True story of WW2. During initial flight testing of the Bell XP-59 at George AFB (then Hawes Field) CA, Bell personnel could be distinguished by their trademark black derby hats. Although the airspace around George and Muroc Dry Lake was restricted, P-38 Lightning pilots from a nearby Army field would occasionally invade the area to see what was going on at the "secret" base. Two Lightnings spotted one test-run with the Bell jet smoking from its engines and assumed it was a prop fighter on fire. Upon closer inspection they marveled that it was a propellerless plane and rumors started to leak of a US jet fighter (they had not been informed of the German jet and rocket craft yet). To stop these leaks the XP-59s were fitted with fake wooden propellers on the ground and shrouded, but in the air there was the Lightning risk. So a prank was devised by a test pilot named Jack Woolams. On one low-speed flight, Bell test-pilot Jack Woolams spotted one of the snoopers approaching, and was ready for him. He pulled on a rubber gorilla mask he had brought along, put on his derby, and stuck a big cigar in his mouth, then let the P-38 pull alongside his jet. He glared back at the stunned pilot, who quickly broke off and headed for home. There was no official follow-up to this episode, but it was the source of much hilarity among Bell workers who speculated about the story being told that night at some Officers Club of a propellerless plane being flown by a cigar-smoking gorilla wearing a derby hat! That stopped the leaks for a while until the USAAF bombers over Europe started to encounter the radical jet Me-262 in 1944 as well as the rocket fighter Me-163. The Germans then added the Ar-234 jet bomber/recon a/c and lastly the He-162 jet fighter of 1945.

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