Benjamin was born in 1922 in Spitalfields, London to Russian born Joseph and Rachel Cohen. Benjamin was the youngest of nine children, eight boys and one girl and their father worked as a tailors presser. In 1939 the family were living in Hackney where the male members of the family were working as ladies pressers in the tailoring industry. Benjamin joined the RAF at the end of 1940 when he was eighteen.

Benjamin was on board Wellington HF168 which departed from RAF Limavady, Northern Ireland on 19 Feb 1944 on a Leigh Light patrol. The aircraft disappeared and the court of enquiry concluded the the cause of the accident “must remain a mystery.” 

The crew who died were:
F/Sgt L.J. Stephens, RAAF 9037
P/O, Lloyd Remington Meech, J/85860 , RCAF
P/O A.F. Moore, J93802, RCAF
F/Sgt J.W. Torscher, R/159188, RCAF
Sgt B. Cohen, 1398772, RAF
Sgt J. Richardson, 1566574, RAF

The family of Benjamin were contacted in 1994 by Lieutenant Commander David Harries who was the navigating officer on board H.M.S. Warwick which was torpedoed on 20 February 1944. He gives an account on how many survived because an Air/Sea Rescue operation was looking for the crew of Wellington HF168 in the same area.