To
all Sim Pilots I'd like to say hi !
Subject:
Stalls
I'd
like to cover a subject that I've talked about to many pilots
and simmers and was surprised to find out that they were all unaware
of the different types of stalls, so I'll list them now and talk
alittle about each one.
A.) Power-on Stalls; This type is basically associated
with takeoffs and climb, gear and flaps up!
B.) Power-off Stalls; usually encountered on
approaches; Flaps and gear down.
C.) Elevator " Trim Stalls"; on final
approach, the aircraft is usually trimed for the landing speed
with nose up trim, as power is applied for a go-around, the normal
tendency is for the aircraft to pitch up, and if positive pressure
is not used to counteract the strong trim forces, the nose will
continue to pitch up.
D.) Secondary Stall; If you pull up too quickly
during recovery from a stall, you may trigger a secondary stall.
Relax and let the aircraft regain flying speed by slowly pulling
back on the stick.
E.) Accelarated Stalls; or what I refer to as
" High Speed Stalls", This I find is the one that almost
all pilots find hard to believe, how can an airplane stall by
going to fast? These stalls are usually caused by abrupt or excessive
control movement, and commonly occur during steep turns or rapid
dive recoveries involving high load factors or a sudden change
in the flight path. This type of stall is usually more violent
and often unexpected because of the relatively high airspeed.
In 1979 a TWA 727 fell 36000 feet before finally recovering from
what I believe was a high speed stall. The aircraft was flying
at FL 340 and had a 110 knot headwind , the captain wanted to
make good time so it was cleared through ATC to climb to FL390;
up to this time the flight was perfect, but after a few minutes
at the higher altitude the Captain felt a vibration under his
feet, and then the whole cabin started to shake, the aircrafts
left wing dropped and the nose went straight down, the captain
tried everything to regain control, nothing happened, then he
finally told the co-pilot to lower the landing gear and the aircraft
responded, leveled out, they called for an emergency landing,
and all 89 passenger and crew were saved. The trick here is to
learn to recognize buffeting at high speed as you're warning signal
that your too heavy and the air too thin to continue at the present
angle of attack.
Till next time, great flying to you,
Capt Steve
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