McCudden sometimes flew his personally adapted SE5a to over 20,000 feet to attack high-flying German recce two-seaters. Remarkable man, McCudden, he went from Boy Soldier to Major, VC and all the other gongs in those five years; the RAF lost a potential leader when he stalled in and died in 1918.
An interesting fact: McCudden had a hard time being accepted by 56 Squadron RFC. Although an ace, he'd scored all his victories until then as that great rarity, a Sergeant Pilot raised from the ranks - and the public school snob 'officers and gentlemen' didn't like that one bit.
Another: McCudden was almost certainly Manfred Richthofen's fifteenth 'kill'. On 27 December 1916 the Red Baron reported downing a 'Vickers two-seater' in the afternoon near Arras. No FE2 was lost that afternoon. The only possible aircraft he could have engaged was the DH2 of No.29 Squadron RFC flown by McCudden, who had disengaged, 'turned on my back and dived vertically in a slow spin and in this way regained our lines' after his Lewis had jammed in a fight with 'a HA'. Richthofen's 'kill' came down over the British side of the lines and was 'verified' by two AA batteries. Although McCudden reported the last thing he'd seen as he crossed the lines to safety was some FE2s being engaged by hostile machines, all those Fees returned safely. Richthofen had expected to be awarded the Pour le Merite after his eighth kill but the requirement had been upped to sixteen; maybe his 'throat-ache' desire for Germany's highest gallantry award affected his judgement that day? And he should be credited with only 79 kills and not the 80 that made him the highest-scoring pilot of WWI? This info is to be found in 'Under The Guns Of The Red Baron' by N.Franks, H.Gilbin and N.McCrery; 1995, Grub Street, London, ISBN 1-898697 27 2, pages 46-50.