The BMD-1 can be thought of as a BMP intended for airborne troops. The vehicle therefore must be lighter and smaller in order to meet airdrop weight requirements (the BMD-1 is secured to a pallet and parachute-dropped from cargo planes).
| BMD-1 | |
|---|---|
| Type | Airborne Amphibious Tracked Infantry Fighting Vehicle |
| Place of origin |  Soviet Union |
| Service history | |
| In service | 1969 – present |
| Production history | |
| Designer | Volgograd Tractor Plant |
| Designed | 1965–1969 |
| Manufacturer | Volgograd Tractor Plant |
| Produced | 1968 – ? (out of production) |
| Specifications (BMD-1) | |
| Weight | 7.5 tonnes 13.3 tonnes (combat weight) |
| Length | 6.74 m |
| Width | 2.94 m |
| Height | 2.15 m |
| Crew | 2 (driver, gunner) + 4 troopers (including commander and machine gunner) |
| | |
| Armor | cast magnesium alloy 26–33 mm gun mantlet 23 mm at 42° turret front 19 mm at 36° turret side 13 mm at 30° turret rear 6 mm turret top 15 mm at 78° upper hull front 15 mm at 50° lower hull front 10 mm rest of the hull |
| Main armament | 73 mm 2A28 "Grom" low pressure smoothbore short-recoil semi-automatic gun (40 rounds) ATGM launcher (three 9M14M or 9M113 or 9M111M ATGMs) |
| Secondary armament | 7.62 mm PKT coaxial tank machine gun (2,000 rounds) 2×7.62 mm PKT bow tank machine guns (4,000 rounds) |
| Engine | 5D-20 6-cylinder 4-stroke V-shaped liquid cooled 15.9 litre diesel 241 hp (180 kW) at 2,600 rpm |
| Power/weight | 32.1 hp/tonne (24 kW/tonne) 18.1 hp/tonne (13.5 kW/tonne) (loaded with equipment) |
| Suspension | hydraulic independent torsion-bar |
| Ground clearance | Adjustable 100 mm to 450 mm |
| Fuel capacity | 300 l |
| Operational range | 600 km (road) 116 km (water) |
| Speed | 80 km/h (road) 45 km/h (cross country) 10 km/h (swimming) |
BMD-1 has an unconventional layout for an IFV. From front to back of the vehicle the compartments are located in a following formation: steering, fighting, troop and engine. This is because the BMD-1 is based on Ob'yekt 914 which in turn is based on the PT-76 amphibious light tank (refer Prototypes section in the BMP-1 article for details). This meant that transported troops had to mount and dismount the vehicle via the roof hatches which made them an easy target on the battlefield when these actions were performed.
Crew
The crew consist of four soldiers: driver, commander, gunner and bow machine gunner, two of which (commander and machine gunner) are included into number of soldiers carried. The driver's station is located centrally in the front of the vehicle and has hatch that opens raising it and rotating it to the right. The driver is provided with three periscope vision blocks which allow him to view the outer environment when his hatch is closed. The center one can be replaced with a night vision device for use in night and bad visibility conditions or with an extended periscope for swimming with the trim vane erected. On the left hand side of the driver is the commander's station. It is provided with a hatch, one periscope vision block, an outer environment observation device and R-123 radio set for communication. He also fires the left bow machine gun. The right one is operated by a bow machine gun gunner sits on the right hand side of the driver. The gunner's station is located on the left hand side of the turret like in the BMP-1 and has the same equipment (see Gunner's station section in BMP-1 article for details).
Turret
The BMD-1 has the same turret as the BMP-1.
Armament
The vehicle is armed with the 73 mm 2A28 Grom gun and 7.62 mm PKT coaxial tank machine gun. Mounted on the mantlet is the 9S428 ATGM launcher capable of firing 9M14 Malyutka (NATO: AT-3A Sagger A) and 9M14M Malyutka-M (NATO: AT-3B Sagger B) ATGMs (for which the vehicle carries 2 ATGMs in the turret). There are also two 7.62 mm PKT machine guns in fixed mounts, one each in the corners of the bow.
Mobility
Maneuverability
The vehicle is powered by 5D-20 6-cylinder 4-stroke V-shaped liquid cooled 15.9 liter diesel engine developing 270 hp (201 kW) at 2,600 revolutions per minute. The engine drives a manual gearbox with five forward gears and one reverse gear.
The BMD-1 has a maximum road speed of 80 kilometers per hour, reducing to around 45 kilometers per hour off-road and 10 kilometers per hour while swimming.
The BMD-1 can climb 0.8 meter high vertical obstacles, cross 1.6 meter wide trenches and 30% side slopes. It can climb 60% gradients. The BMD-1 has a ground pressure of 0.57 kg/cm².
The 230 mm wide track is driven at the rear and passes over five small evenly spaced road wheels suspended on independent torsion bars. On each side there is an idler wheel at the front, a rear drive sprocket and four track-return rollers. The independent suspension combines a hydraulic system for altering the ground clearance and maintaining the track tension with pneumatic springs, which enables the ground clearance to be altered from 100 mm to 450 mm. Alterable ground clearance allows easier transportation in an airplane.
Amphibious ability
The BMD-1 is fully amphibious, it can swim after switching on the two electric bilge pumps, erecting the two piece trim vane which improves vehicle's stability and displacement in water and prevents the water from flooding the bow of the tank and switching the driver's periscope for a swimming periscope that enables the driver to see over the trim vane. When not in use the trim vane is placed in its laying position in the front of the bow under the barrel of the main gun and serves as additional armour. There is also a manual bilge pump for emergency use. The bilge pumps keep the vehicle afloat even if it is hit, damaged or leaks. In water it is propelled by two hydrojets, one in each side of the hull, with the entrance under the hull and exits at the rear of the hull. The rear exits have lids that can be fully or partially closed, redirecting the water stream to the forward-directed exits at the sides of the hull, thus enabling the vehicle to turn or float reverse, for example, to go left, the left water-jet is covered, to go right, the right water-jet is covered and to make a 180° turn the left water-jet sucks in water and the right water-jet pushes it out.
Air-drop techniques
The vehicle can be transported by An-12, An-22, Il-76, An-124 airplanes and Mi-6 and Mi-26 helicopters.
The BMD was originally dropped under the MKS-350-9 multi-canopy parachute with a descending speed between 15 m/s and 20 m/s. The intention was to drop the vehicle without the crew. This has proved to be very problematic, since the crew frequently landed in a considerable distance from the vehicle and often had trouble finding it. Also the vehicle itself could easily land in a location from which it couldn't be extracted (either because of a lack of suitable equipment or because the location being virtually inaccessible). Several experiments were done in the 1970s in order to find a way to circle around these limitations, these included dropping the BMD with the two key crew members, the driver and gunner, seated inside the vehicle during the descent. The first such test took place in January 1973, and the concept was proved to be valid in a subsequent series of tests.
A rocket parachute, the PRSM-915, was developed to ensure the vehicle's safe landing. To use the parachute, the BMD is first packed onto a special pallet before takeoff. To drop the BMD, a drogue chute is released that initially drags the BMD out of the Il-76 transport plane. Once clear of the plane a single large main chute opens. The deployment of the main chute triggers the deployment of four long rods which hang beneath the pallet. As soon as the rods touch the ground a retrorocket fires, slowing the BMD to a descending speed between 6 m/s and 7 m/s and giving it a relatively soft landing. This system entered service in 1975 and allows a BMD to be relatively safely parachuted with both the driver and the gunner.
An alternative radio location system also exists. Each crew member is given a radio receiver locked onto a transponder in its particular BMD, allowing each BMD crewman to quickly locate his respective vehicle after the airdrop.
Armour protection
The BMD-1's armour is made of cast magnesium alloy, in order to save weight. Combat experience in Afghanistan demonstrated that the armour itself would catch fire and burn fiercely, often killing the crew, when hit with a weapon such as an RPG. Later variants of the BMD had aluminium armour instead.
Armour thickness is 23 mm at 42° on the front of the turret, 19 mm at 36° on the sides of the turret, 13 mm at 30° on the rear of the turret, 6 mm on the rear of the turret, 15 mm on the front of the hull and 10 mm on the rest of the hull. Hull's front armour has two sections: upper and lower. The upper section is angled at 78° while the lower one is angled at 50°. It's resistant to small arms fire and shrapnel.
Troop compartment
Many compromises had to be made to the design in order to save the necessary weight, not least to crew comfort. The BMD-1 has extremely cramped interior space, which is much smaller than that found in the BMP-1 and BMP-2 IFVs. It can carry five infantrymen, including vehicle's commander, bow machine gunner and three soldiers seated behind a turret.
Nevertheless its equipped with periscope vision blocks on the sides and rear of the vehicle. Also there are only three firing ports, two on each side of the hull and one in the rear. As a standard, the vehicle carries following weapons inside the troop compartment: the RPG-7 or RPG-16 shoulder-launched anti-tank rocket propelled grenade launcher which is to be operated by two soldiers, RPKS light machine gun and five AKMS assault rifles. It carries also portable launchers for 9M14M Malyutka missiles (9M111/9M113 missiles in BMD-1P).
