The son of Arthur Thomas and Isabel Charlotte Eliza (née Willan) Keen, Arthur Willan Keen was schooled at Aldro, Dunchurch Hall and Rugby before commencing an engineering degree at Trinity College, Cambridge in 1913. His degree unfinished, Keen joined the Army Service Corp (Mechanical Transport) in 1915, as a 2nd Lieutenant.
In November 1915 he joined the Royal Flying Corps and attended the School of Instruction, Reading, Berkshire. Basic flying training followed at Catterick, Yorkshire where Keen achieved his Royal Aero Club Aviator's Certificate 2298 on 17 January 1916, flying a Maurice Farman biplane.
In late January 1916 Keen moved to Montrose, Forfarshire in Scotland, for advanced flying training. By mid-February he had been awarded his RFC Pilot Brevet and was selected to remain at Montrose as a flying instructor. On 17 June 1916, whilst airborne, Keen witnessed another aircraft crash into the sea close to Montrose airfield. He quickly landed, leapt into his car, drove rapidly for the beach, and swam out about 150 yards to rescue injured Canadian pilot 2nd Lt Robert E. A. Macbeth from the submerging wreck. This incident earned Keen the Bronze Medal of the Royal Humane Society (see citation below).
August 1916 saw Keen join his first operational unit, 70 Squadron. Operating the Sopwith 1½ Strutter, the squadron had already begun deploying in July, by individual Flights, to Fienvillers, France, in support of the Somme offensives. On 28 August Keen scored both his, and 70 Squadron's, first aerial combat victory. At the end of October 1916 Keen was briefly posted to No.45 Squadron, as a temporary Captain and Flight Commander, to assist the newly-arrived squadron in gearing up for war. No. 45 Squadron, also operating the Sopwith 1½ Strutter, was co-located with 70 Squadron at Fienvillers.
In early December 1916 Keen returned to Home Establishment, this time serving as a flying instructor with training units at Ternhill, Shropshire and Harlaxton, Lincolnshire.
Keen returned to France at the end of April 1917, to 40 Squadron, newly-equipped with Nieuport scouts and in the throes of moving from Auchel to Bruay, France. He initially commanded ‘C’ Flight which included (then) 2nd Lt Edward C. 'Mick' Mannock amongst its members. During this tour Keen claimed a further 11 victories flying the Nieuport 23, and was awarded the Military Cross (see citation below).
Another Home Establishment tour followed in November 1917, with a posting to HQ Eastern Training Brigade. Keen was then promoted to Major in April 1918 to command a flying training squadron at the Central Flying School, Upavon, Wiltshire.
It wasn't long before Keen returned to 40 Squadron again, in June 1918, this time as Squadron Commander, following the combat death of previous incumbent Major Roderic S. Dallas. No.40 Squadron now operated the RAF SE5a; with this aircraft Keen added 2 further victories to his tally. An unfortunate flying accident at Bruay on 15 August 1918 resulted in concussion and burns, and Keen sadly succumbed to those injuries in hospital on 2 September, 70 days before the Armistice.
Incorrectly listed as Arthur William Keen in some secondary sources. Some sources also incorrectly date Keen's death as 12 September 1918.
Great Britain, Royal Aero Club Aviators' Certificates, 1910-1950
Royal Humane Society Bronze Medal
Awarded to people who have put their own lives at great risk to save or attempt to save someone else.
"Bronze medal to Second Lieutenant A. W. Keen, Royal Flying Corps, for his rescue of Lieutenant MacBeth from the sea near Montrose on June 17th. The aeroplane on which Lieutenant MacBeth was flying came down in the sea, and Lieutenant Keen, who was also flying, seeing the accident, at once landed, and making his way to the place was just in time to save Lieutenant MacBeth, who was trying to swim ashore from the wrecked machine."
T./Capt. Arthur Willan Keen, Gen. List and R.F.C.
For conspicuous gallantry and devotion to duty. He has shown the greatest gallantry and skill in aerial fighting, and his daring in leading offensive patrols into favourable positions for attack has been the means of many hostile aircraft being destroyed and driven down.