He scored a pioneering night fighter victory on 31 May 1918, when he shot down a German Friedrichshafen G bomber.
Banks was commissioned as a second lieutenant in the 5th (Flintshire) Battalion of the Royal Welsh Fusiliers (later the Royal Welch Fusiliers), on 10 December 1914, having been a cadet in the Oxford University Contingent, Senior Division, Officers' Training Corps.
[4] On 28 January 1918, while flying his Sopwith Camel on Home Defence duties with 44 Squadron, he teamed with Captain George Hackwill in driving down and capturing a raiding German Gotha G.V bomber, serial no.
[2] Between 6 April and 31 May 1918, he reeled off five more wins; for the last of these, he drove down and captured a Friedrichshafen G bomber at ten minutes before midnight for the first victory over this type.
His final tally was two enemy planes captured, six destroyed, and four driven down out of control, although one of the latter was shared with Captain Cecil Frederick King.