It's possible that Ray Holmes' sacrifice was not necessary.
Alfred Keith Ogilvie
Battle of Britain Pilot with 609 Squadron
On September 15th, now celebrated as Battle of Britain day, he shared in the downing of the famous Dornier Do17 which crashed on Victoria Railway Station. At about 1215 hours the Squadron was ordered South-East where over Kenley it waded into a formation of Do17s from KG76. During the melee that followed he launched his attack on Dornier F1+FH, wr.no.2361. Oberleutnant Robert Zehbe, the pilot of the Dornier, and two of his crew were killed but two other crew members succeeded in baling out and were captured. Oglivie's proof was photographic for his 16mm cine-camera, mounted in the wings like the eight.303 guns and synchronized with them, recorded a film showing an almost wingless Dornier fuselage in one part of the sky and its tail unit in another. Though he too modestly admitted that he was not the only attacker - and in fact Sergeant Holmes of 504 Squadron ,who ended up by rolling off a Chelsea roof into a dustbin after baling out, claimed the final victory.
Ogilvie later filed the following Combat Report
"We were ordered to attack a large formation of Dornier 17, 215's with a heavy Me109 escort. In getting in position I saw a lone Dornier seperated from his formation. I went for it and gave it several bursts from the beam. The fire was returned. Two other Spitfires also attacked, and on my next attack I could see fire in the Dornier's cockpit. As I went beneath it I saw two men jump and their parachutes open.
The whole disintegration being a most amazing and terrifying sight. The enemy aircraft spun and broke in half, and dropped somewhere around Battersea.
On orders from base I returned alone and pancaked."
Ogilvie baled out over France on July 4th, 1941 after being attacked by a Me 109. He was captured & spent 9 months in hospital before being sent to Stalag Luft III. He later took part in the famous "Great Escape" & was actually the last to get free before the tunnel was discovered.
Ogilvie was captured after two days and sent to a Gestapo prison at Gorlitz in Czechoslovakia. There during repeated interrogations "I stuck to my story that I was a career officer. This must have registered with the Teutonic mind, because I was one of eight returned to camp - the others, as you know, were shot"
In April 1945 he was liberated and transferred to the Royal Canadian Air Force as a Flying Control Officer. Resuming flying he joined 412 Transport Squadron before later taking command of 129 Acceptance and Ferry Flight upon his promotion to Squadron Leader. He was later appointed to air operations as a Staff Officer and finally operations officer at Downsview Base.
He retired from the RCAF on September 14th 1962 and returned to Ottawa where he lived until passing away in 1998.
PS. I haven't seen it for a long time but I read somewhere that actual footage of the Do 17 crashing was used in the film "Reach for the Sky". I don't know if this was from the newsreel film or Ogilvie's gun-camera - or both.