| M901A1: General | |||
| Total acceptances | ~1,800 M901 and M901A1 | ||
| Manufacturer | Emerson Electric Co. | Crew |
|
| M901A1: Dimensions | |||
| Combat weight | ~26,000lbs ~12,000kg |
Height, head erected | 134.25" 341.00cm |
| Length | 191.5" 486.4cm |
Gun overhang forward | 0" |
| Width over track shrouds | 105.75" 268.61cm |
Tread | 85.0" 216cm |
| Ground clearance | 17.1" 43.4cm |
Ground pressure, zero penetration | 8.3psi .58kg/cm² |
| M901A1: Armament | |||||
| Type | Mount | Ammunition | Traverse | Max traverse rate | Elevation |
| Twin TOW missile launcher | Targeting head on modified M27 cupola | 10 BGM-71D TOW 2, BGM-71E TOW 2A, or BGM-71F TOW 2B missiles | 360° (manual and hydraulic) |
35°/sec | +35° to -30° (manual and hydraulic) |
| 7.62mm M60 MG | Flexible on cupola mount | 800 rounds | 360° (manual) |
-- | Manual |
| Aiming equipment | |||||
| Daysight/tracker and nightsight AN/TAS-4A for gunner | |||||
| Night vision | |||||
| Infrared periscope M19 for driver, nightsight AN/TAS-4A for gunner | |||||
| M901A1: Armor | ||
| Assembly | ||
| Welding | ||
| Hull | ||
| Rolled 5083/5086 H32 aluminum armor | ||
| Location | Thickness | Angle from vertical |
| Upper front | 1.5" 3.8cm |
45° |
| Lower front | 1.5" 3.8cm |
30° |
| Upper sides | 1.75" 4.45cm |
0° |
| Lower sides | 1.25" 3.18cm |
0° |
| Rear | 1.5" 3.8cm |
9° |
| Ramp | 1.5" 3.8cm |
8° |
| Top | 1.5" 3.8cm |
90° |
| Floor | 1.125" 2.858cm |
90° |
| M901A1: Automotive | |||||
| Engine | General Motors 6V53; 6 cylinder, 2 cycle, vee diesel | ||||
| Horsepower | Gross: 212@2,800rpm | Torque | Gross: 492 ft-lb@1,300rpm | Fuel capacity | 95gal 360L |
| Transmission | Allison TX-100, 3 ranges forward, 1 reverse | ||||
| Steering | DS200 controlled differential, steering levers | ||||
| Brakes | Differential band | ||||
| M901A1: Suspension | ||
| Type | Road wheels | Track return rollers |
| Torsion bar | 5 individually sprung dual/track | Flat track |
| Drive sprockets | Idlers | Shock absorbers | 10-tooth front drive | Dual adjustable at rear of track | On first, second, and last road wheels/track |
| M901A1: Track | |||||||
| T130E1 | |||||||
| Center guide, single pin, steel with detachable rubber pad | |||||||
| Width | 15" 38cm |
Pitch | 6" 15cm |
Shoes/track | Left side: 63 Right side: 64 |
Ground contact length | 105" 267cm |
| T150 | |||||||
| Center guide, double pin, steel with chevron rubber pad | |||||||
| Width | 14.81" 37.62cm |
Pitch | 6" 15cm |
Shoes/track | Left side: 63 Right side: 64 |
Ground contact length | 105" 267cm |
| M901A1: Performance | |||
| Max level road speed | 40mph 64kph |
Max water speed | 3.6mph 5.8kph |
| Max trench | 66" 170cm |
Max grade | 60% |
| Max vertical obstacle | 24" 61cm |
Min turning diameter | 26' 7.9m |
| Max fording depth | Floats | Cruising range | ~300mi, roads ~480km, roads |
The specifications above are for a vehicle based on the M113A2 APC and serving with Mechanized Infantry; M901s were also based on the M113A1, while vehicles in the Armored Cavalry were crewed by 5 men. The M901 conversion involved fitting a "hammerhead" turret on the commander's M27 cupola which contained two TOW missile launchers and the associated targeting and guidance equipment. The missile launcher targeting head was at the end of a pivoting arm which raised the assembly for firing. When stowed, the turret was aimed down and to the rear of the vehicle; this reduced the ITV's height to 115.75" (294.00cm) for M113A2-based vehicles. Twenty seconds were required for erection of the launcher and engagement of the target; after the first missile hit, the second could be launched in 4.25 seconds if the next target was ≤12.5° away. Reloading was accomplished in forty seconds by tilting the launching apparatus back so that the crew could reach the turret through the carrier's rear roof hatch. The vehicle was limited to 5mph (8kph) with the launcher erected. When the ITV was modified to fire the TOW 2 series of missiles, its designation was changed to M901A1. The M901A1 also received an upgrade to the gunner's night sight from the M901's AN/TAS-4. The AN/TAS-4A provided poor visibility missile tracking capability, whereas the daysight was used to track the missiles with the AN/TAS-4. M901A3 was equipped with the RISE improvements of the M113A3.
The various versions of the TOW missile are as follows: BGM-71A from 1970 was the basic version with a 5" (13cm) diameter, 5.4lb (2.4kg) explosive weight warhead and a 3,000m (1.86mi) range. BGM-71B from 1976 extended the range to 3,750m (2.33mi). BGM-71C ITOW (Improved TOW) from 1981 used an improved 5" (13cm) 5.0lb (2.3kg) explosive weight warhead and a 265mm (10.4") long standoff probe which allowed the shaped charge penetrator to assume a more efficient shape before it struck the target. BGM-71D TOW 2 from 1983 had a 6" (15cm) diameter 6.8lb (3.1kg) explosive weight warhead and a 345mm (13.6") long standoff probe, along with a new motor and digital guidance strengthened against countermeasures. BGM-71E TOW 2A from 1987 introduced a precursor charge in the standoff probe to defeat explosive reactive armor. BGM-71F TOW 2B from 1991 was a top-attack weapon using two explosively-formed projectiles that penetrated the roof of armored vehicles. TOW 2B lacked a standoff probe.
