Holligan was commissioned as temporary second lieutenant (on probation) in the Royal Flying Corps on 29 August 1917, and was confirmed in his rank, with seniority from 14 December 1917, on 14 March 1918. Holligan was posted to
No. 49 Squadron in France, as an observer/gunner in a
DH.9 bomber. He gained his first victory on 8 March 1918, flying with pilot Second Lieutenant
Gordon Fox Rule, by driving down a
Rumpler C reconnaissance aircraft over
Brebières. Two days later, on 10 March, Holligan and Fox Rule drove down another reconnaissance aircraft, a
LVG C, over
Marquion. His third victory came on 23 April, with pilot Lieutenant A. H. Curtiss, shooting down an
Albatros D.V east of
Nieuport. Holligan's final three victories came on 8 and 9 August, all
Fokker D.VIIs, with pilot Captain
Clifford Bowman, over
Béthencourt,
Falvy and
Marchélepot. Holligan finally left the RAF, being transferred to the unemployed list on 1 February 1919. ==See also==