By 1960, the M47 Patton old 90 mm was still a potent weapon. Pending replacement in the Bundeswehr, it was decided to reuse it in German-made tank-hunters. General design tended to be close to the very successful ww2 era Jagdpanzer IV. Specifications were made and transmitted to three manufacturers, the German Hanomag and Henschel and Swiss MOWAG which produced prototypes. After trials, only Hanomag and Henschel were retained for pre-production.
They built another pair of prototypes, equipped with the German-built Rheinmetall BK 90/L40, derived from the US patented antitank gun. Development goes on until 1965 when the Kanonenjagdpanzer (sometimes followed by 4 5 or “90”), also called Jagdpanzer Kanone 90, was accepted for service in the Bundeswehr.
Basically, the KnJgPz-90 was indeed closely based on the wartime tank-hunter, which was derived from the Panzer IV. However, this was only superficially as the sloped armor was mostly copied from it. Everything else, from the chassis, suspensions, engine and transmission, armament and targeting devices, fire control, etc. were genuine. The hull was longer, but narrower and lighter than the original vehicle. The frontal armor was not 80 but 50 mm in thickness (still around a 80 mm equivalent) also on the sides, and 10 mm on the bottom and roof, engine deck and rear plating. The mantlet allowed a 15° traverse and -8° to +15° elevation/depression.
The hull upper armor was stepped on the rear engine compartment. The driver sat on the right, with a hatch above him, and there was a secondary periscope at the left of the gun. There was a secondary hatch behind the driver, and a commander cupola to the rear, left of the fighting compartment. The drivetrain consisted of five doubled-roadwheels independently sprung on torsion arms, with three return rollers, rear drive sprocket and front idler.
One machine-gun was coaxial in the mantlet, the other was externally mounted on the second hatch ring. The main gun carried 51 rounds 4000 were stored for both 7.62 mm machine-guns. The KnJgPz-90 was protected NBC and fitted with infrared vision and targeting system.
The 770 order was placed between Henschel (385) and Hanomag (385) delivered between 1965 and 1967. The Belgian Army received 80 slightly modified Kanonenjagdpanzer in 1975, which served until the late 1980s.
The Kanonenjagdpanzer 90 in service
This vehicle was considered a success, due to its low profile and superior mobility, compared to the high profile of the M47/48 Patton series. However, by the time USSR unveiled its T-64 and later T-72, the KnJgPz-90 was considered obsolete. The manufacturers proposed it was up-gunned with the latest 105 mm, but in 1983 it was decided to convert 163 of these as Raketenjagdpanzer Jaguar 2 anti-tank guided missile carriers, firing TOW wire-guided missiles, far more effective.
These vehicles also received extra modifications like spaced and perforated armor. A few others were derived as Beobachtungspanzer (without the main gun) to guide mortar units. The regular vehicles were gradually phased and put in reserve. The last were in active commission with the Heimatschutztruppe by 1990.
Jagdpanzerkanone 90 specifications
|Dimensions||6,24 (8,75 oa) x 2,98 x 2,9 m (20ft6 x 9ft9 x 6ft1)|
|Total weight, battle ready||27.5 tons ( ibs)|
|Crew||4 (Driver, commander, gunner, loader)|
|Propulsion||MTU MB-837 V8 diesel 29.4 l 500 hp (368 kW)|
|Suspension||Independant torsion bars|
|Speed (road)||70 kph (43,5 mph)|
|Range||385 km (239 mi)|
|Armament||Rheinmetall BK 90/L40 90mm|
2 x 7.62mm MG3 machine guns
|Armor||12.7 mm front and sides (0.5 in)|
|Total production||770 in 1965-67.|