AF447

[Starbear]

Above optimum altitude

There is much talk of this aeroplane possibly being operated above optimum altitude or in "coffin corner" but so far I have not seen any reference to the obvious remedy.

I refer only to a serviceable aeroplane here but if anyone finds themselves with insufficient thrust to maintain speed through turbulence when above optimum altitude or above severe turbulence recommended levels, there is always the option of descent.

If it is serious and immediate enough such that speed is decaying even with max thrust, forget clearances, forget everything except getting that nose pointing downwards, with appropriate max thrust, to recover speed. Turn off track; use TCAS; anything but get that speed margin back, pronto but by definition the margin to MMO will be very small initially.

If significant unserviceabilities are added to the equation, the problems will magnify hugely but the basic principle remains.

Question: Does anyone advocate or ever been taught to use speedbrake to recover from MMO exceedances? I have found conflicting information in certain manufacturer's training manuals. I see a benefit in using a rapid application of speedbrake against thrust in certain conditions and perhaps avoid speed then reducing too far with consequent lag in thrust application again.