Infanterikanonvagn 91
(Ikv 91)

Infanterikanonvagn 91 (Ikv 91)
Type - Amphibious assault gun
Place of origin - Sweden
Specifications
Mass - 16.3 tonnes
Length - 6.41 m (21 ft 0 in) . 8.85 m (29 ft 0 in) including gun
Width - 3.00 m (9 ft 10 in)
Height - 2.32 m (7 ft 7 in)
Crew - 4
Armor - classified, protects against 20 mm rounds
Main armament - 90 mm KV90S73
Secondary armament - Two 7.62 mm machine gun m/39 . Two Lyran 71 mm flare mortars
Engine - Diesel Volvo Penta model TD 120 A, turbocharged straight six-cylinder; cylinder volume 11.97 litres . 330 hp (250 kW) at 2,200 rpm
Power/weight - 20.2 hp/tonne
Transmission - Allison 4 step automatic
Suspension - Torsion beam suspension
Operational range - 500 km (310 mi)
Maximum speed - 65 km/h (40 mph)

The Infanterikanonvagn 91 ("infantry cannon wagon 91"), Ikv 91, was a high mobility assault gun that was developed to meet the operational requirements of the Swedish Army. It was designed and manufactured by Hägglund and Söner (now Hägglunds Vehicle AB) and employed common components with the Pbv 302 armoured personnel carrier series. The first prototypes of the Ikv 91 were completed in 1969 with production running from 1975 until 1978. The total numbers manufactured were 212.
The number 91 in the name means that it was the first armored vehicle in the Swedish armed forces to feature a cannon in the 9 cm caliber category (91 = 90 mm gun, 1st vehicle in category).
Design
The layout of the Ikv 91 is similar to a large light tank. The Ikv 91 is divided into three main compartments, the driver's station in the forward left hull, the fighting compartment located in the vehicle's midsection, and an engine compartment in the rear hull.
Armament
The main armament consisted of a Bofors KV90S73 90 mm L/54 rifled low pressure gun, firing HEAT and HE rounds. A sloped revolving turret gave protection against projectiles up to 25 mm in calibre. The main gun had an elevation of +15° and depression of -10°. The barrel was equipped with a fume extractor. Additional armament of the Ikv 91 included two 7.62 mm Browning machine guns; one in a coaxial mounting, and the second on a pintle attached to the commander's cupola. Two 71 mm Lyran flare mortars were mounted on the turret along with a set of smoke dischargers (usually 12). The vehicle was equipped with a laser rangefinder, night vision and a computerised fire-control system for increased first-round hit probability. The Ikv 91 fired at a rate of 8 rounds per minute and 59 rounds of 90 mm ammunition were carried internally. The vehicle was also capable of firing while in water, with the water absorbing most of the recoil. The turret itself has a small hatch that can be opened by the loader to eject used cartridge cases to prevent clutter in the vehicle.
With wide tracks and a high power-to-weight ratio, the Ikv 91 offered exceptionally good off-road mobility. The low ground pressure enabled the Ikv 91 to operate through summer taiga and winter snow. The vehicle was fully amphibious with little preparation by the crew. Screens would be erected to stop water from entering the engine and the cabin compartment with a vane to protect from oncoming waves. The vehicle weighed 16.3 tonnes and had a crew of four. It was powered by a Volvo 12 liter, 330 hp, diesel engine. The maximum road speed was 65 kilometres per hour (40 mph) and the range on roads was about 500 kilometres (310 mi).
The Ikv 91 was retired from the Swedish army in the late 1990s - early 2000s due to budget cuts among others and was partly replaced by the Strf 90 combat vehicles and Leopard 2 tanks. When in active duty, the Ikv 91 was assigned to the Swedish infantry brigades, which had one company of 12 vehicles each. The 10th Mechanized Brigade had two companies in the 1980s. In the late 1980s and early 1990s, the 10th Mechanised Brigade had its Ikv 91 replaced with Centurion tanks and in 2000, all Swedish infantry brigades were disbanded. Plans were made to replace its 90 mm gun with a 105 mm gun or even a TOW missile launcher. This was however not followed through in Swedish interests as the role of the Ikv 91 could be filled by new Strv 122 main battle tanks and Strf 90 infantry fighting vehicles.
Besides Swedish interests, a prototype armed with a 105 mm gun was made in 1983 for export, named the Ikv 105. The Ikv 105 was marketed for export and was tested by both India and the United States. The weight was 18 tons and the speed in water was increased to 12 km/h, the main gun was a low recoil fully stabilized version of a high pressure Bofors gun. It had an IR system by SAAB which gave it full night capability. Both the gunner and commander had monitors and could fire the main gun.