The son of Gerald and Marguerite Fitzgibbon, Desmond Fitzgerald Fitzgibbon joined the Royal Naval Air Service on 28 May 1916. Flight Sub-Lieutenant Fitzgibbon received Royal Aero Club Aviator's Certificate 3529 on a Maurice Farman biplane at Royal Naval Air Station, Cranwell on 14 August 1916. On 5 May 1917, he was posted to 10 Naval Squadron where he scored 8 victories flying the Sopwith Triplane and Sopwith Camel before being reassigned to the Home Establishment on 15 October 1917.
Great Britain, Royal Aero Club Aviators' Certificates, 1910-1950
Distinguished Service Cross (DSC)
Act. Flt.-Lieut. (now Flt.-Lieut.) Desmond Fitzgerald Fitzgibbon, R.N.A.S.
For exceptional courage and determination in leading offensive patrols against enemy formations, although often outnumbered by them. On the 14th September, 1917, he and his patrol of seven machines attacked a hostile formation of eight enemy scouts. In the combat that ensued three hostile machines were brought down completely out of control, one of these by Flt.-Lieut. Fitzgibbon, while the patrol suffered no casualties.
On the 26th September, 1917, he attacked with his patrol of eight machines fifteen hostile scouts. He himself engaged four different machines, one after the other, finally driving one down completely out of control.