The base at Ballykelly was opened in 1941 to provide long-range reconnaissance, crews from here patrolled the north Atlantic locating German U-Boats and provided air support for convoys crossing the Atlantic. The first active operations were by 220 Squadron which flew Boeing B17 Flying Fortresses. They were later joined by 120 Squadron flying Consolidated Liberators. The range covered by these anti-submarine and convoy support units extended from Norway to the Bay of Biscay and flights could last up to 15 hours. The main runway was extended in 1943 and crossed the railway line from Derry to Belfast. An unusual rule applied which gave trains the right of way if a plane was on approach.

Lining the wall at the far end of the church grounds, a row of military headstones tell their own stories of young men who lost their lives and were associated with the airbase which was operational during WW2.  Young men like G.W. Gerring and W.G. Wallace who were returning from a long maritime patrol over the north-western approaches, on arriving at Ballykelly they found the base and area hidden in thick mist. The Liberator running low on fuel was heard circling overhead, on the third pass it crashed in bad visibility on Binevenagh mountain with the loss of all the crew (Captained by Pilot Officer I B Jenkins, 2nd Pilot: Warrant Officer G.F. Logan; Navigator: W/O R.R.J. Revell; Sgts W.H. Wilson, H.G. Lewis; W/Os G.W. Geering, W.G. Wallace; Flt Sgt H.G. Coombes).