1994 British Army Lynx shootdown On 20 March 1994 , a British Army Lynx helicopter was shot down by the Provisional Irish Republican Army ( IRA ) in Northern Ireland . A unit of the IRA ' s South Armagh Brigade fired an improvised mortar at the British Army base in Crossmaglen , County Armagh . The mortar round hit and shot down the helicopter , serial number ZD275 , while it was hovering over the helipad . Three British soldiers and a Royal Ulster Constabulary ( RUC ) member were wounded . Background . Since the 1970s , the IRA developed a series of home - made mortars . The goal was to produce devices to be use as " stand - off " weapons , capable of being launched from safe ranges upon police or military outposts , and easy to conceal on dead - ground . The different designs evolved in 1992 into the Mark 15 mortar , widely known as " Barrack buster " . The mortar shell consisted of a one metre long metal propane cylinder with a diameter of 36 cm that contained around 70 kg of home - made explosives and with a range between 75 and 275 m . The cylinder was an adaptation of a commercial ' Kosangas ' gas cylinder for heating and cooking gas used in rural areas in Ireland . The first use of the " Barrack Buster " took place on 7 December 1992 against a security base in Ballygawley , County Tyrone . The attack . On the evening of 20 March 1994 a Lynx helicopter , serial number ZD275 , was in the process of landing at the large British army base at Crossmaglen . Meanwhile , an IRA unit had mounted a Mark 15 mortar on a tractor , concealed behind bales of hay . The tractor was parked 150 yards from the intended target , on waste ground . At 20 : 27 , there was a sudden blackout across Crossmaglen ' s square and at the same time , a single mortar shell was lobbed into the barracks . The IRA had used the mains for the collapsing circuit of the firing pack , turning off the street ' s power supply and allowing the mortar ' s own battery to trigger the launcher . When the Lynx was hovering 100 feet over the helipad , the mortar round hit the aircraft on the tail ' s boom , which was severed from the fuselage . The machine span out of control , but the pilot was able to crash - land the Lynx inside the base . A Grenadier Guards ' patrol spotted a huge orange ball from a mile away . Three members of the crew managed to get out with minor injuries , but a member of the RUC was trapped inside the blazing wreckage . The constable was rescued just before the fuel tanks and the ammunition started to explode . Author Toby Harnden described the incident as the most successful IRA operation against a helicopter in the course of the Troubles . Aftermath . After the incident , the IRA and Sinn Féin bore criticism from the SDLP Member of the Parliament for the area Seamus Mallon , who said : God knows how many people could have been killed . When you realise this mortar was lobbed over a number of houses it brings home the enormity of the danger so many people faced . Yet again you have Sinn Féin talking peace in the morning and carrying out these murderous attacks through the IRA in the evening . John Fee , a local SDLP councillor which dubbed the attack as " an act of lunacy " was later beaten by two men outside his home . The IRA denied responsibility . Corporal Wayne Cuckson of the Royal Logistic Corps was awarded the Queen ' s Gallantry Medal for dragging the wounded constable out of the crashed aircraft . Corporal Robert Tomlinson of the Royal Military Police was also awarded the Queen ' s Commendation for Valuable Service for his part in coming to the aid of the wounded RUC Constable and Soldiers . There was a second mortar attack on a British military helicopter on 12 July 1994 at Newtownhamilton , when a RAF Puma , serial number XW225 and carrying 12 soldiers crash - landed on a soccer pitch after being hit on its tail by another Mark 15 mortar launched from a tractor . No serious injures were reported . The Puma sustained Category 3 or Category 4 damage on the RAF scale . Back to service , the machine was definitively written off and scrapped after suffering another crash - landing in Germany on 15 February 1997 . The downing of two helicopters by mortar fire , along with the increasing sniper activity of the IRA , was both a morale and military blow to the British forces in south County Armagh .