I never saw it myself from outside, but when starting the boost, at night, just before entering the runway, I had a couple of comments that flame had appeared on light up.
From a Clipper 747: "...er tower...there's a sheet of flame just come out of the APU on this seven twenty seven ahead of us here holding 28R.....".
Tower: " Speedbird XXX confirm you've just started your boost?"
I suppose using the boost was a relatively unusual occurence anyway, I suspect about 5% of take offs max??
I also recall a couple of occasions ex Malta and Naples in T3's (and NIC in a T2) climbing into a severe inversion and it was only the curvature of the earth that gave us a climb. IIRC the Malta incident that Prober refers to prompted a serious look into the phenomenon, and there was a subsequent temp correction applied worldwide to all types for T/O performance in such circumstances.
Fortunately the T3 couldn't make NIC or TLV in one go.
Last edited by Hobo; 28th Dec 2010 at 07:21.
Reason: minor + spelling!!