M22 Locust The Light Tank ( Airborne ) M22 or Locust was an American - designed airmobile light tank which was produced during World War II . The Locust began development in 1941 after the British War Office requested that the American government design a purpose - built airborne light tank which could be transported by glider into battle to support British airborne forces . The War Office had originally selected the Light Tank Mark VII Tetrarch light tank for use by the airborne forces , but it had not been designed with that exact purpose in mind so the War Office believed that a purpose - built tank would be required to replace it . The United States Ordnance Department was asked to produce this replacement , which in turn selected Marmon - Herrington to design and build a prototype airborne tank in May 1941 . The prototype was designated the Light Tank T9 ( Airborne ) , and was designed so that it could be transported underneath a Douglas C - 54 Skymaster transport aircraft , although its dimensions also allowed it to fit inside a General Aircraft Hamilcar glider . After a series of modifications were made to the initial prototype , production of the T9 began in April 1943 . It was significantly delayed , however , when several faults were found with the tank ' s design . Marmon - Herrington only began to produce significant numbers of the T9 in late 1943 and early 1944 , and by then the design was considered to be obsolete ; only 830 were built by the time production ended in February 1945 . As a result , the Ordnance Department gave the tank the specification number M22 but no combat units were equipped with it . However , the War Office believed that the tank would perform adequately despite its faults , so the tank was given the title of ' Locust ' and 260 were shipped to Great Britain under the Lend - Lease Act . Seventeen Locusts were received by the 6th Airborne Armoured Reconnaissance Regiment in late 1943 , but mechanical problems led to the tanks being withdrawn in favour of the Tetrarchs previously used by the regiment . In October 1944 however , the remaining Tetrarchs of the regiment were replaced by Locusts and eight were used during Operation Varsity in March 1945 . The tanks did not perform well in action ; several were damaged during the landing process and one was knocked out by a German self - propelled gun . Only two Locusts were able to reach their planned rendezvous point and go into action , occupying a piece of high ground along with an infantry company . The tanks were forced to withdraw from the position after several hours however , because they attracted artillery fire that caused the infantry to suffer heavy casualties . The Locust never saw active service with the British Army again and was classified as obsolete in 1946 . A number of Locusts were used by foreign militaries in the post - war period however ; the Belgian Army used Locusts as command tanks for their M4 Sherman tank regiments , and the Egyptian Army used several company - sized units of Locusts during the 1948 Arab – Israeli War . Development history . Background . The Light Tank ( Airborne ) M22 , also known as the Locust , began development in late 1941 in response to a request by the British military earlier in the year for an airmobile light tank which could be transported onto a battlefield by glider . At the time the request was made , the War Office considered using the equipment in Britain ' s fledgling airborne forces , which had been formed in June 1940 by order of the Prime Minister , Winston Churchill . When officials at the War Office examined the equipment that would be required for a British airborne division , they decided that gliders would be an integral component of such a force . These gliders would be used to transport troops and heavy equipment , which by 1941 was to include artillery and some form of tank . Plans to transport an airborne tank went through a number of revisions , but by May 1941 it was considered feasible for a tank weighing to be carried for to in a glider , although the latter would have to be specifically designed for the task . In a conference held on January 16 , 1941 , it was decided that the General Aircraft Hamilcar , under development at the time , would be used to transport a single tank or two Universal Carriers . A decision had recently been made by the War Office that light tanks were no longer to be generally used in the British Army ; on the whole they had performed poorly during the Battle of France and were considered to be a liability . As a result the Vickers - Armstrong Light Tank Mk VII Tetrarch light tank was now considered obsolete . This made it available for use by the airborne forces and it was chosen by the War Office as the tank to be transported by glider . However , it had not been designed specifically as an airborne tank or to be airmobile , and it also possessed several faults . Its size limited the possible crew to three — a driver in the hull and a gunner and commander in the turret — which was found to be too few crew members to effectively operate the Tetrarch effectively . The gunner or commander , in addition to their own duties , had to act as loader for the 2 - pounder , which caused delays in combat ; a report on the tank written in January 1941 stated that since the commander had to both fight and control the tank , controlling a troop of Tetrarchs during combat would be almost impossible . The War Office was also aware that the tank had a faulty cooling system that made the Tetrarch unsuitable for service in hotter climates , such as the Middle East and North Africa . A purpose - built airborne light tank was therefore required to replace the Tetrarch , but the decision was taken by the War Office not to produce the tank in Britain due to a lack of production capacity . Instead the American government was approached with a request that it produce a replacement for the Tetrarch . This request was made by the British Air Commission in Washington , D . C . , with a proposal calling for a tank of between and to be developed , this being the maximum weight the War Office had decided could be carried by current glider technology . The proposed tank was to have a primary armament of a main gun and secondary armament of a . 30 - 06 Browning M1919A4 , and a crew of three . The specification also called for a maximum speed of and an operational radius of . The turret and front of the hull were to have an armour thickness of between and , and the sides of the tank a thickness of . The United States Ordnance Department was given the task of developing the proposed tank , and in turn requested designs from three American companies : General Motors , J . Walter Christie and Marmon - Herrington . The design offered by Christie in mid - 1941 was rejected as it failed to meet the specified size requirements , as was a modified design the company produced in November . At a conference in May 1941 , the Ordnance Department chose the Marmon - Herrington design and requested that the company produce a prototype tank , which was completed in late 1941 ; it was designated the Light Tank T9 ( Airborne ) by the company and the Ordnance Department . Development . The T9 had a crew of three and weighed . It was armed with a main gun and a coaxial . 30 - 06 Browning M1919A4 machine - gun , as well as two further machine - guns on the right - hand side of the bow . The main gun and coaxial machine - gun were mounted in a powered turret , which also had a gun stabilizer installed to allow the gun to be fired when the tank was moving . The T9 was powered by a 162 horse - power six - cylinder , air - cooled Lycoming engine , and the thickness of the armour varied ; the front , rear and sides of the hull had a thickness of while the sloped portions of the hull had a thickness of . The tank ' s engine was able to give it a maximum speed of . The T9 was not primarily designed to be transported by glider , a significant change from the original request , but instead was to be carried under the belly of a Douglas C - 54 Skymaster transport aircraft , using four lifting brackets welded onto each side of the hull of the tank . The turret was designed to be removable so that it could be detached and transported inside the C - 54 and reattached once on the battlefield . However , the T9 was of the correct shape , weight and size to be carried inside a Hamilcar glider , suggesting that these dimensions had been chosen deliberately so that the tank could be transported inside a glider if required . A number of changes were made to the prototype during testing . The main change was the addition of supporting steel beams to improve and strengthen the suspension of the tank , which increased the weight to , the maximum weight that could be carried by a Hamilcar glider . Two new prototypes were ordered by the Ordnance Department in January 1942 and were delivered by Marmon - Herrington in November 1942 . They were both designated T9E1 . The new tanks incorporated a number of requested changes . The turret was altered in shape ; it was lightened by the removal of the power traverse mechanism and the gyro stabilizer for the main armament . The front of the hull was altered from a stepped appearance to a more sloped profile , which would provide for a better ballistic shape ; the two . 30 - 06 machine - guns were removed from the bow of the tank and the suspension was altered to try and reduce the weight of the design . However , contrary to normal practice , the Ordnance Department had placed an order for the original T9 design in April 1942 , before the T9E1 models were delivered in November 1942 ; 500 were ordered in April and this order rapidly increased to a total of 1900 , with deliveries to begin in November . However , production difficulties and design changes caused this date to be delayed several times , and it was not until April 1943 that production on the T9 actually began . Production of the T9 peaked at 100 tanks produced per month between August 1943 and January 1944 ; however , this number rapidly declined when the results of the British and American testing programmes were reported to the Ordnance Department , and only 830 T9s were ever produced . The faults discovered with the design led to the Ordnance Department giving it the specification number M22 , but classing it as ' limited standard ' . No American combat units were equipped with the tank , although some of those produced were used for training purposes and two experimental units were formed and equipped with Locusts . The 151st Airborne Tank Company was formed on 15 August 1943 , despite concerns that there would be insufficient transport aircraft to deliver the unit into battle , and the 28th Airborne Tank Battalion was also formed in December of the same year . However , neither unit saw combat , due to the US Army ' s lack of interest in using them in an airborne capacity . The 151st Airborne Tank Company remained in the United States , shuttling from base to base throughout the war , and the 28th Airborne Tank Battalion was refitted with conventional tanks in October 1944 . Some 25 Locusts were ordered in April 1944 for use in the European Theater of Operations , and delivered by September ; although a small number were sent to the United States Sixth Army Group in Alsace , France , for testing , they were never used in combat . However , the British still required the M22 as a replacement for the Tetrarch and the first prototype Locust was shipped to Britain in May 1942 for testing , followed by the second prototype T9E1 in July 1943 . Although they were of the opinion that the M22 possessed a number of faults , the War Office believed it would perform adequately as an airborne tank . Thus the tank received the official title of " Locust " and 260 were shipped to Britain under the Lend - Lease Act . The majority of the Locusts ended up placed in tank parks until they were scrapped at the end of the conflict , and only eight ever saw action with British airborne forces . Faults . Extensive testing of the M22 occurred in 1943 and 1944 , and was conducted by both the Ordnance Department and the British Armoured Fighting Vehicle School at Lulworth . These tests uncovered a number of faults and problems with the Locust . The AFV School noted that the process of loading the M22 into a C - 54 transport aircraft took considerable time and involved the use of complex equipment . Overall the process took six untrained men 24 minutes , although it was believed this could be shortened with sufficient training . Unloading was also a long process , taking approximately ten minutes ; it was noted that the time it took to unload the M22 from a C - 54 on the battlefield meant that both the tank and aircraft would make excellent targets for enemy fire . Operational use of the tank would therefore be restricted to the availability of airfields large enough to accommodate a fully - laden C - 54 , which might not be in the right geographical location or might even have to be captured in advance of a planned airborne operation . A heavy transport aircraft , the Fairchild C - 82 Packet , was developed to specifically carry the M22 inside its fuselage and unload it through a set of clam - shell doors , but it did not enter service until after the war had ended . The US Army Armored Board released a critical report on the Locust in September 1943 , stating that it was inadequate in the areas of reliability and durability , and indicating that it would not be able to be successfully used during airborne operations . By 1944 it was also realized that the design of the tank was actually obsolete . The armor of the M22 in several areas was found to be so thin that it was incapable of even resisting the armor - piercing ammunition of a . 50 caliber machine - gun . Complaints were also made about the 37mm main armament , which was not powerful enough to penetrate the armor of most tanks used by the Axis powers . Similarly a report made on March 13 , 1944 by elements of the 6th Airborne Armoured Reconnaissance Regiment complained that when a high - explosive shell was fired from the gun , the resulting shell - burst was so weak that observers had difficulty in seeing where it impacted . There were also mechanical problems with the design , which caused it to be unreliable ; the engine was also found to be underpowered , possibly due to problems with the torque characteristics of the engine or an inefficient transmission system . Operational history . World War II . Initial service . By late 1941 , several new British units had been raised specifically trained to conduct airborne operations . The largest such unit was the newly formed 1st Airborne Division , and on 19 January 1942 the War Office took the decision that a light tank detachment would be amongst the support units attached to the division . Designated the Light Tank Squadron , this unit was to be formed of nineteen light tanks and would operate to the fore of the division , using their speed to capture objectives and hold them until relieved by other units . The unit chosen for conversion into the Light Tank Squadron was ' C ' Special Services Squadron , which had seen service as an independent tank unit during Operation Ironclad , the invasion of Madagascar in mid - 1942 . The squadron was also equipped with Tetrarchs , which had recently been re - designated as an airborne tank by the War Office . ' C ' Squadron was officially transferred to the 1st Airborne Division on 24 June 1942 , bringing with it seven Tetrarchs amongst the other vehicles it was equipped with . The unit immediately began training , but did not stay attached to the 1st Airborne Division for very long ; during mid - 1943 , the division was transported to the Middle East , where it would eventually participate in Operation Husky , the Allied invasion of the island of Sicily . ' C ' Squadron remained in Britain however , as not enough Hamilcar gliders had yet been built to transport and deploy all of their Tetrarchs . The squadron was transferred to the division with which it would spend the rest of the war ; the 6th Airborne Division , raised in April 1943 . The squadron continued to train as an air - portable unit and participated in a number of exercises intended to familiarize it with the duties it would perform , including reconnaissance of enemy positions and performing counter - attacks against enemy infantry and armor . In mid - July an American pilot was sent to Britain to illustrate that the tank could fit inside a Hamilcar and be landed , and then on October 25 the Light Tank Squadron received a shipment of seventeen Locusts . During November the new tanks were issued to the squadron , replacing a majority of the Tetrarchs ; however a small number of Tetrarchs fitted with a 3 inch ( 76 . 2 mm ) infantry support howitzer , which were designated as Tetrarch 1 CS ( Close Support ) , were retained . Several of the Locusts also were fitted with Littlejohn adaptor s to increase the range and penetration power of their main armament , although it is not clear how many were fitted or if they were fitted at manufacture or after they reached the squadron . The squadron was expanded into the 6th Airborne Armoured Reconnaissance Regiment in December 1943 , and as late as March 1944 , plans were made for the regiment to be equipped with seventeen Locusts and three Tetrarchs when it took part in Operation Tonga , the British airborne landings in Normandy . However , records indicate that by April the Hamilcar gliders of the regiment were being refitted to only carry Tetrarchs , and by late March the Locusts appear to have been completely replaced . This seems to have been due to mechanical and gunnery problems with the Locusts , as well as specific problems with the design of the Locust ' s gearbox . The regiment took part in Operation Tonga as part of 6th Airlanding Brigade in June 1944 , equipped with twenty Tetrarchs . However , due to their thin armor and underpowered armament they proved to be completely outclassed by the tanks and self - propelled guns deployed by German forces , such as the Panzer IV and the Sturmgeschütz III . By August , in preparation for the 6th Airborne Division ' s participation in the planned breakout from the Normandy bridgehead , the majority of Tetrarchs in ' A ' Squadron were replaced with Cromwell fast cruiser tank s ; only three Tetrarchs were retained , remaining with the Headquarters troop of ' A ' Squadron . In September the division returned to Britain and in the first week of October 1944 , the 6th Airborne Armoured Reconnaissance Regiment underwent an extensive reorganization . The regiment was completely restructured and retired all the remaining Tetrarch tanks it was equipped with , replacing them with Locusts . Operation Varsity . In March 1945 , the 6th Airborne Division was informed that it would be participating in Operation Varsity , an airborne operation in support of 21st Army Group crossing the River Rhine during Operation Plunder . On March 24 the division , in conjunction with the American United States 17th Airborne Division , would be dropped by parachute and glider near the city of Wesel , where it would capture the strategically important village of Hamminkeln , several important bridges over the River IJssel and the southern portion of a major forest , the Diersfordter Wald . Eight Locusts from the regiment , divided into two troops of four , would land with the 6th Airlanding Brigade in landing - zone ' P ' east of the Diersfordter Wald and west of Hamminkeln , acting as a divisional reserve ; the rest of the regiment would arrive by road after crossing the Rhine with 21st Army Group . The eight Locusts were loaded into separate Hamilcar gliders between 17 – 20 March , and on the morning of 24 March were towed from the airfield by Handley Page Halifax heavy bomber s to join the rest of the gliders and transport aircraft carrying the two airborne divisions . Weather conditions for the operation were excellent , with clear visibility , and all eight gliders arrived in the vicinity of the landing zone without incident . During their attempts to land , however , the small force was severely depleted ; one glider broke away from the Halifax towing it and disintegrated , apparently as a result of structural failure , with the Locust inside it falling to the ground . Three more gliders came under heavy German anti - aircraft fire and crashed as they landed ; one tank survived with a damaged machine gun , another crashed through a house which put its wireless radio set and main armament out of action , and the third broke loose of the glider as it landed and was flipped over onto its turret , rendering it useless . Six Locusts landed intact on the landing zone , including several with significant damage , but two of these tanks would never reach the rendezvous point chosen for the regiment . One undamaged tank came to the aid of a group of American paratroopers who were under fire from a German self - propelled gun but was rapidly knocked out by the German vehicle , wounding two crewmembers . A second tank broke down as it attempted to tow a jeep out of a crashed glider , although the crew remained with the tank and supported British airborne troops in the area . Of the four Locusts that reached the rendezvous point , only two were undamaged and fully fit for action ; these two were immediately deployed to the high ground east of the Diersfordter Wald , while being covered by the two damaged tanks . Upon arrival they were engaged by German troops and had to be supported by an infantry company , and soon their presence began attracting a great deal of artillery and anti - tank fire . Although neither of the tanks were hit , a number of infantrymen were killed or wounded and after several hours the tanks were forced to withdraw . The four tanks and remaining infantry formed a small force that repelled several German attempts to attack their position , and were eventually relieved at 10 : 30 by a tank squadron from the 44th Royal Tank Regiment and elements of the rest of the 6th Airborne Armoured Reconnaissance Regiment . Post - war . Operation Varsity was the only time the Locust would see action with the 6th Airborne Armoured Reconnaissance Regiment or the British Army as a whole . A report issued at the end of a conference held by the Director ( Air ) of the War Office in January 1946 confirmed that the Locust design was considered obsolete ; any light tanks to be used in post - war airborne formations would be made from completely new designs . The British Army disposed of a small number of Locusts by transferring them to foreign militaries . Several had their main armaments removed and were used by the Belgian Army as command tanks for their M4 Sherman regiments , and a few Locusts even found their way to the United States of America , where they had their turrets removed and served as agricultural tractors . A larger number of Locusts served with the Egyptian Army , replacing a number of older tank models , such as the Vickers - Armstrong Mark V light tank , that the Egyptian military had acquired during the interwar period . Several company - sized units of Locusts were used by the Egyptians during the 1948 Arab – Israeli War .