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Posted on 03/09/2004 12:04:50 AM PST by SAMWolf
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 are acknowledged, affirmed and commemorated.
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| Our Mission: The FReeper Foxhole is dedicated to Veterans of our Nation's military forces and to others who are affected in their relationships with Veterans. In the FReeper Foxhole, Veterans or their family members should feel free to address their specific circumstances or whatever issues concern them in an atmosphere of peace, understanding, brotherhood and support. The FReeper Foxhole hopes to share with it's readers an open forum where we can learn about and discuss military history, military news and other topics of concern or interest to our readers be they Veteran's, Current Duty or anyone interested in what we have to offer. If the Foxhole makes someone appreciate, even a little, what others have sacrificed for us, then it has accomplished one of it's missions. We hope the Foxhole in some small way helps us to remember and honor those who came before us.
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(A22 Infantry Tank)  With the majority of their armoured vehicles abandoned or destroyed in France, the British had very few tanks left to defend themselves from Germany's presumed next move against their island kingdom. For that reason a number of new and untested weapons systems were quickly rushed into production, including a new heavily armoured, but slow moving, infantry tank known as the A22. This new tank arrived at training camps in June of 1941 with little in the way of field testing. Due to the hurried construction schedule there were many unfortunate mechanical problems with these vehicles. Luckily for the using troops, most of these problems would be solved by the time the tank saw its first action in 1942. In the end, the Churchill in all its different forms (there would eventually be eleven Marks) was destined to become one of the most important British tanks in WWII. The 9th Battalion Royal Tank Regiment had been allocated the role of a heavy tank unit, and would therefore be armed with heavy, or infantry tanks. The British Army's policy in the late 1930's was to have three broad categories of tank, namely: light, lightly armed and armoured, to serve as scouts; cruiser, with high velocity two pounder guns, that could use their speed and range to carry out long distance strikes; and the infantry tank, slow, heavily armoured, working alongside the infantry and having a tough hide to absorb punishment.  Britain began the war with two infantry tanks, the Mark I and the Mark II. Mark I was a small two man tank equipped with one machine gun; although heavily armoured and reliable it was out of context almost as soon as it was produced. Mark II, the Matilda, was by contrast a classic for a limited period. In the years 1939 to 1941 it was one of the best protected and best armed tanks in any army, but it was not easy to produce and did not appear in the right quantities until it had been outclassed. Mark III Infantry tank was the Valentine, so called because its design was submitted to the War Office on St. Valentine's Day 1938. Production was not authorized until July 1939 and the production deliveries were made in late 1940. More than 8,000 Valentines were produced, but by late 1942 it was largely obsolete because of its low speed and small turret. In September 1939 the General Staff requested the engineering firm Harland and Wolff in Belfast to design an extra large infantry tank based on World War I principles; this was designated the A20. The first prototypes were delivered in June 1940, at a time when the British Army was desperately short of every type of fighting vehicle. To speed up production the A20 was scaled down to a design designated A22, which was given the name "Churchill". The re-design was done by the Director of Tank Design, Dr. H.E. Merritt, and a team of engineers from Vauxhall Motors. Vauxhall Motors were then instructed to have the tank in production by June 1941, a time schedule so tight that it allowed no time for user or development trials.  Vauxhall succeeded in making the schedule, but were so conscious of the vehicle's deficiencies that they included in the user's handbook a disclaimer, which is here partly quoted and partly paraphrased: "All those things which we know are not as they should be will be put right. In nearly every case the cure has already been found, and it will be introduced as soon as the new materials or parts become available. We are aware of defects, but basically the Churchill is a good tank. In these abnormal times it is thought better to produce the tank as it is, and to carry out the modifications we know to be necessary in the field units". The first Churchills certainly met the expectations of Vauxhall Motors in proving extremely unreliable. To combat the mechanical problems and the deficiencies in armour and armament, various changes were made in 1941 and 1942. These resulted in Churchills Marks I to IV. Subsequent developments were the Mark V, which had as its main armament a 95mm close support howitzer; the Mark VI, which had a 75mm gun as its main armament; and the Mark VII (same as Mark VI but with thicker armour) and Mark VIII (same as Mark V but with thicker armour). The specifications of each Mark are given in brief in Table V-1.  Features common to all Marks:
The hull of the Churchill was in the shape of a long, low box with a step at the front. The layout of the tank was in four compartments. The driving compartment housed the driver and hull gunner. Behind this was the fighting compartment which contained the completely rotatable turret; the turret housed the vehicle commander, gunner, and loader-operator, making a total crew of five for each tank. The engine compartment contained the engine, radiators, and petrol tanks, and on the outside of this compartment were bolted on each side the air intakes or louvres. The rear compartment contained the gearbox, steering and main brakes, air compressor and the auxiliary and power traverse generators.  One of the peculiarities of the design was the configuration of the air intakes. There was one intake on each side of the hull, and there had to be a substantial aperture in the armour of the engine compartment to let the air in. But the designers could not allow the engine to be exposed through this aperture, and so developed the air louvres very evident in many illustrations. There were two significant features of this arrangement. One was the projection of the louvre by some 9 inches from the hull of the tank, giving the tank extra width occasionally forgotten or ignored by the commanders or drivers. The second was the presence of the "chocolate bar", a slab of armour to protect the aperture in the hull. This was bolted on to the outside of the air louvres, and occasionally had to be removed. It was made of 2½ inch armour plate, and bolting it back on was a task to generate swearing, damaged limbs, and hernias. The engine, as shown in Table V-1, was a twin-six 12-cylinder horizontally opposed Bedford of 120h.p. RAC rating developing 350 brake horse-power at 2,200rpm. It was reputed to have been brought into production status in 90 days, an amazing performance; this miracle was also said to have been wrought by the simple expedient of taking two Bedford lorry engines - for which Vauxhalls were renowned - laying them on their sides facing inwards and attaching them to a common crankshaft. The rest of the job was locating all the ancillary components where they were secure and reasonably accessible. It must be said that the engine itself was very reliable; there is a story, maybe apocryphal, that one tank had a shell penetrate one half of its engine but managed to hobble to safety on the other half. The Churchill had a Merritt-Brown 4-speed constant mesh epicyclic gear-box. The steering mechanism, which was part of the gearbox, consisted of two steering drums, either of which could be locked by pressure of its brake shoe. When one of the steering drums was locked the speed of one track was reduced and the speed of the other increased, thus causing the tank to turn. The lower the gear that the tank was in, the sharper the turn. The system generally was called controlled differential steering, and the Churchill was the first British tank to have such a system. One of its real peculiarities was that it allowed the tank to turn on its own axis when in neutral. The turn was particularly sharp and sudden when on a smooth surface, giving rise to a stern warning in the driver's handbook ("do not do it!") and occasionally to much shouting and abuse of the driver when he did it. Although to be fair, it was a very useful capability properly used.  Churchill Crocodile The theory of the Merritt-Brown gear-box was such that it was reputed to have driven one of its creators off his head. It was certainly not easy for the trainee tankman to understand, but just occasionally could result in a benefit. Freddie Smart (who was leader of 6 Troop in B Squadron for the battalion's first actions, and who was killed by an S-mine on 26 July 1944) was one such beneficiary. One afternoon when he was a trooper at 56 Training Regiment Freddie's troop was being trained in the mysteries of the Churchill gearbox. The corporal instructor was suddenly informed that the Commanding Officer was coming round to inspect the training. It would be a good thing, the corporal was told, to have one of the recruits demonstrating his knowledge. Any volunteers? said the corporal. Yes, said Freddie, ignoring the age-old military maxim "never volunteer". So when the Colonel came round Freddie was explaining how the Churchill gearbox worked - and he did, in fact, understand it quite well. The Colonel, who probably had no idea how it worked, was impressed. Is this man down for a selection board? Freddie heard him ask. The upshot was that Freddie went through the various selection boards, pre-OCTU and OCTU, and ended up as a troop leader with the 9th. One of the features of the Churchill was that it was a surprisingly roomy tank. This resulted largely from the suspension system, as is evident from the side views of the tank and the picture of the hull body. The bogie wheels (or bogies) that supported the tank were quite small. Their reduced height, and the way that the track went right round the outside of the hull, meant that there was substantial storage space in the sponsons between the main compartments and the outside walls of the tank. A resulting disadvantage of this was that there were twenty-two bogies, and they all had to be greased every day.  Churchill ARVE in La Breche, Normandy on June 6, 1944. Just off of Sword Beach with the 3rd Division The ratio between the power of the engine (350 b.h.p.) and the weight of the tank (between 39 and 43 tons, depending on the Mark) gave a maximum speed of 15 m.p.h. on road and 8 m.p.h. across country for Marks I to VI. The increased armour and thus weight for Marks VII and VIII reduced their speeds to 12 m.p.h. on road and 6 m.p.h. across country. But then it was intended to be an infantry tank and not move too fast. The crew of five manning the Churchill each had their specific roles. But because of the technical tank training they had all been through, and because of the team spirit inherent in small groups living in urgent situations, most people were multi-skilled - although it has to be said that not many tank commanders were good cooks. The gunner aimed and fired the main armament and the machine gun mounted alongside it; the machine gun, which was a 7.92mm Besa was "coaxially" mounted with the main gun, and was generally referred to as "the coax" (pronounced coe-axe). The gunner was also responsible for cleaning and maintaining the main gun and the coax, although he would need help from other members of the crew.  Armored Vehicle Royal Engineers. A Petard 29cm caliber mortar was fitted to turret. Fired 40lb bomb 80 yards. 180 available by D-Day. 1st Assault Brigade of 79th Armored Division. 574 more were converted. Some were equipped to care fascines and CIRD for mine-clearing. The wireless operator was responsible for maintaining communication with the outside world, both through the medium range "A" set and the short range "B" set. The A set could be adjusted to different frequencies and the regimental frequency was changed regularly to help ensure security. Every morning the wireless "op" made sure that his set was properly tuned to the regimental frequency, a process known as "netting in" - sometimes called in the words of coarser minds "getting netted". The wireless op was also responsible for loading the main gun and for feeding the ammunition belts through to the coax. The co-driver, alternatively called the hull gunner, acted as a spare driver and fired and maintained the hull gun. This was a 7.92mm Besa machine gun, identical to the coax. The co-driver's direct personal duties were less onerous than those of the other members of the crew, but he acted as a helper to all other members of the crew, and in action he was in by far the most convenient position to make a brew of tea.  Churchill ARVE towing a trailer, and a Churchill fascine carrier behind. The man on top of the fascine is passing directions to the commander who in turns passes it on to the driver. The tank commander had total responsibility for his tank. In action this meant that it was always capable of fighting, and was fought well. As far as possible the tank commander kept the tank and its crew fit to move and fight by using his own resources, but should problems arise that he could not deal with, such as mechanical breakdown, he was responsible both for reporting the condition, and applying for the resources to correct it - for example the squadron fitters. He was responsible for instructing the crew over the intercom regarding start up, the route to take, gun control etc., all to a laid down set of instructions. The survival of tank and crew were very dependent on his keen observation and assessment of the situation. The tank commander was generally promoted from having been a crew member, and thus had experience of the duties of at least one crew position. But all crew members helped each other, and many tasks were naturally shared, such as replenishing the petrol or ammunition, cleaning the main gun, mending and adjusting the tracks, and tasks of maintenance and living.  The driver drove the tank, and made sure that it was fit to drive. It had to be full of petrol, all systems working properly as shown on the instrument panel, tracks properly adjusted, engine compartment as clean as possible, air louvres kept clear, periscopes kept clean, and so on. The driver had to follow a specific routine in starting the tank; this consisted of actions
These were all itemised in the driver's handbook. As an example, the procedure for starting a Churchill is given below. It shows that unlike most vehicles the Churchill required four people to participate in starting up.
After starting the engine, the driver had to check that all systems were working properly. He could then drive off. The drivers handbook describes the main features of driving a Churchill, particularly the process of changing gear. It reads very much like a book on golf, giving you so many points to remember that a satisfactory performance comes only by instinct or luck. Three examples are taken from the handbook to show the number of points that had to be remembered. Before reading them, however, we should bear in mind that:
"To engage gear when stationary, depress the clutch pedal onto the clutch stop firmly but not too hard and listen for the compressor to die down. Just before the compressor stops (which means that the clutch is also just stopping) push the gear lever firmly into the gear required. Pressing the clutch pedal on to the clutch stop very hard stops the clutch immediately and more than likely the gear will not engage. If this should happen return the gear lever to neutral and start again allowing the clutch to stop gradually".  "To change from second to third on the level or uphill with a rolling speed of less than 5 m.p.h., slow down in second until the tachometer is at 1500/1600 r.p.m. Make a fast racing change, using three fingers only with full use of clutch stop but no force. Flick the gear lever across from second to third quickly but lightly. Open the throttle immediately third gear is engaged. Never use both hands to make engagement and use the slow double declutch change whenever possible to save gearbox strain". "General advice: learn the corresponding engine revolutions for each mile per hour in the different gears. Accurate gear changing is quite simple providing the tachometer and speedometer are watched. Do not change up on slopes steep enough to cause the tank to accelerate and never change down on a down-hill gradient. If a lower gear has not already been engaged for safety reasons on a steep hill and the gradient becomes steeper, turn slowly to the left and stop, get into second gear and re-start." Surely to remember all these instructions a driver deserved extra money? And he got it! Cyril Rees recalls: "As a result of the experience I had gained I was successful in passing a trade test and being upgraded to a Driver Mechanic Class 2. This meant a pay increase to 6s 6d per day - what riches, and all found to boot!" The mechanical performance of the Churchill was initially abysmal, as described in this Appendix and the main body of the text. It gradually improved, and by 1944 and 1945 it was reasonably reliable.  The Churchill was always a good cross-country performer. In particular, it was good at climbing, and, considering its weight, it was very good at making its way across sodden and muddy country. The climbing skill was very evident in the battle of Steamroller Hill in North Africa (28 Feb 1943). The capability in mud was experienced by the 9th in Holland in October 1944 and again in the Reichswald in February 1945. In the initial stages of the Reichswald battle, prior to entering the forest, the gun tank Churchills were one of the very few vehicles that could keep going. From the very beginning the armour of the Churchill was good at absorbing punishment. This has been described in almost every action where Churchills were engaged; Dieppe, North Africa, Italy, Normandy, and all the other battles of NW Europe.  Compared with most of its opponents the main armament of the Churchill was always pathetic. In "Tank versus Tank" Kenneth Macksey tables that:
Churchills could and did knock out Tigers and Panthers by attacking from the side or the back, by breaking the tracks or by damaging the turret ring. But it took a lot of courage, skill and luck to get into the right position to do this. The under-gunning of allied tanks was an outrageously criminal lack of concern by the War Office. It resulted in what was in effect the murder of thousands of tank crewmen, a series of acts for which the War Office seems incapable of accepting responsibility.
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Air Power |
In order to understand something of the way aircraft were designed in the Soviet Union before the War a little explanation is needed here, since the design proces of the Pe-2 is the perfect role model.
Vladimir Petlyakov was one of the best assistants of Andrei Tupolev at the TsAGI (Tsentral'nyi Aerogidrodynamichesky Institut - Central Aerodynamics and Hydrodynamics Institute) from 1921, and played a major part in the creation of many Tupolev aircraft. Tupolev was a strong believer in the use of metal structures, and Petlyakov became an expert in light alloy structures after learning the basics of this science with Junkers, which was the world leader in light alloy structures for aircraft during the 1920s. Up to 1935 Petlyakov was largely responsible for the light alloy wings of aircraft such as the TB-1 and TB-3, and in Tupolev’s absence on the USA learning about American design concepts was wholly responsible for the development of the TB-4 and ANT-20. In 1936 Petlyakov was appointed manager of the ZOK, which was the factory for special construction attached to the TsAGI, and as such more or less designed the ANT-42 that was later renamed as the Petlyakov Pe-8.
In 1937 Petlyakov was arrested, possibly in relation to Tupolev’s similar arrest for allegedly selling the design of the VI-100 fighter to the Germans for transformation into the Messerschmitt Bf 110 heavy fighter. Petlyakov was imprisoned at a special unit and given the assignment of designing a high-altitude fighter under the auspices of the KB-100 design brigade with A.M. Izakson as his assistant. Such was the success of the design, which finally appeared as the VI-100 and formed the basis of the Pe-2, that Petlyakov was released and installed as head of his own design bureau in July 1940. Sadly, Petlyakov was killed in January 1942 when the second Pe-2 off the production line, which he was using as the bureau’s liaison aeroplane, caught fire in the air and crashed. Petlyakov was succeeded successively by Izakson, A.I. Putilov and, from 1943, V.M. Myasishchyev who were thus responsible for all later Pe-2 developments. The Petlyakov Design Bureau was closed in 1946.
The origins of the Pe-2 can be found in the VI-100 (Vysotnyi Istrebitel-100, or high-altitude fighter type '100') prototype that first flew in 1939 or 1940 as a cantilever low-wing monoplane of basically all-metal construction with with the exception of its fabric-covered control surfaces. It must be noted here that '100' is in no way a sequence number, but merely a reference to the bureau were it was developed: STO. STO is also the word for the numeral '100' in the Russian language. The office was placed inside a complex, and staffed with imprisonned designers like Petlyakov. The VI-100 was of conventional layout but an extremely advanced design with turbocharged engines, radiators installed in wing ducts with four upper-surface exits rather than in exterior baths, no hydraulics but a powerful 28-volt electrical system with some 50 actuators controlling most of the moving parts, a pressurized cockpit with tandem two-seat accommodation for the pilot and radio operator/gunner, a dihedraled tailplane carrying endplate vertical surfaces and fully retractable tailwheel landing gear including main units that retracted rearward into the underside of the nacelles for the two wing-mounted Klimov M-105 (later VK-105) Vee engines, rated at 1,050 hp (783 kW) for take-off each.
The VI-100 had a gun armament of four 0.3 inch (7,62 mm) ShKAS machine guns with 600 rounds per gun in the nose, and one 0.3 inch (7,62 mm) ShKAS trainable rearward-firing machine guns in the rear cockpit, which was located over the trailing edge of the wing roots at some distance from the pilot’s cockpit over the leading edge of the wing roots in an installation that was finally unpressurised because of delays in finalisation of the pressurised cockpit by M.N. Petrov’s brigade. The VI-100 revealed good performance and handling, but was difficult and expensive to produce. In May 1940 its was therefore decided that further development would be concentrated on the PB-100 (Pikiruyushchii Bombardirovshchik-100, or dive-bomber type '100') with no provision for a pressurized cabin, provision for a prone navigator/bombardier below and ahead of the pilot in the nose below floor level, and the powerplant revised from the use of two TK-3 turbochargers to two TK-2 turbochargers. Two armament fits were proposed: one was based on the use of eight 0.3 inch (7,62 mm) ShKAS machine guns as a quartet of fixed forward-firing weapons in the nose and two pairs of trainable rearward-firing weapons installed in the dorsal and ventral positions; and the other was based on the use of two 20 mm ShVAK cannon and two 0.3 inch (7,62 mm) ShKAS machine guns trainably mounted in an underfuselage box so that the weapons (located in mixed pairs at the front and rear of the box with the cannon on the right and the machine gun on the left) could be fired obliquely forward/rearward and at any angle of depression to a maximum of -40°. The disposable armament was a maximum of 2,205 lb (1.000 kg) including 1,323 lb (600 kg) carried internally in a lower-fuselage weapons bay.
The PB-100 prototype was produced as a conversion of the second VI-100 prototype, and made its maiden flight in June 1940. Later in the same month the decision was taken for the PB-100 to be placed in immediate production with a number of minor changes as the Petlyakov Pe-2, and in the following month Petlyakov and the other members of his design team were released from detention. The Pe-2 used basically the same airframe as the PB-100 but had revised accommodation, M-105R Vee engines without turbochargers and installed in different nacelles, a hydraulic actuation system for the main landing gear units, enlarged vertical tail surfaces, and improvements to the protection for the crew and fuel tanks. The opportunity was also taken to revise the airframe structure as a means of facilitating mass production.
The Pe-2 was of basically all-metal construction, and its core was a fuselage of nearly circular cross section. This carried the flying surfaces, which comprised a dihedraled tailplane with endplate vertical surfaces, and a low-set wing that was based on a flat center section that was tapered in thickness and slightly in chord (the leading edges were straight and the tailing edges marginally tapered), and carried dihedraled outer panels that were tapered in thickness and chord. The moving surfaces on the wing comprised the standard trailing-edge combination of outboard ailerons and inboard flaps (the latter of the Shrenk type) and underwing dive brakes of the Venetian blind type. These last were controlled by the AP-1 automatic dive-control system that was later removed to allow direct control of these surfaces by the pilot. This automatic dive-control system is likely derived from purchased Junkers Ju 88A dive bombers. The airframe was completed by the tailwheel landing gear, which was fully retractable with main units that folded rearward into the underside of the nacelles for the two wing-mounted engines. The accommodation was centered on a large and comfortable cockpit under a framed, glazed canopy. The cockpit was set farther forward along the upper part of the fuselage than had been the case in the VI-100 and PB-100, and provided accommodation for the pilot on the left with the navigator/bombardier behind him and to the right. The navigator/bombardier was seated facing the rear, and operated the 0.3 inch (7,62 mm) ShKAS trainable machine gun that was the Pe-2’s main defensive weapon against attacks from above and the rear, and for the attack phase of the mission moved to a prone bombardier position in the glazed lower part of the extreme nose. The other member of the crew was the radio operator/gunner in a separate compartment to the rear of the fuselage fuel tank under a glazed roof panel and with an oval window on each side: the defensive weapon controlled by this man was a 0.3 inch (7,62 mm) ShKAS trainable rearward-firing weapon in a retractable installation. The rest of the gun armament comprised two 0.3 inch (7,62 mm) ShKAS fixed forward-firing weapons on the sides of the forward fuselage in an installation controlled by the pilot.
The disposable armament was normally four 220 lb (100 kg) FAB-100 bombs in the lower-fuselage weapons bay and/or four 551 lb (250 kg) FAB-250 bombs carried on four hardpoints under the inner wing panels, but there was also provision for two 220 lb (100 kg) FAB-100 bombs in the rear of each engine nacelle. The powerplant initially comprised two Klimov M-105RA Vee engines, rated at 1,100 hp (820 kW) for take-off each, and driving a three-blade VISh-61 metal propeller of the constant-speed type. These engines were supplied with fuel from five rubberized fabric tanks (one in the fuselage, two in the inner wing panels and two in the outer wing panels) that were inerted by cooled engine exhaust gases (against fire or explosions). The fuel capacity originally totaled 239 Imp gal (287 US gal, 1.086 liters) but was later increased to a total of 326 Imp gal (392 US gal, 1.484 liters) by enlarging the fuselage tank and adding three new tanks (one in the center section and two in the outer wing panels outboard of the original tanks). The nickname 'Peshka' ('Little Pe' or 'Pawn') was applied to the aircraft both by the industry and the air force. I can only guess for the real reason of the name, except that the other major design of Vladimir Petlyakov was the Pe-8 (TB-7). This four-engined bomber was huge, dwarfing the Pe-2 (and Pe-3 which had the same ancestor as the Pe-2).
Specifications:
Manufacturer: Petlyakov
Roles: (Ground) Attack Fighter, Fighter-bomber, Long range (attack) Fighter, Light Bomber, Dive Bomber, Reconnaissance Aircraft
Powerplant: 2 × Klimov VK-105PF Vee, rated at 1260 hp each
Crew: 4 - pilot, navigator/bombardier, radio operator/gunner, gunner
Dimensions:
Wingspan: 56 feet 3.5 inches
Wing area: 435.9 sq_feet
Length: 41 feet 6.5 inches
Height: 13 feet 1.5 inches
Empty weight: 12,943 pounds
Max loaded weight: 18,730 pounds
Performance :
Maximum speed: 335 MPH / 290 KT
Service ceiling: 28,900 feet
Range: 932 MI / 810 NMI
Armaments:
Machine guns
Three 12.7mm cannon,
Two to Four 7.62mm MG depending on model
Bomb load:
Four 551 lb FAB-250 bombs in weapons bay
Six 220 lb FAB-100 bombs at the other positions
Champers is rarely my beverage of choice, and rarely Moet's. But it'll be very easy for me to keep your thought in mind.
The 57mm/2¼-inch shot round would penetrate a little better than the equivalent 75mm [3-inch] APC [Armor-piercing, capped] solid projectile, due to having similar velocity, but the 57mm projo having a little better shape and lesser frontal area. But the 76mm HVAP or *hypershot* ammunition was the real tank killer, especially in the Buick M18 Tank Destroyer, in which the new ammunition was first field tested.
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