Aubrey was born in 1922 in Southampton to Victor and Barbara Cohen. In 1939 the family lived at Henstead Court, Southampton where Victor worked as an optician and the family changed their surname to Cowan.

Anson N9565 of 3 AOS took off from RAF Edgehill on 22 May 1942 and hit high tension wires near Edgehill.  All four crew members were killed.

The crew were:
Pilot, P/O Godfrey W Ardley, 120726
W/Op, P/O Charles A Harris, RCAF J/7089
Sgt Aubrey H Cohen
Obs, Sgt Stanley Laws, 1186751