Sorry Dude, I'm behind on this again.
I must be in the hard of thinking class on this. Would you just confirm - or jump all over
- what I am visualising here please?
Due to some quite esoteric disturbance in the area where fuel first hits compressed air, the flame front either detaches from the nozzles or establishes some way downstream? As far, indeed, as the turbines with a very hot (too lean?) mixture that damages the blades? Is that anywhere on the right track?
The closest analogy I can think off is with a plumbers blow torch, where the fuel pressure/temperature is disturbed while lighting it. The flame detaches from the burner and exists - usually briefly - up to an inch from where it ought to be, often with a very harsh, high pitched roar. I've seen it happen with my oxy/acetylene torch on light up as well, but only briefly and it usually goes out.
Roger.