News from Heroes and Leaders mod

asl3d · Post by **asl3d** » Sat Jan 16, 2021 4:52 pm

US LTV4 MG Amtank aAPC

One of the largest defects of the LVT-1 and LVT-2 was the central localization of the cargo-space what did not facilitate the the loading and unloading. To increase the carrying capacity of the LVT2, two new models were designed in 1943. The first to be used in combat was the LVT4, which had the engine moved forward from the stern to behind the driver's cab so that a manually operated ramp could be incorporated at the stern. This ramp allowed quick on- and off-loading, and even enabled the LVT4 to carry a small vehicle. This provision had as a reason the localization to the back of the engine compartment. To reach or leave the vehicle, the passenger were to climb or jump over the sides. During an attack, it was quasi suicidal. The driveshaft which from the engine traversed all cargo-space until the transmission, limited the possibilities of loading of material. (The LVT3, also known as the Bushmaster, was not used operationally until the landings on Okinawa in April 1945 and is equivalent to the LVT4.) As originally built, the LVT4 was armored only on the cab and ramp but most were modified by the use of bolt-on armor kits and so are treated as AFV.
To solve this problem the FMC decided to modify the LVT-2 by moving the engine compartment from the back of the vehicle, just behind the cockpit and installing to the back an access ramp. Thanks to this slope assembled on hinges, the access to the vehicle was easy, as well as the evacuation of the passengers. This provision was more making safe for the infantrymen who left the vehicle by the back, this last offering to them thanks to its mass a protection against the enemy snippers. One could now charge more easily and quickly material as well as a Jeep or an howitzer of 105 mm. The capacity of loading of the LVT-4 was of approximately 4 tons or 30 passengers (removable benches were installed). The LVT-4 was 7.95 m long, 3.25 m broad, 2.50 m in height and weighed 16500 kg. Let us note that the sides of the LVT-4 were prolonged more in height.
Marines and the Navy were impressed by the new possibilities that offered this new design and ordered its setting in production immediate. The LVT-4 which preceded the LVT-3 at the time of its service entrance was manufactured to 8438 specimens by the FMC, Graham-Paige and St Louis Car Co in 1944-1945, making them the most numerous LVT type during WW2. This total was divided between the Ground Army (6083), the Marines (1765) and the allied countries (503). They first saw action during the Saipan landings. The LVT2 and (A)2 were nicknamed "Water Buffalo", while all LVT were referred to generically as "amtracs" (amphibious tractors) or "alligators". More than 18,600 LVT of all types were produced during WW2.

asl3d · Post by **asl3d** » Sun Jan 17, 2021 3:48 pm

US LVT(A)1 T37LL Amtank AmphLT

Because of the risks to meet a Japanese armoured opposition at the time of the reconquest of the Pacific, the Marines wished to have an armoured LVT, armed with a turret with gun able to face there. "LVT" stands for "Landing Vehicle, Tracked", while "(A)" indicates that it was constructed using armor plate (rather than soft steel). After the near-disaster at Tarawa, it was decided that in future assault landings the initial wave would need an armored type of LVT, plus amphibious tanks for close support. This resulted in the LVT(A)2, and also the LVT(A)1 which consisted of an LVT(A)2 with its cargo compartment roofed-over to carry a turret derived from that on the M5A1 Light Tank. In addition, on both sides of the turret and aft of it was a scarf-mounted .30-cal MG operated by a gunner who stood through a hole in the roof.
To create a closed compartment of combat, the cabin was prolonged over the three-quarter of the space-cargo. This compartment comprised a trap door assembled on hinge on each side like two trap doors also assembled on hinges on the roof. The roof of the compartment of combat also accomodated the circular of 1.187 m of the turret. The compartment of combat also accomodated the 104 projectiles of 37 mm and the 6000 cartridges of 7.62 mm embarked.
The selected turret was that of the M3A1 Light Tank. However, the rear bulge which accomodated the radio station was removed, because there was enough space in the interior of the hull to accomodate the radio equipment. Traverse was done by means of a hydraulic system or manually. Elevation was made as for it manually (maximum depression: -10° - maximum elevation:+25°). The gun was provided with a gyrostabilisator to allow the use of the weapon when the vehicle is moving. This device was quasi useless in water because of rolling and the pitching which prevented any precise shooting. The gun of 37 mm M6 was assembled on a M44 mounting with a coaxial machine-gun of 7.62 mm (.30cal). The gun of 37 mm M6 had a length of 56 calibers and an initial speed varying between 776 and 884 m/s. The gun of 37 mm could transpierce 48 mm of shielding under 30° with 500 m. It fired only piercing projectiles. Let us note that the breech-block of M6 was semi-automatic. The devices of vision of the turret comprised in more of the sight tube assembled on the mantlet, on the roof two rotary episcopes and a fixed episcope. The two trap doors of access located at the back of the roof of the turret were assembled on hinges. The turret did not lay out another armament separately the gun and the coaxial machine-gun. To ensure the defense of the back against the attacks of the enemy infantrymen, two stations of machine-guns of 7.92 mm (.30cal) were to create to the back of the old cargo-space. They were two circular holes pierced in an armour-plate covering the back of the cargo-space, just behind the superstructure of the compartment of combat.
509 were built, and their first combat use was in the Kwajalein Atoll landings with the Army's 708th Amphibian Tank Battalion and the Marines' 1st Armored Amphibian Battalion. An LVT(A)1 or (A)4 platoon consisted of five vehicles (of one or both types), although in action there were usually six since one of the three company HQ LVT(A)1/(A)4s accompanied the platoon.

asl3d · Post by **asl3d** » Mon Jan 18, 2021 3:45 pm

US LVT(A)4 T75* Amtank AmphLT

The inability of the LVT(A)1 to deal with heavily fortified positions led to the development of another amphibious tank based on the LVT(A)2 but having greater HE firepower. The LVT(A)4 Amtank differed from the (A)1 by carrying the turret of the M8 HMC and not having scarf-mounted MG positions. Although having a swiftness of half less than that of the gun of 37 mm, this weapon was able with high-explosive shells to destroy the Japanese bunkers and its effects were more devastators. Unfortunately, its OT turret and weaker MG FP made it more vulnerable to Japanese close assault tactics, so extra MG began to appear on it almost immediately after its introduction.
The first cabins were equipped with only one window of vision (with armoured shutter) and of two trap doors of access with rotary episcopes on the roof. The first LVT(A)-4s missed means to ensure a frontal brought closer defense against the Japanese kamikazes infantrymen. Thereafter a new cabin was installed with a machine-gun of 7.62 mm (.30cal) assembled on ball on the frontal plate of the cabin. On this cabin, the episcopes of the trap doors were removed. The vision of the crew of the cabin was ensured by four ports of vision laid out on the sides and the frontal plate of the cabin. Starting from the reconquest of Mariannes, certain crews replaced the machine-gun of 12.7 mm (.50cal) by two machine-guns of 7.62 mm assembled on pivots on the sides of the turret. These machine-guns could easily cover with their fire the sides as well as front and the back of the tank. Though that was the arrangement of the secondary armament of the turret, this one was equipped with shields.
The side walls of the compartment of combat of the LVT(A)-4 were tilted. This compartment comprised a trap door assembled on hinge on each side like two trap doors also assembled on hinges on the roof. The roof of the compartment of combat also accomodated the circular of 1.38 m of the turret, this circular was broader than the roof of the compartment and thus made covered on the sides. The compartment of combat also accomodated the 100 projectiles of 75 mm and the cartridges of the embarked machine-guns. The turret which did not have a roof could swivel (manually) on 360° and the howitzer had a maximum depression of 20° and a maximum elevation 40°.
The production of the LVT(A)-4 at FMC began in 1944 and one total of 1489 specimens was supplemented during this year, follow-ups by 401 other models in 1945. A total of 533 specimens was given to the Corps of the Marines which formed with them 3 Amtank Battalions. The Army in received 1307 and formed 7 Amtank Battalions. Their first combat use was at Saipan. Despite its "Tank" designation, the LVT(A)4 was intended to be used as an assault gun and SP artillery piece, and had been armed with a howitzer specifically for such a dual direct/indirect fire role.

asl3d · Post by **asl3d** » Tue Jan 19, 2021 4:02 pm

US M2 Bo MMG ht

The half-tracked vehicles knew their hours of glory during the second world war within the allied and the Axis forces. In fact only the Germans and the Americans developed and carried out in very great number of this kind of vehicle to form their divisions motorized. These vehicles had better cross-country capacities that the trucks and the armoured cars.
The M2 Halftrack Car was developed in 1939 by Diamond T Motor Car Co under the name of prototype T14 Halftrack APC based itself on the M2A1/M3 Scout Car (wheeled vehicle). Between 1940 and 1943, 11415 specimens were produced by White Motor Co. (8423) and Autocar Co. (2992). Among these specimens, let us note that 1266 were converted thereafter into M2A1 Halftrack Car. The M2 Halftrack was intended to be used as a recon vehicle (it replaced the M3A1 Scout Car in certain mechanized cavalry roles during 1943), mortar or MG carrier, and artillery prime mover.
The M2 as all halftracks was divided into three parts: the engine compartment in front (equipped with a frontal plate with armoured shutters protecting the radiator), the driving cab in the middle and the compartment of load to the back. The gasoline engine White 160AX of 6 cylinders developing 147 hp installed in front transmitted its power at the same time to the front procket-wheels of the tracked suspension and to the nose gear wheels which gave the steering. This excellent engine made it possible M2 to reach the 72 km/h on road and the 272 L of fuel load got an autonomy of 320 km to it on road (the principal fuel tanks were on the sides about the middle of the compartment of troop). The transmission Spicer 3461 comprised 5 speeds (4/1). The steering was obtained by means of a simple steering wheel. The tracked suspension included on each side a front sprocket-wheel with 18 teeth, a bogie truck equipped with 4 small steel road wheels and a return roller, and a back idler. Only the nose gear wheels were equipped with shock absorbers. The tracks used by M2 were in rubber with central guides. They were 300 mm wide and included each one 58 links.
The cabin accomodated two men: the driver sitting on the left and his assistant sitting on the right. The access to the cabin was done via the two side doors (with ports of vision). The windshield of the cabin was equipped with an armoured shutter equipped with two ports of vision. The cabin did not have a roof. Just behind the seats of the drivers (in the medium) was a third seat for the commander of the vehicle. The remainder of the back compartment was occupied by seats for 7 men and of the trunks of arrangement (behind the seats of the drivers). The access to the back compartment was done by the cabin (not partition between the two) because this one did not have back door. The back compartment as well as the cabin did not have a roof but could be covered with a hood. The armament consisted of a machine-gun .50cal (12.7 mm) M2HB and a machine-gun .30cal (7.62 mm) M1919A4 assembled on retractable mountings sliding along a rail making the whole of the back compartment and the cabin. In front, the M2 was equipped with a roller to protect the nose from the machine on the very broken grounds or with a winch. The shielding of M2 was 6.4 mm for all the faces safe for the armoured shutter of the windshield (13 mm).

asl3d · Post by **asl3d** » Wed Jan 20, 2021 4:19 pm

US M3 Bo MMG ht

Since 1937, several models of half-tracked vehicles of reconnaissance, artillery tractors, transport of troops or material were developed by Cunningham, Linn, GMC and Marmon-Herrington (series T1-T9E1) bound for the Cavalry and Artillery mechanized. The models of Cunningham were based on the chassis of the truck Ford 1.5-tone 4x2 Model 1936 combining wheeled nose and back tracked unit. These models all were equipped with the supports of road wheels of the Kégresse type however defective. These machines were used as transport material and personnel in many units of US mechanized divisions.
The US Cavalry wished to replace the Scout Cars (armoured cars of reconnaissance) by Halftracks better adapted to the difficult grounds. In 1938, M3 Scout Car was modified by the adoption of a tracked suspension in the place of its rear wheel-axle unit. The Infantry asked for its use a M2 Halftrack Car similar vehicle equipped with a longer hull to transport a section of Infantry. This new model was called T8 Halftrack Personnel Carrier which will be standardized as M3 Halftrack Personnel Carrier. The interior of the vehicle was also too narrow. The primary function of this halftrack was to carry the infantry of the armored divisions. It was slightly longer than the M2 and could seat thirteen including the driver. Its single .30-cal air-cooled MG was pedestal-mounted in the center-foward section of the passenger compartment. 12,499 were built.
The first models officially adopted by US Army was T14 Halftrack APC in 1939, developed by Diamond T Motor Car Co based the chassy and the body of the wheeled vehicle of cavalry M3A1 Scout Car. This model derived from T7 had been created at the request of Artillery but contrary to the model of Cavalry was equipped with a more powerful engine. During the tests in 1940, officers of Infantry were present and were struck by the potential of this kind of vehicle for their own weapon. In comparison to successes of the German mechanized troops (composed of semi or entirely tracked vehicles) during Blitzkrieg in 40-41, the Americans decided to produce in mass the halftracks from the end 1940 to equip their mechanized divisions in construction. The threats of a future engagement of the USA were felt more and more.
Marmon-Herrington and other manufacturers developed a new suspension using rubber tracks. This suspension gave excellent results and the Defence Department adopted it as bases for the future achievements. It will become the standard suspension of the M2/M3 Halftracks and all US half-tracked vehicles of the 40-45 war.
Compared to their German counterparts, U.S. halftracks had superior overall mobility by virtue of their higher top speed, driven front axles, and front bumper-mounted roller (to help prevent digging into the side of a ditch or steep incline) or winch. On the other hand, U.S. halftracks had no floor armor (thus making their occupants vulnerable to mines), higher ground pressure, and tracks that tended to wear out quickly.
A 1942-43 armored infantry platoon consisted of three M3, one M2, and one M3(MMG) halftrack; three M3 with one passenger squad each (and one 60mm MTR in one of the halftracks), one M2 towing a 37mm AT Gun and carrying its crew, and one M3(MMG) for MG support.

asl3d · Post by **asl3d** » Thu Jan 21, 2021 5:17 pm

US M3 GMC Bo B75 TDht

During the construction of the armoured forces, US Army divided the division of the roles well: to the battle tanks was entrusted the destruction of the enemy fortified towns and the support of the infantry, and to the tank destroyers the destruction of the enemy battle tanks. This provision gave birth in 1940 to Armoured Force (tanks) and to the Tank Destroyer Forces (tank destroyers). However, the latter did not have any vehicle able to play this part and the development of such machines was thus urgent. The first selected anti-tank gun was the 75 mm M1897, American version of the French veteran used in 1914-1918. US Army decided to mount this weapon on M3 Halftrack Personnel Carrier. This vehicle resulted from an urgent requirement to have some form of tank destroyer available until the M10 GMC could enter service. The M3 Gun Motor Carriage Halftrack used an M3 Halftrack modified to carry an M1897A4 field gun.
The gun of 75 mm was simply welded onto a box just behind the cockpit. The M3 could transport 90 projectiles of 75 mm arranged in racks under the gun (50) and in boxes on floor to the back of the vehicle (40). The fuel tanks were placed at the rear of the vehicle on each side to provide enough space for an acceptable traverse for the gun. The gun of 75 mm assembled on a mounting M3 could swivel of 19° on the left and 21° on the right. It had an elevation of 29° and a depression of 10°. Its effective range was approximately 914 m. It fired the high-explosive shells (HE) or smoke-producing.
The M3 was also equipped with a broad flat shield protecting in front, the gunners. After one test period, the M3 was accepted for the production under the designation of M3 75 mm Gun Motor Carriage (GMC). With the experiment of the first engagements in the Philippines, the flat shield was replaced by a shield equipped with walls side and closed to the top. An alternative which at the beginning was to be based on the M3A3 but finally based on the M3A2 was also produced under the name of M3A1 75 mm Gun Motor Carriage. The only difference between M3 75 mm GMC and the M3A1 75 mm GMC is that this last was equipped with a M5 mounting and not M3 as on the first. A total of 2203 specimens of the two models were produced in 1941 and 1942 per Autocar. Production began in late 1941, and in December of that year 50 arrived in the Philippines where they were used as SP artillery until the fall of Bataan. Altogether 2,202 were built, but 1,360 were later converted to M3A1 Halftrack Personnel Carrier when this half-tracked hunter of tank was considered to be obsolete and withdrawn from the service.
In the PTO the M3 GMC was used successfully by the USMC until the war's end, with each infantry regiment in a Marine division having a platoon of two (four after April 1944) in its weapons company, and until that same date the divisional Special Weapons battalion also had three such platoons. The M3 GMC was the only type of halftrack employed in Marine divisions. In Tunisia the M3 GMC was used in the 601st, 701st, 805th, 813th, and 894th TD Battalions (Heavy SP), with four per platoon. They met with mixed success in that campaign; their thin armor caused many to be knocked out, but when properly used in ambushes from HD positions they were effective vs Axis armor. M3 GMC were also used in Sicily by the 601st TD Battalion.

asl3d · Post by **asl3d** » Fri Jan 22, 2021 4:13 pm

M3 T37LL Lee MT

By mid 1940 the Army had come to the conclusion that its newest medium tank (the M2A1, which carried a 37mm gun and a multitude of MG, and which had not yet even entered mass production) was outclassed by the PzKpfw IV with its 75mm gun. What the Army now desired was a tank armed with a weapon at least equivalent to the German piece. The problem was that no turret capable of carrying such a powerful weapon had ever been built in the U.S., and the development of one would necessarily take time. Meanwhile, the British were in desperate need of new tanks to replace those lost in France. The Army therefore decided to modify the M2A1 and install both a turret-mounted version of the Army's 37mm AT gun, and a limited-traverse 75mm gun on the star-board side of its front hull. The resulting M3 Medium was viewed only as a stopgap solution until a proper 75mm tank could become available—but with the added benefit that the automotive bugs corrected on the M3 would expedite the Sherman's development since both would use essentially the same chassis. Other versions of the basic M3 were also produced, but in much smaller quantities; since they vary little in game terms they are not included in counter form.
The Model M3 was the principal model of the series and the only one to be product in mass. It was equipped with a riveted superstructure. The models of origin had side doors which will be welded or completely removed to the profit of a floor trap door. M3s were been driven by a Continental R975 EC2 gasoline engine, of 9 cylinders developing to the maximum 400 hp to 2400 revolutions per minute. The back plate of the hull had a double-trap door on hinges flanked of two air filters. M3 was baptized General Lee I by the British.
The gun of 75 mm was assembled in a casemate located in the front-right corner of the hull. This weapon assembled on M1 mounting had a length of 28.5 calibers (with or without counterweight in front of the tube to compensate the weight of the cylinder head) and an initial speed of 567 m/s and was much higher than the short gun (KwK L/24) of 75 mm which equipped at that time Pz.Kpfw IV and with the new gun of 50 mm (KwK L/60) of Pz.Kpfw IIIs. M2 could transpierce 60 mm of shielding under 30° to 450 mm and its explosive capacity was also very satisfactory. The gun was pointable until 15° on each side and had an elevation of 20° and a depression of 9°. The gun of 75 mm had a gyroscopic system of stabilization for the elevation, which made it possible to increase the precision of the shooting in evolution and especially in static fire. The block of the cylinder head of M2 was vertical. The periscope of the gunner on the circular roof of the casemate was replaced thereafter by a telescopic periscope.
In all, 6,258 were built, but only about 1,400 were retained by the U.S.; the rest were Lend-Leased to various allies. In U.S. service the M3 first official use came with the Torch landings and later in Tunisia with the 2nd and 3rd Battalions of the 1st Armored Division's 13th Armored Regiment. These battalions were equipped solely with M3 types until Shermans from the 2nd Armored Division began arriving to replace combat losses. At the conclusion of the Tunisian campaign all M3 Mediums were relegated to training roles. In the PTO, their only U.S. use occurred in Nov. 1943 when the 193rd Tank Battalion aided in the seizure of Makin Atoll.

asl3d · Post by **asl3d** » Sat Jan 23, 2021 4:48 pm

US M3 37LL Stuart LT

The light tank M3 Stuart is the result of a series of light tanks which began in 1931. However the development of M3 began really only in 1940 when Armored Force was created in June. Benefitting from the lesson of the campaign of France, the US designers modified light tank M2A4 by increasing its frontal shielding up to 51 mm and by installing an anti-aircraft machine-gun on the turret. The US M2A4 37LL was the Army's most modern light tank in 1940. 375 were built. It was a very reliable and well-armed light tank for its time, but was rapidly superseded by the improved M3 version. The M2A4 saw combat only on Guadalcanal with Company A of the 1st Marine Tank Battalion.
A large number of improvements were made to the M2A4 in early 1941, resulting in the M3 Light Tank. The hull was prolonged to cover the exhausts and the suspensions with helical springs was retained. The new model was baptized M3 Light Tank. It had a crew of 4 men: the commander, the gunner, the driver and his assistant. As the M2A4, M3 was armed with the standard gun M5 of 37 mm with gyro-stabilizers. The hull was assembled by bolting and accomodated a Continental W-670 of 250 hp gasoline engine. Armament was supplemented by five Browning machine-guns of 7.62 mm: an anti-aircraft mounted to the back of the turret, coaxial mounted with the right side of the gun, a machine-gun of hull assembled on the glacis and two others mounted on each sponsons. M3 was standardized in July 1940 and the production began in March 1941. The Continental W-670 gasoline engine was in fact an engine of plane and because of the priority given to the air force, this engine was not available in great number for M3. To fill this lack one used the diesel engine Guiberson but especially Twin Cadillac V8 gasoline developing 220 hp. This last equipped a new model the M3A2. 5,811 were built.
A small number were with the 1st Armored Division during the Torch landings and the subsequent fighting in Tunisia. In the PTO the 192nd and 194th Tank Battalions with a total of 108 M3 Lights (and no HE ammo) formed the core of the 1st Provisional Tank Group, which was employed in the defense of the Philippines (12/41-4/42); more than thirty of them were captured by the Japanese, whose 7th Tank Regiment used them against the returning Americans in 1944-45. M3 Light Tanks were also used on Guadalcanal (8-12/42) by Company B of the 1st Marine Tank Battalion. The M3 garnered the distinction of becoming the first U.S.-built AFV to see combat in WW2 when the British used it in Operation Crusader (11/41).
The US M3A1 37LL was an improved version of the M3 Light Tank, incorporating a remodelled turret, deletion of the two fixed BMG, and standardization of the gyrostabilizer. 4,621 were built. The M3A1 first saw action on Guadalcanal (9-12/42) with Company C of the 1st Marine Tank Battalion, and remained in widespread use with the Marines until early 1944 when the M5A1 Light Tank began to replace it. In North Africa, both Light Tank Battalions (1st of the 1st Armored Regiment and 1st of the 13th Armored Regiment) in the U.S. 1st Armored Division were equipped primarily with the M3A1.

asl3d · Post by **asl3d** » Sun Jan 24, 2021 4:40 pm

US M4DWG T75 AmphMT

The deep-wading kits were fitted to the tanks of the 2nd Armored Division in the bivouac areas near Bizerte in late June 1943. The armored landing teams assigned to the support of the infantry at the three beaches in southern Italy were landed from LCTs; the follow-on waves were landed from LSTs using pontoon bridges when necessary.
To transform a standard Sherman M4A1 into a Sherman M4 DWG (Deep Wading Gear) it needed to dedicate over 250 hours to waterproof a Sherman tank and to attach the wading kit, with much of the time consumed in waterproofing internal electrical systems to prevent short-circuiting and water damage. To simplify this process, US Ordnance Department in 1943 began a program to incorporate extensive waterproofing into all newly manufactured tactical vehicles including modified electrical harnesses and waterproofed electrical contact points. This proved to have very beneficial consequences during humid weather in the various combat theaters where previously there had been recurring problems with tank reliability due to water-induced damage to electrical systems.
The configuration of the deep-wading kit underwent continual evolution due to the interaction of Aberdeen Proving Ground, Ordnance Service—ETOUSA, and their British counterparts. The original mushroom shape of the Blue Freeze stacks was simplified into a question-mark shape with a larger opening towards the front of the tank. The stacks in 1942-43 were attached vertically to the adapters, but in 1944 a new design was adopted with the stacks angled slightly to the rear. This was done so that the stacks would fall off by gravity with a minimum of effort once the attachment was removed by the crew. A standard tank deep-wading kit in 1944 consisted of four main elements. The Tank Fording Kit T-0 consisted of the common waterproofing materials such as sealing compound, grease, glue, and other equipment needed to attach the kit to the tank. The Stack Fording Kit MT-S (Medium Tank-Stack) was a universal stack for medium tanks. Due to the different configuration of various Sherman engines, there were separate adapter fording kits for each type; the MT-1 for the M4/M4A1 medium tanks, and the MT-3 for the M4A3. There were corresponding kits for various other armored fighting vehicles; for example, the LT-5 kit for the M5A1 light tank, the SPA-7 for the M7 105mm HMC, and the SPA-10 for the M10 3in. GMC tank destroyer. Following the standardization of deep-wading kits in late 1944, Ordnance assigned them the usual SNL (standard nomenclature list) industrial parts designators; for example, G104-5700778 for the M4A3 medium tank kit.

asl3d · Post by **asl3d** » Mon Jan 25, 2021 4:26 pm

US M36 T90L Jackson TD

The M36 Gun Motor Carriage combined the hull of the M10 tank destroyer, which used the M4 Sherman's reliable chassis and drivetrain combined with sloped armor, and a massive new turret mounting the 90 mm gun M3. Tank destroyer units were meant to counter German blitzkrieg tactics. Tank destroyer units were to be held as a reserve at the corps or army level, and were to move quickly to the site of any massed enemy tank breakthrough, maneuvering aggressively and using ambush tactics (charging or chasing enemy tanks was explicitly prohibited) to destroy enemy tanks. This led to a requirement for very fast, well-armed vehicles. Though equipped with turrets (unlike most self-propelled anti-tank guns of the day), the typical American design was more heavily gunned, but more lightly armored, and thus more maneuverable, than a contemporary tank. The idea was to use speed and agility as a defense, rather than thick armor, to bring a powerful self-propelled gun into action against enemy tanks. The M36 was sometimes referred to as the "Jackson" or the "Slugger". 1,413 were built.
In late summer 1942 American engineers had begun analyzing the potential of designing a new tank destroyer armed with a 90mm gun. In October 1942, the Ordnance Department tested mounting the experimental 90 mm gun T7 into the turret of an M10 tank destroyer. Mounting the 90 mm gun was straightforward, but the gun proved too heavy for the M10's turret. A new turret was designed that incorporated power traverse and a massive counterweight to balance the gun. The first two M36 prototypes, designated 90 mm Gun Motor Carriage T71 were completed in September 1943. The ring mount on the left side of the turret for the .50 caliber Browning M2HB antiaircraft machine gun was changed to a pintle mount at the rear. It was decided that production vehicles would use the chassis of the M10A1.
The M36 was basically an M10A1 GMC (an M4A3 Medium with an M10 GMC turret; none saw combat) with a new turret and a 90mm gun derived from the M1 towed AA weapon. Because of its potent gun the M36 was the most successful of the three main U.S. TD. Like the others however, it was all too often expected to double as a tank—a task for which it was not well suited due to its thinner armor, weak MG FP, and open top. As the massive muzzle blast of the 90 mm gun obscured the crew's vision and reduced the rate of fire, a double-baffle muzzle brake was fitted to all vehicles after the first 600, beginning in early November 1944. A proper folding travel lock better-suited to the 90 mm gun was added to the rear hull at about this time. The gun itself was also modified with a better equilibrator and more powerful elevating mechanism.
Conceived in 1943, the M36 first served in combat in Europe in October 1944, where it partially replaced the M10 tank destroyer. The first 40 M36s did not make it overseas until September 1944, and entered combat in October 1944. The First and Ninth US Armies used M36s to reequip tank destroyer battalions attached to armored divisions. The 703rd Tank Destroyer Battalion began reequipping on 30 September 1944. The M36 was well-liked by its crews, being one of the few armored fighting vehicles available to US forces that could destroy heavy German tanks from a distance. By the end of 1944, seven tank destroyer battalions had converted to the M36. The M36 had mostly replaced the M10 by the end of the war.

asl3d · Post by **asl3d** » Tue Jan 26, 2021 4:23 pm

US Vehicular Pontoon

By 1943, combat engineers faced the need for bridges to bear weights of 35 tons or more. To increase weight bearing capacity, they used bigger floats to add buoyancy. This overcame the capacity limitation, but the larger floats were both more difficult to transport to the crossing site and requiring more and larger trucks in the divisional and corps trains.
A treadway bridge was a multi-section, prefabricated floating steel bridge supported by pontoons carrying two metal tracks (or "tread ways") forming a roadway. Depending on its weight class, the treadway bridge was supported either by heavy inflatable pneumatic pontons or by aluminum-alloy half-pontons. The aluminum half-pontons were 9.02 m long overall, 2.11 m wide at the gunwales, and 1.02 m deep except at the bow where the gunwale was raised. The gunwales were 2.03 m center-to-center. At 150 mm freeboard, the half-ponton has a displacement of 12,000 kg. The sides and bow of the half-ponton sloped inward, permitting two or more to be nested for transporting or storing.
A treadway bridge could be built of floating spans or fixed spans. An M2 treadway bridge was designed to carry artillery, heavy duty trucks, and medium tanks up to 37 tons. This could be of any length, and was what was used over major river obstacles such as the Rhine and Moselle. Doctrine stated that it would take 5 1/2 hours to place a 362-foot section of M2 treadway during daylight and 7 1/2 hours at night. Pergrin says that in practise 50 ft/hour of treadway construction was expected, which is a little slower than the speed specified by doctrine.
A Heavy Ponton Bridge Battalion was provided with equipage required to provide stream crossing for heavy military vehicles that could not be supported by a light ponton bridge. The Battalion had two lettered companies of two bridge platoons each. Each platoon was equipped with one unit of heavy ponton equipage. The battalion was an organic unit of army and higher echelons. The M1940 could carry up to 23 tons. The M1 Treadway Bridge could support up to 18 tons. The roadway, made of steel, could carry up to 45 tons, while the center section made of 100 mm thick plywood could carry up to 27 tons. The wider, heavier tanks used the outside steel treadway while the narrower, lighter jeeps and trucks drove across the bridge with one wheel in the steel treadway and the other on the plywood.
An Engineer Treadway Bridge Company consisted of company headquarters and two bridge platoons. It was an organic unit of the armored force, and normally was attached to an Armored Engineer Battalion. Each bridge platoon transported one unit of steel treadway bridge equipage for construction of ferries and bridges in river-crossing operations of the armored division. Stream-crossing equipment included utility powerboats, pneumatic floats, and two units of steel treadway bridge equipment, each of which allowed the engineers to build a floating bridge about 160 m in length.