M48 and M60 Armoured Vehicle-Launched Bridges (AVLB)

DEVELOPMENT :

In the 1950s the standard AVLB of the US Army was the M48A2 AVLB. This was an M48 MBT chassis, fitted with a scissors bridge, designed by the US Army Engineer Research and Development Laboratories (now the Belvoir Research, Development and Engineering Center) at Fort Belvoir, Virginia. Production of the M48 was completed in 1959 and from 1963 the chassis of the M60 MBT was used. The chassis of these two vehicles is almost identical, the major difference being the type of engine. The M48, M48A1 and M48A2 were all powered by a 12-cylinder petrol engine which developed between 810 and 825 hp at 2,800 rpm, while the M48A3 was powered by a 12-cylinder diesel (AVDS-1790-2A) engine which developed 750 hp at 2,400 rpm, giving the vehicle an increased operational range. In FY78 the US Army requested $20.9 million to convert 136 M48A1 and M48A2 tanks into M48A5 AVLBs. (These vehicles now have M60 AVLB launcher components and the AVDS-1790-2D engine.) NAPCO Inc of Hopkins, Minnesota, can provide complete AVLB system support including training, technical assistance, special tools packages, spare parts and technical manuals.

DESCRIPTION :

The basic chassis of the M60 AVLB is almost identical to that of the M60 MBT, except that the driver is located aft of his MBT location and accommodation is made in the same area for the commander, since the MBT turret is removed for the AVLB configuration. The engine and transmission are at the rear. Early M48 AVLBs had two turrets, each with a 0.50/12.7 mm Browning M2 HB machine gun, but they were later removed and replaced by two conventional hatch covers. The crew of two consists of the driver and commander. The suspension is of the torsion bar type and consists of six roadwheels with the idler at the front and the drive sprocket at the rear, with three track-return rollers. Hydraulic shock-absorbers are fitted at the first, second and sixth roadwheel stations. The bridge weighs 13,380 kg and is made primarily of aluminium. It is carried folded and launched over the front of the vehicle hydraulically as follows: the AVLB is driven up to the obstacle and halted, the bridge is raised hydraulically into the vertical, unfolded and lowered into place and the launcher detached. The bridge, which weighs 13,290 kg complete, takes 3 minutes to launch and can be recovered from either end. Recovery time is between 10 and 60 minutes depending on the ground conditions. The bridge has an overall length of 19.202 m and can span a gap of up to 18.288 m. Overall bridge width is 3.96 m, 3.81 m of which is usable roadway, with each trackway 1.486 m wide. Its maximum capacity is 54,431 kg.

SPECIFICATIONS :

M60 AVLB
Crew: 2
Weight:
(with bridge) 55,205 kg
(without bridge) 41,730 kg
Length:
(with bridge) 11.28 m
(chassis) 8.648 m
Width:
(with bridge) 4.002 m
(chassis) 3.64 m
Height:
(with bridge) 3.9 m
(without bridge) 3.04 m
Ground clearance: 0.36 m
Track: 2.921 m
Track width: 711 mm
Length of track on ground: 4.235 m
Ground pressure: 0.92 kg/cm{2}
Max speed: (road) 48.28 km/h
Range: 500 km
Fuel capacity: 1,420 litres
Fording: 1.219 m
Gradient: 30%
Vertical obstacle: 0.914 m
Trench: 2.59 m
Engine: Continental AVDS-1790-2A or AVDS-1790-2D 12-cylinder diesel
developing 750 bhp at 2,400 rpm
Transmission: Allison CD-850-6 with 2 forward and 1 reverse ranges
Electrical system: 24 V
Batteries: 6 x 12 V, 100 Ah
Armament: nil
Armour
hull front: 101-120 mm
hull sides front: 76 mm
hull sides and rear: 51 mm
hull top: 57 mm
hull floor: 12.7-63 mm
hull rear: 44 mm

STATUS : Current users are known to include Germany, Israel, Pakistan (M48), Singapore (12 M60), Spain, Taiwan, and the US Army and Marine Corps.

COMPANY NAME : General Dynamics Land Systems Division