The M915 is a tractor unit used for line haul missions by the United States Army. Designed for use on improved roads, it does not have a driven front axle.
| M915 | |
|---|---|
 A M915A5 | |
| Type | 6x4 semi-tractor |
| Place of origin | United States |
| Production history | |
| Designer | Crane Carrier Co. (M915) Freightliner (M915A2) |
| Manufacturer | AM General (M915, M915A1) Freightliner (M915A2 and later) |
| Specifications (M915A2[1]) | |
| Mass | 18,680 lb (8,470 kg) (empty) |
| Length | 22 ft 11 in (6.99 m) |
| Width | 8 ft 2 in (2.49 m) |
| Height | 9 ft 11 in (3.02 m) |
| Engine | Detroit Diesel DDEC II 400 hp (300 kW) |
| Transmission | 4-speed automatic |
| Suspension | Beam axles on leaf springs |
Operational range | 300 miles (480 km) |
| Maximum speed | 55 mph (89 km/h) |
History edit
The M915 is the namesake and basis of a tactical truck series, although it is not tactical itself. It is a commercial type conventional 6x4 rear wheel drive 14-ton semi-tractor designed for use on improved roads. A powered front axle and other tactical equipment are not needed for this role, allowing a lighter and simpler truck. It shares the engine, transmission, cab, and some components of the other trucks in the series.[2]
The more specialized trucks in the series are the M916 6x6 all wheel drive 14-Ton Light Equipment Transporter (LET) tractor with rear winch; M917 8x6 20-ton, 12 cubic yard Dump Truck; M918 6x6 22.5-ton, 1,500 gallon Bituminous Distributor; M919 8x6 22.5-ton, 8 cubic yard Concrete Mixer; and M920 8x6 20-ton Medium Equipment Transporter (MET) tractor with rear winch, all of which are employed in Engineer Combat Support and Construction units.
The M915 and follow on M915A1 were a Crane Carrier Company design based on CCC's Centaur commercial tractor, built under contract by AM General between 1978 and 1982. The 1990 -A2 upgrade was a completely different truck: a Freightliner Trucks design with a different engine and transmission, hood and cab. Older models were upgraded to -A4 standard with a new cab and frame that used the original truck's components. Starting in 2009 M915A3s were upgraded to the armored -A5 standard.
Engine and driveline edit
The M915 has a 855 cu in (14.0 L) Cummins NTC 400 developing 400 hp (300 kW) at 2100rpm and 1,150 lbf⋅ft (1,559 N⋅m) of torque at 1500rpm. The M915A2 had a 775 cu in (12.7 L) Detroit Diesel Series 60 DDEC II developing 400 hp (300 kW) at 2100rpm and 1,400 lbf⋅ft (1,898 N⋅m) of torque at 1200rpm. Both are turbocharged inline 6 cylinder 4-stroke diesel engine, both engines are intercooled. The Cummins uses a water to air after-cooler while the Series 60 uses an air to air after-cooler.[3][4]
The M915 has a Caterpillar 16 speed semi-automatic transmission, the M915A2 Allison HT-470 4-speed automatic.[4][5]
Chassis edit
A conventional ladder frame has a front steering axle with a 12,000 lb (5,400 kg) weight rating and tandem rear axles with a 40,000 lb (18,000 kg) weight rating. The truck can have a maximum weight of 52,000 lb (24,000 kg), including a 30,000 lb (14,000 kg) load. The total weight rating of the truck and trailer is 105,000 lb (48,000 kg).[6][7]
A Holland commercial type sliding fifth wheel could carry 30,000 lb (14,000 kg).[8] It towed the M871 22+1⁄2-ton (20,400 kg) 2 axle flatbed, the M872 34-ton (30,800 kg) 3 axle flatbed, and the M1067.[9]
Operators edit
Gallery edit
-
M915 -
M915A5 -
M915A3
References edit
- ^ TM 9-2320-363-10 Operator's Manual for Truck, Trator, Line Haul: 52,000 GVWR, 6x4, M915A2 (NSN 2320-01-272-502) (and others). US Dept. of the Army. 1997. pp. 1–5, 1-16 to 1-19, 2–28.
- ^ TM 9-2320-363-10 (1997), p. 1-15.
- ^ TM 9-2320-273-10 Operators Manual Truck Tractor, Line Haul, 50,000 GVWR, 6x4, M915 (and others). US Dept of the Army. 1980. pp. 1-16 and 1-17.
- ^ a b TM 9-2320-363-10 (1997), pp. 1–17, 1–18.
- ^ TM 9-2320-273-10 (1980), p. 1-19.
- ^ TM 9-2320-363-10 (1997), p. 1-16.
- ^ TM 9-2320-363-20-1 Unit Maintenance Manual for Truck, Trator, Line Haul: 52,000 GVWR, 6x4, M915A2 (NSN 2320-01-272-5029) (and others), US Dept. of the Army, 1992, p. 1–13
- ^ TM 9-2320-363-10 (1997), p. 1-22, 2-58 to 2-99.
- ^ TM 43-0001-31 Equipment Data Sheets for TACOM Combat and Tactical Equipment. US Dept. of the Army. 1985. pp. 6–76, 6–80.
External links edit
- M915 Technical Manuals M915 Technical Library
- M915 Line-Haul Tractor - Olive-Drab