M-47 AND M-60 AVLBS:
DESCRIPTION :
The Military Vehicle Research and Development Establishment at Rawalpindi, has developed an Armoured Vehicle-Launched Bridge (AVLB) based on the turretless chassis of an
M47M tank for the Pakistan Ministry of Defence. The project has been described as a step towards indigenous development and self-reliance. For details of the original M47M tank refer to Jane's Armour and Artillery 1994-95 page 140. The bridge-launching mechanism is installed on the hull of the turretless M47M and is used to launch an aluminium alloy folding scissors bridge with a maximum span of 21.4 m. The bridge has a maximum clear span of 20.3 m. The vehicle has a crew of two, a driver and a commander/operator who uses 13 hydraulic cylinders to launch the bridge in about 3 minutes. Power for the hydraulic system is provided by the M47M launch vehicle's main engine.
The bridge-launching sequence commences with the main launching cylinder lifting the main launching beam from its transport position. When the bridge reaches an angle of 45° the bridge unloading cylinder is operated and starts to retract. As it retracts it pulls a set of two steel ropes, passing over a system of pulleys and joined to the further part of the bridge. This initiates the bridge unfolding sequence. The travel of the main launching cylinder and the bridge-operating cylinder continues until the nearest part of the bridge rests on the ground in front of the launcher. In this position the launching cylinders block the movement of the launching frame and the bridge is pushed further by auxiliary cylinders. The fulcrum of operation shifts and the operation of the bridge-opening cylinders continues until the bridge is fully open. The bridge is then lowered into position by the main operating cylinder. At this point the operator actuates three unlocking cylinders disengaging the launching beam from the bridge. A mechanical lock is opened at the same time allowing the launching vehicle to move away from the bridge. The bridge is recovered in the reverse sequence. If the launch vehicle engine or the hydraulic pumps fail, there is provision for manual launching of the bridge. The M47M launcher can also be used to lay a short single-span bridge. This bridge is one half of the folding 21.4 m bridge fitted with an extra set of folding ramps. No details are available regarding this variant but it is assumed that it is launched in the same manner and sequence as the full-size folding bridge.
SPECIFICATIONS :
AVLB
Crew: 2
Weight: 54,000 kg
Width: 4 m
Height: 3.83 m
Bridge
Weight: 9,800 kg
Max span of bridge: 21.4 m
Max clear span: 20.3 m
Bridge width: 4 m
Distance between treadways: 0.96 m
STATUS : Prototype.
COMPANY NAME : Military Vehicle Research and Development Establishment
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
??? we only wanted to split your country so that we do not have to face threats from both sides of the border and by god's grace..we r successful
we r talking about 1965 here dumbo.
