager in France and the Low Countries, in June 1940 Prime Minister Winston Churchill ordered the creation of Britain’s own airborne forces. In order to provide the paratroopers with armour support, in 1941 the War Office decided to equip the Airborne divisions with the Mk. VII Tetrarch light tank. While not originally designed as an airborne tank, at only 8 tons the Tetrarch was the smallest and lightest armoured vehicle in the British arsenal. Light tanks had also performed poorly during the Battle of France, causing the Tetrarch to be declared obsolete. Large numbers were thus readily available for use by the airborne forces. To carry the Tetrarch into combat, the War Office selected the General Aviation GAL. 49 Hamilcar assault glider. Due to delays in the Hamilcar’s development, it was not until January 1944 that the Glider Pilot Regiment finally began training exercises with the Tetrarch. These exercises were highly successful, with the Regiment making over 2,800 experimental landings with only three fatal accidents. The Tetrarch-Hamilcar combination was approved just in time to participate in Operation Tonga, the British airborne component of the D-Day landings on June 6, 1944. Twenty Tetrarchs were landed behind enemy lines in support of the assault on the French city of Caen, but their performance was less than impressive. On the flight to Normandy, one Tetrarch came loose and broke through the nose of its glider, sending it and its crew plummeting into the English Channel below. Two further Tetrarchs were destroyed when the gliders carrying them collided on landing, while a fourth was hit by a landing glider while being unloaded, flipping it over and rendering it unusable. This comedy of errors continued as the remaining tanks’ tracks became fouled in parachute rigging lines, causing all but two to become immobilized.

The two surviving Tetrarchs fared little better than their compatriots. One of the Tetrarch’s greatest flaws was its small size, which limited its crew to three: a driver, a loader, and a Commander/gunner. The dual responsibility of commanding the tank and operating gun quickly overtaxed the Commander, making the Tetrarch difficult to operate effectively in the field. It was also thinly armoured and lightly armed with an obsolete 2-pounder gun. In Normandy, the Tetrarchs found themselves completely outmatched by even the lightest German tanks, and most were quickly destroyed in combat. Yet despite their poor combat performance, in a strange twist of history the Tetrarchs still managed to have a major impact on the Battle of Normandy. On the morning of June 6th, 1944, the 21st Panzer Division was on its way from Caen to the Normandy beaches to counter the Allied amphibious landings. Upon learning that British tanks had been airdropped behind them, however, the German commander decided to halt his advance and retreat back to Caen.

In response to the Tetrarch’s known flaws, shortly after its adoption in 1941 the British War Ministry put out a request for a light tank specifically designed for the airborne role. As the British tank industry was already stretched to capacity, the request was passed on to the United States War Office. The result was the M22 tank, designed by the Marmon-Herrington Company of Louisville, Kentucky. Weighing only 7 tons, like the Tetrarch the M22 had a crew of three and was armed with one 37mm gun and a .50 caliber machine gun in the turret and two more .50 caliber guns in the hull. Though light and compact enough to be carried aboard a Hamilcar glider, the M22 was originally designed to be transported into combat by a Douglas C-54 Skymaster transport aircraft. Four heavy brackets on the hull allowed the tank to be bolted under the aircraft’s belly, while the turret was designed to be removed and stored aboard the aircraft along with the tank’s crew. Upon landing, a well-trained crew could detach, reassemble, and get the tank combat-ready in about 10 minutes. However, this transport method required the use of a prepared runway, and was never used in combat. Following further development, including the deletion of the gun stabilization system and the hull machine guns to save weight, the first M22s were delivered to the 6th Airborne Armoured Reconnaissance Regiment in late 1943. Strangely, despite a War Ministry directive requiring that American-built tanks be named after Civil War generals like Grant, Lee, and Sherman, in British Service the M22 was known as the “Locust.”

British trials of the Locust revealed various mechanical issues, which were not corrected in time for the tank to participate in the Normandy Landings. Following the Tetrarch’s poor performance during Operation Tonga, however, the type was retired and completely replaced by the Locust. The Locust’s combat debut came on March 24, 1945 during Operation Varsity, part of the Allied crossing of the Rhine River into Germany. Eight Locusts of the 6th Airborne Division reserve were landed by Hamilcar glider to support infantry operations on the far riverbank. As with the Tetrarchs in Normandy, however, these landings were a debacle, with one Locust falling out of a disintegrating glider and another being completely destroyed when its glider crashed through a farmhouse. Of the remaining six tanks, only two emerged from the landings undamaged and with uninjured crews. Nonetheless, the Locusts fought surprisingly well in the ensuing battle, with one being destroyed in a duel with a German Panther tank and another being immobilized but managing to hold its ground and inflict over 100 German casualties. By the following day, however, the front line had stabilized and more capable tanks became available, and the Locusts were pulled back to defensive positions and eventually withdrawn from combat altogether. Operation Varsity would be the only time the Locust would see combat during WWII, the type being declared obsolete soon after. After the war remaining stocks of Locusts were sold off to foreign militaries including those of Belgium and Egypt, with the latter seeing extensive service during the 1948 Arab-Israeli war.

In the end, the flying tank turned out to be a technological dead end. The features required of an effective infantry support tank – such as thick armour and heavy armament – were simply incompatible with the capabilities of 1940s aircraft. It would not be until the late 1960s that a practical airborne armoured vehicle would be developed by – you guessed it – the Soviet Union. Introduced in 1969 and still used today, the BMD-1 is a small amphibious Infantry Fighting Vehicle designed to carry 2 crew and 6 soldiers into combat. Built of lightweight aluminium alloy and weighing only 8 tons, the vehicle can be carried by a variety of Russian heavy-lift helicopters or air-dropped from a transport aircraft using a special parachute rig. Originally it was intended that the vehicle and crew would be dropped separately, but this proved problematic as the crew often landed some distance from their vehicle. However, even with parachutes the BMD landed too heavily to be safely dropped with its crew aboard. This problem was eventually solved using solid-fuel retrorockets to slow the vehicle down just before landing – a technique also used with Russian Soyuz space capsules. BMD crews also sit in specially padded seats to cushion the shock of landing. This prominent exception aside, however, the term “flying tank” is perhaps best applied not to a literal tank but to a variety of Russian ground attack aircraft like the WWII-era Ilyushin IL-2 Sturmovik and the later Mil Mi-24 Hind attack helicopter, whose heavy armour and armament make them legendarily indestructible.

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