Editing Leopard 1 (section)

=== Leopard 1A1 ===
[[File:Leopard1 Bundeswehr 1983.jpg|thumb|A [[West Germany|West German]] [[Bundeswehr|army]] Leopard 1A1A1 with additional spaced armour on the turret and gun mantlet.]]
[[File:2 norwegian Leopard tanks in the snow.jpg|thumb|A [[Norwegian Army]] Leopard 1A1]]

After the last vehicle from the first four production series was delivered, the Bundeswehr initiated an upgrade programme in 1970 to increase the combat effectiveness of its tanks. Known as the '''Leopard A1''' (later '''Leopard 1A1''', after the introduction of the Leopard 2), these tanks received a new gun stabilization system from [[Cadillac Gage]] (full stabilization in both elevation and traverse, as well as powered elevation from -9° to +20°) that allowed the tank to fire effectively on the move. The 1A1 added metal-rubber skirts along the hull flanks to protect against HEAT warheads, and the gun barrel was wrapped in a [[Thermal sleeve|jacket]] to reduce deviation from thermal loads. The track was changed to a D640A double-pin type with detachable, rectangular rubber pads instead of the earlier double-pin Diehl D139E2 track with vulcanised treads. The rubber pads of the new tracks could be easily replaced with metal X-shaped grousers for movement on [[ice]] and snow. 20 grousers were provided for each tank and stored on brackets on the front hull upper glacis when not in use. A new snorkel was developed that allowed for underwater driving to a depth of 4 m after sealing the tank with special plugs. The driver's and commander's active infrared night vision periscopes were replaced with passive image intensification night sights.<ref name=":0" />

Between 1975 and 1977, all of the tanks in the first four batches were brought to the '''Leopard 1A1A1''' standard, and given additional turret armour developed by [[Blohm & Voss]] which consisted of rubber-lined steel plates bolted to the turret (including the rear turret basket) with shock-resistant spacers. The gun mantlet received a wedge-shaped armoured cover made from welded steel plates and the engine's air intake system was improved. Thus upgraded vehicles weighed 42.4 tonnes.

An upgrade in the 1980s added a hybrid LLLTV/passive IR aiming and observation system, which were being handed down from the Leopard 2 as they were themselves upgraded to thermal imagers. The PZB 200 [[Low light level television|low light level television (LLLTV)]] system with IRS 100 infrared scanner was developed by AEG-Telefunken and mounted in a protective cage on the mantlet, above the main gun, creating the '''Leopard 1A1A2'''. The system combined an LLTV camera which was a type of [[Image intensifier|image intensification]] device producing a TV picture on the commander's and gunner's monitors, coupled with an IR scanner (sensitive to thermal differences in the 3-5 μm wavelengths and based on a [[Lead selenide|PbSe]] detector) which would superimpose the processed IR image over the LLLTV signal to improve target detection and identification.

In the late 1980s, all-digital SEM 80/90 VHF radios were issued to the Bundeswehr and installed in various models of the Leopard 1; the Leopard 1A1A1 with these new radios received the '''Leopard 1A1A3''' designator, and those vehicles with the LLLTV/IR system and SEM 80/90 radios would be known as the '''Leopard 1A1A4'''.