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aileron, either, because yaw is a
secondary effect of roll. In addition,
aileron drag will only make the
situation worse.
Keep pulling the elevator back, in
attempt to maintain height. About 5-
10 kts before the proper stall, you
might hear the stall warning going (if
you've got one), or feel a little
buffeting in the controls. This is the
aircraft protesting that it can't stay
up in the air, and that it is reaching
the critical angle of attack –
turbulent air is hitting the elevator
and other controls.
At the stall, the nose will pitch
down, usually just after the elevator
reaches its full limit of travel
backwards. The dropping could be
relatively mild, or quite severe,
depending on the design of the
aircraft (sometimes, you don't even
notice it!).
The point to realise is that, in
dropping the nose, the angle of
attack improves enough to get lift
again, and the aircraft starts flying,
even if you keep the control column
back, but we want to recover, so
relax the back pressure, and note
how much height is lost during the
exercise, once you recover the cruise
attitude. It will be around 350 feet,
quite critical near the ground, so
applying power just after relaxing the
back pressure will reduce this to a
minimum, sometimes down to
below 100 feet.
Spinning
When spinning, the aircraft is out of
control in all three axes of flight. It
results from uneven stalling. A spin
is basically a stall that is not straight.
That is, you are turning and
descending with one wing (the
downgoing one) in a permanent stall,
hence the spin. The effect is a
continuous roll, which causes yaw.
Left to itself, the aircraft will not
recover, as long as the one wing
remains stalled.
You can't use aileron to get out of a
spin, because of aileron drag making
the condition worse, but rudder is
available, so you shove in a bootful
in the opposite direction to the turn,
until the yaw stops. Then relax the
back pressure on the elevator to
pitch the nose down and reduce the
angle of attack on the stalled wing
(this may be done at the same time,
depending on the machine). Do not
use ailerons, and pull out of the dive
once you have some airspeed. Then
apply power as necessary.
The aircraft must stall first, so if you
avoid stalling you won't get into a
spin. To start a spin deliberately,
shove in a bootful of rudder at the
point of the stall.
Before performing any manoeuvres,
however, you should do:
The HASELL Checks
Remember these well, as they are
useful throughout your flying,
particularly with steep turns:
· Height – are you high enough to
perform the exercise and to
recover if something should
happen, without hitting the
ground?
· Airframe – clean – flaps are in,
undercarriage is up, etc.
· Security – hatches and harness all
secure (i.e. doors closed and
seat belts done up), no loose
20 JAR Private Pilot Studies
articles in the cabin that could
fly about and injure you, etc.
· Engine – fuel is on, and enough
for what you want to do, with
temperatures and pressures OK,
carb heat green, etc. (carb heat
should be on before reducing
power below a certain RPM, as
it won't have enough power to
defrost if any already exists).
· Location – no good wondering
where you are when the engine
stops, better find out now! Also,
make sure you are not over
anywhere you are not supposed
to be, like congested areas,
water, etc.
· Lookout – make sure there is no
traffic above, below or around.
Do a couple of turns to make
sure, but not a steep turn at this
stage, because you will learn
how to do them later!
Low and Slow
This manoeuvre, which is defined as
operating somewhere between stall
and endurance speeds, can kill the
unwary. It's commonly used on
pipeline inspections, or police
patrols, and is especially dangerous
with steep turns. When banking hard
over, your lifting aileron is fully
deflected, so you can turn.
Unfortunately, it's also producing
maximum drag, which will tend to
cause an adverse yaw in the opposite
direction, that is, the aircraft wants
to go right, but is being forced left,
or whatever. In contrast, the aileron
on the other wing has very little
profile above it, so is producing very
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