Chappell entered military service during December 1915 as a
private in the South African Cavalry. He then joined
Inns of Court Officers Training Corps in England, and was commissioned a temporary
second lieutenant on 17 June 1916. He also underwent pilot's training, receiving
Royal Aero Club pilot's certificate number 3329 on 17 July 1916; on 24 August 1916
Second Lieutenant R. W. Chappell was appointed a
Flying Officer in the
Royal Flying Corps. In September 1916, he was posted to 27 Squadron RFC as a
Martinsyde Elephant pilot. On 27 March 1917, Chappell scored a second "out of control" win while piloting an Elephant. He was withdrawn from combat during May 1917 and remanded to instructor duty at the
Central Flying School. He was promoted to temporary
captain and rated as a
flight commander on 27 July 1917. In October 1917, he returned to the front as a flight commander and
Royal Aircraft Factory SE.5a fighter pilot in 41 Squadron. On 2 February 1918, Chappell destroyed a German
Albatros D.V over
Erchin and sent another down out of control. On 6 March, he drove down a
Pfalz D.III fighter over
Niergnies, and became an ace. Ten days later, he burned a German
LVG reconnaissance two-seater over
Brebières. A week later, on 23 March 1918, he sent down an Albatros D.V over
Bourlon Wood. The next day, he drove down two
Fokker Dr.I triplanes for his eighth and ninth wins. The following mid-morning, he destroyed an Albatros D.V over
Sailly. There would be one final victory on 16 May 1918; a German reconnaissance machine was sent down out of control southeast of
Arras. Chappell carried his rank of temporary captain over into the new
Royal Air Force on its formation on 1 April 1918, although he was confirmed in this rank at some time thereafter. ==Post World War I==