Engine Fire of Surge?
Hello,
this is my first, and probably only, post on this great site. I am a retired computer jock who made a living as a consultant flying around the world for 25 years. During that time I flew on commercial flights about 15 times a month - I retired 10 years ago and am still trying to use my frequent flyer miles. The only thing I know about big airplanes is what I've picked up talking with pilots in adjacent seats on those long transcontinental flights and from reading material here.
I was at a high school baseball game exactly two statue miles south of the south end of the SeaTac airport when this incident occurred. The school is on a hill top and has an unobstructed view south toward Tacoma. Planes were taking off to the south at the time of the incident.
I heard two large explosions, about 2 seconds apart. I thought it was thunder at first since we had some last night. But the reports were very sharp with a cracking aspect.
I then turned and looked northward and saw the 777 come over the top of the school at about 1500'. It did not appear to be climbing or accelerating. The plane flew directly overhead and continued on southward. It was flying much slower than any jet I've seen taking off from SeaTac.
The port engine was emitting a long plume of yellowish flames that tapered to a fine point but with no smoke. The flame was clearly coming only from the exhaust of the engine and was about as long as the engine nacelle.
The interesting aspect of the flame that it was cycling on/off in about 2 or 3 second pulses. It would burst forth for several seconds and then be gone for a second or two. The cycle was very regular and continued for as long as I could see the plane which was well over a minute after it went overhead.
As the plane disappeared I could still see the flame cycling on/off against the dark clouds beyond the plane. I never saw the signs of burning hydrocarbon - no smoke/no smudge (in a previous life I was trained as a fire fighter in an oil refinery) and no sign of anything burning in the normal sense.
The flames did not look like a fire - they looked like an afterburner that I've seen in videos and sometimes see at McChord.
I have read several posts about engines surging (if that is the correct term?) on takeoff and the pulsing jet of exhaust was certainly surging in a regular pattern.
Does my description sound like something other than a fire?