Pacific, Heroes and Leaders mod Expansion

[asl3d]

M12 155 mm Gun

When the war began in Europe in 1940, it became clear, that the USA would be likely to take part in it, early or late. It was thus decided to develop a self-propelled gun to provide more mobility to field artillery. The choice of the engineers was made on the French gun of 155 mm of the 1st world war. This gun was to be installed on the chassis of the medium tank M3 Lee.
The T6 prototype was finalized and tested during the summer 1941 successfully and it was approved for the production as M12 155 mm Howitzer Motor Carriage. The gun of 155 mm was installed to the back of the completely worked over again superstructure, just behind the engine moved towards the center.
A total of 100 specimens were manufactured in 1942-1943 by Baldwin Locomotive Works. Because of mechanical difficulties and doubt as for the reliability and the utility of this weapon, this first series was not followed by others.
In preparation of the campaign of Western Europe, 75 specimens were modernized in 1944 to be sent there. These specimens had bogies of the M4 type, not door on the right side of the cabin for the driver and a small shield for the howitzer.
Because of the lack of place in the compartment of combat to install all howitzer crewmen and an acceptable reserve of ammunition. A special version of M12 was created to cure this problem.
M30 was identical to M12, if not that its howitzer of 155 mm was removed. The station of combat thus released could accomodate 40 projectiles of 155 mm as well as two howitzer crewmen who could not find place in M12. M30 was equipped with hatchback to contribute to the loading of the ammunition and of a circular for a .50cal machine-gun (12.7 mm). There was a M30 for each M12.

[asl3d]

LVT-2 Water Buffalo

Because of premature wear of the tracks and suspension on the LVT-1 Alligator, it was thus necessary to develop a new vehicle more resistant to sea water corrosion. Work begins during the summer 1941 in agreement between FMC and Navy's Bureau of Ships. The prototype was supplemented December 1941 and subjected to various intensive tests and evaluations. The new model was called LVT-2 Water Buffalo.
The principal modification compared to the LVT-1 is on the level of the suspension and the tracks. The suspension of the rigid type of the LVT-1 was replaced on the LVT-2 by a suspension of the type Torsilatic (springs of torsion). This suspension comprised each side a front sprocket-wheel (37 teeth), a back idler (33 teeth) adjustable, 11 independent road wheels and two return rollers. The suspension devices were articulated around a broad box in the shape of trapezoid. The new tracks assembled on the LVT-2 are completely hermetic to sea salt and sand. They in are equipped with grousers (blades) in the shape of "W". Old diagonal grousers caused a side pressure and a wear in water.
The armament comprised a machine-gun of 12.7 mm (.50cal) and three machine-guns of 7.62 mm (.30cal) assembled on the roof of the cabin or the walls of cargo-space. This arrangement could vary according to the preferences of the crews and field realities.
Like the LVT-1, the LVT-2 was divided into three parts: the cockpit accomodating the three men of crew, cargo-space which can accomodate 24 passengers or 3 tons of material and the engine compartment. The final shape of the hull required the test of 100 different versions. The superstructure of the cabin is much smaller and lower than that of the LVT-1, it does not cover any more entirety the front part of the vehicle. The sides of this one were tilted and either vertical. It comprised two broad windows of vision in front and two smaller on the sides. The LVT-2 was larger than the LVT-1, it was 7.95 m long, 3.25 m broad, 2.50 m in height and weighed 14 tons. Like the LVT-1, the LVT-2 was not armoured.

[asl3d]

LVT(A)-2 Water Buffalo

LVT(A)-2 was developed starting from LVT-2 in order to provide more protection to the crew. This machine is the only Amtrac to receive designation (A) or Armored. LVT(A)-1, LVT(A)-4 and LVT(A)-5were all Amtanks and were equipped with turrets and guns. This conversion known at the beginning under the designation of T33 was developed at the request of the Army which wished to armour Amtracs in the current of 1942. At that time LVT-2 and LVT(A)-1 were under development and one simply decided to equip LVT-2 with certain elements of LVT(A)-1. In fact except for the cabin LVT(A)-2 did not differ quasi from LVT-2.
The armament comprised a machine-gun of 12.7 mm (.50cal) and three machine-guns of 7.62 mm (.30cal) assembled on the roof of the cabin or on the walls of cargo-space. This arrangement could vary according to the preferences of the crews and field realities.
Like the LVT-2, the LVT(A)-2 was divided into three parts: the cockpit accomodating the three men of crew, cargo-space which can accomodate 24 passengers or 3 tons of material, and the engine compartment accomodated always the same engine as the M3A1 Light Tank, the Continental W-670-9A (gasoline) of 7 cylinders developing 250 to 262 hp. This engine made it possible the Buffalo Toilets to reach the 30 km/h on ground and the 12 km/h in water. The LVT(A)-2 had an autonomy of 240 km on ground and 80 km in water. The driveshaft traversed all cargo-space in length to join the transmission of the Synchromesh type (synchronized) comprising 6 speeds (5/1). The power was transmitted to the front sprocket-wheels. On the LVT-2, the rear deck was composed of three plates whose central plate (broadest) had a grid of ventilation assembled on hinges. However on the LVT(A)-2 the grid was removed and replaced by an armoured plate. The back plate of the hull did not comprise any opening if not the exhaust ports. Another change, fuel tanks with automatic obturation were installed to prevent any risk of fire and explosion.
The production of LVT(A)-2 began in 1943 and and continued in 1944. A total of 450 specimens only were manufactured by the FMC, Borg-Warner Corp. and Roebling, all delivered to the Ground Army. In March 1944, kits usable on the ground will be provided (armour-plates) and will be welded onto basic LVT-2 used as amphibious vehicles of assault. Approximately 1000 LVT-2s were thus converted but were never called LVT(A)-2.

[asl3d]

LVT-3 Bushmaster

During the development of the LVTs, Navy' S Bureau of Ships requested the assistance of the Morse Claim Company (Borg-Warner Corp.). The latter studied the LVT-1 and decided to create a very new design in order to solve the defects of this one. The development of the new model immediately began (February 1942) and the first pilot model was supplemented in August 1942 after only 6 months of work. The LVT-3 Model A was a combination of new ideas based on the original Alligator and the LVT-1. The suspension of the Torsilastic type (torsion springs) comprised each side a front sprocket-wheel, 11 independent road wheels (bigger size than those of the LVT-1), two return rollers and an adjustable back sprocket-wheel. The front sprocket-wheels were coupled with an entirely automatic transmission. The external walls of Model A out of corrugated steel had a higher total strength and a lighter weight. But one of the most remarkable innovations is the possible conversion of this amphibious carrier in amphibious tank by the installation of a turret of light tank M3 Stuart. However the new design did not have enough innovations compared to the new LVT-2 of FMC. Let us note that the idea to mount the turret of M3 Light Tank was taken up by FMC for its Amtank LVT(A)-1.
The armament officially made up of a heavy machine gun of 12.7 mm (.50cal) and two machine-guns of 7.62 mm (.30cal) could vary according to preferences of the crew. LVT-3 was not armoured. Model B was standardized as LVT-3. Although comprising elements of LVT-2 and of LVT-4, LVT-3 resembled to LVT-1 more. Indeed the very tilted nose was easily recognizable compared to the very pointed noses of LVT-2 and LVT-4. The top of the cabin (provided with four windows of vision) occupied all the front part of the vehicle like on the LVT-1. LVT-3 was a very successful design, weighing a half thunders of less than LVT-4 and being able to transport 1360 kg more. It was however slower. The firms Graham-Paige and Borg-Warner manufactured 2964 in 1943-45 of them.

[asl3d]

LVT-4 Water Buffalo

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. 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.
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. This total was divided between the Ground Army (6083), the Marines (1765) and the allied countries (503).

[asl3d]

LVT(A)-1 early

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. It acted either of an amphibious carrier but of a genuine amphibious tank or Amtank. The Marines contacted FMC, which developed its LVT-2 Water Buffalo whereas Borg-Warner developed a similar convertible vehicle being able to accomodate a turret of M3 Stuart Light Tank. However the design of Borg-Warner resembled too much to the Alligator of Roebling and the Navy, preferred the LVT-2 of FMC to it. It was thus the latter which was selected as bases for this first Amtank.
The prototype had a cabin rather different from that of the LVT-2 with armoured ports of vision and two machine-guns of 7.62 mm mouunted in front of the cabin. Two trap doors of access with episcopes were assembled on hinges on the roof of the cabin. For the models of production one recovered the cabin of the LVT-2. However all the windows of vision were removed, except that of the driver who was equipped with an armoured shutter. This cabin did not have a machine-gun, which the experiment of the combat showed being a defect, because frontal local defense against the enemy infantrymen was assured only by the coaxial machine-gun the turret, in so far as this one is pointed in the good direction. On the last models a machine-gun of 7.92 mm (.30cal) mounted on ball was assembled to the right of the window of vision of the driver. This cabin was also surmounted by two trap doors with episcopes assembled on hinges.
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.

[asl3d]

LVT(A)-1 late

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 (mounted on the right trap door and just in front of the latter) and a fixed episcope (mounted in front of the trap door of left). 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 of Amtank 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. At the beginning the machine gunners were protected only in front by the shield from their machine-gun and the partial shield of the circular. Thereafter a broad semicircular shield will come to protect the sides and the back from the station of shooting.

[CHINCHIN]

I'm looking forward to seeing the units and the scenarios!

Will they be there soon?

[asl3d]

The units of the Imperial Army Japan are almost finished. Only some vehicles are missing. Right now I'm going to start posting these units.

The Marines and the rest of the US material from the Pacific and Europe are missing.

The scenarios I have not started. First I have to define the new terrain and its rules. It's fast but it has to be done.

Patience.

Regards,

[asl3d]

LVT_A-1 M24 turret

The Army required in June 1944, that the turret of LVT(A)-1 have replaced by that of M24 Chaffee Light Tank in order to increase the fire power of the vehicle. To compensate the weight increase, the transmission and the suspension were reinforced. To accomodate the turret of M24, the compartment of combat was also modified because the circular of this one was broader. The turret was assembled to the back of the compartment of combat. There was no station of machine-gun to the back. The tests showed its instability in water.
The turret which did not have a well of turret, vaguely had the shape of a river flat stone. The sides were prolonged to the back to form a projection which accomodated the radio station of the tank which one sees the antenna on the left side. One reached the turret via the cupola of commander located at the center-left of the roof: the latter were equipped with 6 armoured panes for fixed episcopes and with a circular trap door assembled on hinge equipped with a fixed episcope, or via a trap door in the shape of parallelogram mounted on hinges located at the center-right of the roof. The turret still had an opening protected by an armoured valve on the right side for the evacuation of the casings. The turret accomodated the last three men of crew: the commander, sitted in the back-left corner, the gunner sitting in the front-left corner and the loader sitting in the back-right corner. The turret was hydraulically-operated but could be operated manually. Separately the episcopes of the cupola of the commander, the turret was still equipped with a fixed episcope to the front-left for the use of the gunner. This turret was armed with the gun of 75 mm M6 L/39 on M34 mounting with a coaxial .30cal machine-gun (7.62 mm) and a monocular sight tube. This gun is a version reduced of M3 assembled on M4 Sherman intended for the origin to the bomber B-25 Mitchell. M6 weighed half less than M3 and had the same performances. M6 in was equipped more with a concentric system of recoil, which got more espace in the interior of the turret. Armament was supplemented by an anti-aircraft .50cal machine-gun (12.7 mm) mounted on a tripod mounting to the back of the turret.
One thought to regulate instability in water, by reducing the length of the vehicle from 20 to 23 cm and by reducing the weight of the turret and by moving this one forwards (5 cm) for a better balance. However these modifications were never made because of the end of the war, and the project was finally abandoned. However this design was very promising, and got for Amtank a fire power ever reached up to now.

[asl3d]

LVT(A)-4 early

LVT(A)-1 was developed to provide a support fire to the amphibious waves of assault during the first critical hours before the light and medium tanks can be landed. However these Amtanks armed with the gun of 37 mm M6 met only very few Japanese tanks in the reconquest of the Pacific Islands. On the other hand the Japanese transformed those into fortresses constellated with strengthened works. The gun of 37 mm was completely impotent to bore bunkers. Amtank equipped with a more powerful armament was thus necessary. It was thus determined to replace the turret of M3 Light Tank by that of M8 Howitzer Motor Carriage armed with the howitzer of 75 mm. 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.
This turret was assembled on modified LVT-2 and armoured, like for the turret of M3 Stuart. 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. As for first LVT(A)-1s, 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.
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. Only 50 LVT(A)-4s were yielded to the allied countries. Perfectly able to destroy the Japanese strengthened places and the rare Japanese tanks met, the LVT(A)-4 however suffered from the lack of protection gotten to the crew of the open turret. This one was indeed exposed to the shooting of the Japanese snippers. The first models in more were hardly armed with only one machine-gun against the Japanese kamikazes infantrymen.

[asl3d]

LVT(A)-4 late

This turret was assembled on modified LVT-2 and armoured, like for the turret of M3 Stuart. 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. As for first LVT(A)-1s, 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.
To create a closed compartment of combat, the cabin was prolonged over the cargo-space. Contrary to those of the LVT(A)-1, 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 inherited of M8 HMC assembled on the first LVT(A)-4 was armed with an howitzer of 75 mm M3 on M7 mounting. This weapon fired high-explosive shells at low initial speed but to high devastator capacities. 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°.
A first solution was brought while installing a machine-gun of 7.62 mm (.30cal) in front of the cabin which could take responsibility for the frontal brought closer defense. However for more effectiveness, 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.

[asl3d]

LVT(A)-5

he LVT(A)-5 is an official version of the LVT(A)-4 taking all the modifications made on the "Marianas Model' ' of the LVT(A)-4: a machine-gun of 7.62 mm (.30cal) assembled on ball in front of the cabin and two machine-guns of 7.62 mm assembled on pivot on the sides of the turret, in the place of the machine-gun of 12.7 mm (.50cal).
The LVT(A)-5 had in more one gyrostabilisator for the howitzer of 75 mm M3 which enabled him to make fire moving and in water, a counterweight was also assembled on the tube. The turret was also equipped with a hydraulic system of rotation and a well of turret.
A total of 269 LVT(A)-5s were produced by FMC at Riverside (California) in 1945 before the end of the war puts a term at the production.

[asl3d]

M2 Halftrack Car

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. Important fact, the German halftracks distributed the power of their engine only on the two tracked trains only whereas the US models also distributed this one on the nose wheeled train. The steering on the American models was made with the means of the nose wheels then that the models German also used their tracked trains while exploiting the speed of the sprocket-wheels or while slowing down on one or on the other.
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). In September 1940 the prototype was accepted for the production and 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.
M2 was finalized to be used as vehicle of reconnaissance or like artillery tractor. 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.

[asl3d]

M2A1 Halftrack Car

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. Important fact, the German halftracks distributed the power of their engine only on the two tracked trains only whereas the US models also distributed this one on the nose wheeled train. The steering on the American models was made with the means of the nose wheels then that the models German also used their tracked trains while exploiting the speed of the sprocket-wheels or while slowing down on one or on the other.
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).
To improve its protection counters the air raids or terrestrial, M2 was equipped on the right side with the cabin with a circular mounting M45 "Pulpit" for machine-gun of 12.7 mm (.50cal) Browning M2HB. This new model was baptized M2A1 Halftrack Car. Between October 1943 and March 1944, 1643 M2A1 were produced (including 1266 M2s converted). The rail making the turn of the compartment of combat was removed, it was not practical in condition of combat. Three receptacles for machine-guns .30cal were installed in its place (two on the sides and one to the back).

[asl3d]

M3 Halftrack Car

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. The US Cavalry wished to replace these 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 (inherited T9 Halftrack Truck) in the place of its rear wheel-axle unit. This model was baptized T7. Cependant, T7 was under-motorized and the nose gear was used only for the steering. In September 1940, this experimental vehicle was accepted for the production under the name of M2 Halftrack Car. The Infantry asked for its use a 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.
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. M2 and the M2A1 equipped also various allied countries like Great Britain, the USSR or France.
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.

[asl3d]

M3A1 Halftrack Personnel Carrier

M2 Halftrack Car which had been conceived for the Cavalry and of the reconnaissance missions, could accomodate only 10 men, crew included, which was insufficient to play a part of transport of troop because a section of infantery was made up of 10 men. Moreover because of the rail for .30cal machine-guns making the circumference of the compartment of troop, M2 did not have back access doors to charge or discharge its passengers. A version longer and better adapted to this kind of mission was thus carried out. A total of 12391 specimens were produced by White Motor, Autocar, Diamond T. 108 M3 75 mm GMC were converted.
In fact, M3 very resembled to M2 if not that the hull was prolonged towards the back of a few centimetres, and that because of the removal of the rail, a door could be installed to the back. The trunks present behind the seats of the pilots on M2 were also removed to install additional seats. M3 comprised 13 seats now: two seats for the pilot and the copilot in the cockpit, the seat of the commander just behind them and the seats of the infantrymen laid out by 5 on each side of the compartment of troop. The fuel tanks were moved forwards, in the place of the trunks of arrangement. Sites of arrangement were located below the seats and racks for rifles or carabines were installed behind the backs of the seats to the back of the compartment. Because of the removal of the rail, 3 receptacles for .30cal machine-guns (7.62 mm) were installed on the circumference of the station of combat coming to reinforce the pedestal accomodating a .30cal or .50cal (12.7 mm) machine-gun. As for M2, the front fender of the M3 was equipped with a roller helping the vehicle to be extracted from difficult grounds. Racks of mines traversed all the length on the sides of the compartment of troop. If not, the suspension, the engine and the performances were identical to M2, as well as the shielding.

[asl3d]

M3A2 Halftrack Personnel Carrier

As for M2, the provision of the armament of M3 was considered to be unsuited to the conditions of combat and the pedestal was replaced by a circular mounting M49 installed to the top of the right part of the cabin as on the M2A1. This mounting accomodated an anti-aircraft .50cal machine-gun. This model was called M3A1 Halftrack Personnel Carrier and started production at the end of 1943. Diamond T, White and Autocar produced T 2862 specimens of the M3A1 in 1943-1944. 2209 M3 were converted into M3A1.
In order to simplify, the production of the halftracks, Ordnance Department decided at the beginning of 1943 to amalgamate M2 and M3 in only one model. The T29 prototype was tested in spring 1943 and was accepted for the production in October as M3A2 Halftrack Personnel Carrier. At that time, however, the need for half-tracked vehicles was less important and this model was never manufactured in mass. The only innovation of this model copied on the M3A1, was its armoured circular mounting for the anti-aircraft .50cal machine-gun. Still let us note the retractable racks installed to the back of the vehicle.

[asl3d]

M5 Halftrack Personnel Carrier

From the beginning of the Second World War, the Americans were the principal suppliers of weapons and material of the allied forces because of their fantastic industrial capacities and the absence of bombardment on their territory. The same applies to the halftracks, however the firms up to now charged to produce them (White, Autocar and Diamond T) could not assume a such increase in the production and a fourth firm was recruited, International Harvester Company.
The models which were produced by this firm, present some differences with the models of the other firms. Indeed, modifications had been brought in the specifications of the half-tracked vehicles. One of most important is the replacement of the tempered steel plates by rolled homogeneous steel plates. With these plates, the shielding was 7.9 mm instead of 6.4 mm. The thickness of the shutter of the windshield was now 15.9 mm instead of 13. These plates were not any more bolted but were welded between them. The increase in the weight because of the shielding more raised, somewhat decreased the performances on the maximum speed level (68 km/h instead of 72 km/h). Harvester also includes there elements of its manufacture like engine RED-450-B (gasoline) of 6 cyl. developing 143 hp to 2700rpm, a new front axle, a new box of transfer and a new transmission (Spicer 1856) comprising 5 speeds (4/1). Harvester proposed two models, one of both, the M3E2 (based on M3) will become M5 Halftrack Personnel Carrier. To outside, the differences between M5 and M3 related to the mudguards of the nose gear which on M5 were flat and not rounded as on M3 (and M2), the corners were ounded to the back. The interior of M5 was arranged same manner that that of M3 and could accomodate 13 men. M5 was produced only by Harvester to 4625 specimens in 1942-1944.
As for M2 and M3, the armament of M5 was improved by the adoption of a circular mounting M49 installed to the top of the right part of the cabin as on the M2A1 and the M3A1. This mounting accomodated an anti-aircraft .50cal machine-gun. This model was called M5A1 Halftrack Personnel Carrier and was produced to 2959 specimens by Harvester in 1943-1944. In order to simplify, the production of the halftracks, Ordnance Department decided at the beginning of 1943 to amalgamate M5 and the M5A1 in only one model. The T31 prototype was accepted for the production in as M5A2 Halftrack Personnel Carrier. At that time, however, the need for half-tracked vehicles was less significant and this model was never manufactured in mass.

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M9 Halftrack Car

To increase the production of the halftracks to equip the allied countries of the USA, a fourth firm was contacted, International Harvester Company. This firm realized two basic models fulfilling the same functions as M2 Halftrack Car and M3 Halftrack Personnel Carrier. One of both, M5 was the equivalent of M3. The other models, the M2E5 was the equivalent of M2. The M2E5 standarized as M9 Halftrack Car, started production in 1943 and was produced to 2026 specimens.
M9 was identical to M5, except for interior arrangement, with if not it had same dimensions, and had a shielding made up of rolled homogeneous steel plates with a thickness of 7.9 mm (15.9 mm for the shutter of the windshield), welded between them. The increase in the weight because of the shielding more raised, somewhat decreased the performances on the maximum speed level (68 km/h instead of 72 km/h). M9 was also equipped with engine RED-450-B (gasoline) of 6 cyl. developing 143 hp to 2700 rpm, a new front axle, a new box of transfer and a new transmission (Spicer 1856) comprising 5 speeds (4/1). M9 was also equipped with flat mudguards for the nose gear and the back corners were also rounded as on M5. Let us note that M9 (as M5) was equipped with a back door contrary to M2. M9 was intended in theory for reconnaissance missions like M2. M9 because of internal arrangement, could accomodate only 10 men, crew included.
As for M5, the armament of M9 was improved by the adoption of a circular mounting M49 installed with the top of the right part of the cabin as on the M2A1, the M3A1 and the M5A1. This mounting accomodated an anti-aircraft .50cal machine-gun. This model was called M9A1 Halftrack Car and was produced to 1407 specimens by Harvester in 1943. The M9A1 was sometimes equipped with one winch in the place of the roller to the front one.