JP233
The JP233 was a British submunition delivery system consisting of a pair of large pods carrying several hundred submunitions designed to attack runways.
A Panavia Tornado equipped with the JP233 would fly over a target runway, at which point the pods would dispense their payload. This is an unusual feature of the JP233, as most other submunition delivery systems essentially function as free-falling bombs rather than remain with their aircraft during operation. However, the pods are jettisoned once empty.
Each JP-233 was divided into a rear section with 30 SG-357 runway cratering submunitions and the front section carrying 215 HB-876 anti-personnel mines. Both types of submunitions were retarded by small parachutes.
The SG-357 weighed 26 kilograms (75 pounds) and was a two-stage munition — a shaped charge in the front blasted a hole in a runway's concrete. A second charge fell into the hole and exploded, producing a large crater. The HB-876 anti-personnel mines would lie scattered on the surface, making rapid repair of the runway nearly impossible. They would explode at preset intervals or if disturbed and were capable of disabling bulldozers or other earth-moving machines.
The whole operation was rather frightening to the flight crew, to say the least, since it required the aircraft to fly low, straight and level over an enemy airfield. There is a myth that a number of British Tornadoes were lost to Iraqi groundfire while carrying out JP233 attacks during Operation Desert Storm. Only one of the JP 233 missions were shot down, and that was three minutes after the attack had been completed. The other Tornado losses were incurred when lofting 'dumb' bombs on Iraqi air defence installations.
What did alarm the crews of British and Saudi Arabian Tornadoes using JP233 during the First Gulf War was that the aircraft was brightly illuminated at night by the exploding munitions, and also the violent trim changes as the containers were jettisoned usually caused the auto-pilot to cut out, so that the aircraft would suddenly rocket up several hundred feet.
But with the increasing availability of standoff attack munitions capable of the same mission with little risk to the flight crew and aircraft, as well as the British entry into the Land Mines Treaty (which declares the HB-876 illegal), the JP233 has been withdrawn from service.
The JP-233 was built by Hunting Engineering (now known as INSYS). It was originally conceived in the late 1970s as a cooperative programme with the US Air Force, which wanted to use the weapon with its FB-111 strike aircraft. Rising costs forced the USAF to pull out of the programme, but the British completed development on their own.