t was September, 1967, early swing shift at SFO where TWA's CV880 N830TW (fleet nr. 8830) was arriving with number one engine shut down for a fire warning. This was in the early days when TWA had turn-in, turn-out gates with the airplanes parking parallel to the terminal and a jetway front and back.

Today 8830 was to turn to flight 176 to Las Vegas. The fire warning had gone out when the throttle was retarded so the bottles weren't fired, we set out to find the source of the warning. A start truck hooked up to the bleed air system soon revealed a fractured duct inside the number one pylon. Bleed air is very hot, it can weaken pylon structures and melt solder in electrical connectors.

This duct was about eighteen inches long, about four inches in diameter, had an expansion bellows and several strange turns. We didn't have one in stock but American provided a pool part from a CV990A. I grabbed the new part eager to put it in and avoid a delay when I noticed it didn't look a thing like the other part. I pointed this out to the line foreman, Ed Thorpe. Ed scratched his head and then said "Put it in anyway". "Huh?" I asked. "You heard me, put it in anyway"."OK", I said, but it's not going to fit".

A TWA Convair 880 is next for takeoff on Rwy 1R at SFO. The TWA hangar (the new international terminal stands at it's place) and the tail of a 747 can be seen in the background.

Seconds later I felt like a total fool, the fit was perfect. Then I remembered seeing the old example of an optical illusion, a block with three prongs sticking out of it except that one way you looked at it the prongs were incomplete. I had been fooled by the odd shape. Flight 176 left on time and I had crow for lunch.