After extensive trials of three MOWAG Piranha (6 × 6) AFVs fitted with the Norwegian Kvaerner Eureka A/S Armoured Launching Turret (ALT), and three vehicles fitted with a pedestal-mounted TOW launcher which retracted under full armour protection when not required, the former was selected by the Swiss Army. The system has the official Swiss Army designation of the Panzerjager 90 (PzJg 90).

The Swiss 1986 Armament Programme proposed SFr911 million for the procurement of 310 Swiss MOWAG Piranha (6 × 6) anti-tank vehicles fitted with the Armoured Launching Turret (ALT), to be issued to 31 anti-tank companies at that time equipped with the 106 mm 58 (US designation M40A1) recoilless anti-tank gun.

These 310 vehicles were delivered between 1989 and 1992 with MOWAG building the Piranha (6 × 6) chassis and installing the ALT which was manufactured under partial licence by the Ateliers Fédéraux with the total Swiss share being 70 per cent.

The Federal Aircraft Factory at Emmen built about 49 per cent of the aiming system, including day and night sights, and almost 55 per cent of the Raytheon Systems Company TOW 2 guided missile and simulators.

This was the first MOWAG Piranha to enter service with the Swiss Army and more recently the improved MOWAG Piranha 8 × 8 has entered service. Since then the Swiss Army has procured large quantities of the 8 × 8 version of the MOWAG Piranha for a variety of roles, including armoured personnel carrier. More recently a number of specialised versions have been ordered including electronic warfare and NBC.

Following trials with a prototype ambulance vehicle delivered in March 2004, late in 2005 MOWAG was awarded a contract to convert a total of 40 of these TOW anti-tank vehicles into ambulances for the Swiss Army. Additional details are given under variants.

The MOWAG Piranha (6 × 6) vehicle used for this mission is virtually identical of the Piranha (6 × 6) armoured personnel carrier but modified for the anti-tank role. The five-man crew consists of commander, gunner, loader, driver and combat orderly.

The hull is of all-welded steel armour construction, which provides the occupants with protection from small arms fire and shell splinters, with the driver seated at the front left with the engine compartment to his right. The driver has a single-piece hatch cover that opens to the left and three forward-facing day periscopes, the centre one of which can be replaced by a passive night driving device.

The commander is seated to the rear of the driver with a raised cupola for improved observation. This is provided with a single-piece hatch cover, three day observation periscopes and a sighting periscope.

The ALT is mounted in the centre of the hull roof with two Raytheon Systems Company TOW 2 missiles with a maximum range of 3,750 m being mounted one either side. An additional eight TOW missiles are carried in racks in the right side of the rear compartment and are loaded manually via the rear roof hatch. It takes about 45 seconds to reload two new TOW 2 missiles. The ALT has day/thermal sights, which allow targets to be engaged under all weather conditions.

Turret traverse is powered through 360° with launcher elevation from -12 to +15°. The turret is also provided with eight 76 mm smoke grenade launchers which are identical to those fitted to other Swiss armoured fighting vehicles. These are mounted on the upper part of the turret rear and fire forwards.

The rear crew compartment has a bench seat down the left side and in the roof, one either side, is a fixed day periscope to give observation to the side of the vehicle. Normal means of entry and exit is via the power-operated ramp in the hull rear, which is provided with an emergency door.

The MOWAG Piranha anti-tank vehicle is not amphibious as this was not a requirement of the Swiss Army. Standard equipment includes a front-mounted winch with a capacity of 7,000 kg, which is provided with 40 m of cable. A Raytheon Systems Company TOW standard tripod ground mount is carried to enable missiles to be launched away from the vehicle if required by the tactical situation.

• Ambulance

In December 2005 MOWAG was awarded a contract by the Swiss Army to convert 40 of these TOW anti-tank vehicles into armoured ambulances. These will replace part of the Pinzgauer (6 × 6) unarmoured ambulance fleet that will be removed from service by the end of 2008.

As overall systems integrator, MOWAG will be responsible for the conversion of these vehicles as well as logistic support with deliveries taking place from 2006 through to 2007.

The vehicle has space for a maximum of three reclining or six seated patients plus a maximum four-person crew. The interior layout corresponds with respect to space and equipment which includes air conditioning and lighting to meet the requirements of a modern ambulance vehicle.

Equipment carried includes splint material, recovery material, respiratory equipment, oxygen, infusions and bandaging material.