There is only one thing you have to know about spins. To enter one you
need 2 things to be present; stall and a yaw rate. All the rest is
simply stating different ways to make these two things happen.
You can spin a spin capable airplane from any flight condition,
coordinated or uncoordinated, straight and level, a turn, a climbing
turn, a descending turn; it doesn't matter. Just induce a stall either
at 1g or accelerated above 1g, introduce a yaw rate at that stall, and
you will have a spin.
Don't get all bogged down in specifics trying to explain whether an
airplane will spin from this or that. It simply confuses the issue.
The answer to your question is simple aerodynamics. Yes, you can spin an
airplane from coordinated flight and yes, you can spin an airplane from
a climbing turn. All that is needed from ANY flight condition is to
induce a stall and at that stall, induce a yaw rate.
Todd W. Deckard wrote:
> Can you depart and spin from coordinated flight? Specifically a
coordinated
> climbing turn?
>
> Several weeks ago I chimed in on an otherwise awful thread suggesting
that
> if the ball was in the center
> the airplane would not spin. One of the posters
> (Dan_Thomas_nospam@[EMAIL PROTECTED]
) responded that the difference
> in relative wind between the inside/outside wing during a climbing turn
> would result in an assymetrical stall
> and wing drop even in coordinated flight. He had several
> Canadian/Australian citations to back it up.
>
> He posted summaries of them originally and my apologies for
re-constructing
> them:
>
> Full power stalls in a balanced climbing turn tend to result in the
outer
> wing stalling first, because of the higher aoa of the outer wing, with a
> fairly fast wing and nose drop (particularly so if the propeller torque
> effect is such that it reinforces the roll away from the original
direction
> of turn and the aircraft is a high wing configuration) and likely to
result
> in a stall/spin situation that any pilot lacking spin recovery
experience
> may find difficult to deal with. If the climbing turn is being made with
> excessive bottom rudder then the lower wing might stall first with the
> consequent roll into the turn flicking the aircraft over. Recovery from
a
> stall in a climbing turn is much the same as any other stall - ease the
> control column forward to about the neutral position, stop any yaw,
level
> the wings and keep the power on.
>
> http://www.auf.asn.au/groundschool/umodule11.html#climb_turns
>
> When the aircraft stalls in a climbing turn, the high wing is at a
greater
> angle of attack than the low wing and therefore stalls first, which
results
> in a rolling motion toward the high wing, creating asymmetric lift and
drag.
> The down-going wing will stall further as a result of less lift and more
> drag than the up-going wing. A deeper stall, generated by aft C of G,
will
> aggravate these asymmetries, increasing aircraft rolling and yawing
moments
> into the down-going wing. In addition, the aft C of G reduces the
distance
> from the C of G to the centre of pressure of the vertical fin, thus
reducing
> directional control authority, making recovery more difficult
>
>
http://www.tsb.gc.ca/en/re****ts/air/1994/a94o0316/a94o0316.asp?print_view=1
>
> In a climbing turn, the outside or upgoing wing is meeting the relative
wind
> at a slightly higher angle of attack than the lower wing. If we pull
on
> the column to the stalling bite, then the upgoing wing will reach it
> first...The upgoing wing suddenly drops and the wing falls away from the
> original direction of turn.
>
> http://www.casa.gov.au/fsa/2000/sep/FSA34-35.pdf
>
> The Trans****t Canada Guidelines on Stall Training and Spin Awareness
> specifically requires demonstrations in coordinated climbing turns:
>
http://www.tc.gc.ca/civilaviation/general/Flttrain/TP13747/stalltrain.htm
>
>
> I would have thought that the hamfisted chandelles I perform would have
> flirted with disaster if this were the case. However while I have had
to
> demonstrate accellerated stalls from 20 degree banks, I cannot recall
having
> to deliberately stall the airplane from a climbing turn.
>
> My question to uunet is; can you spin from coordinated flight?
Regardless
> the previous dialog did get me thinking:
>
> The convergence of insufficient right rudder and a slipping turn, the
left
> turning tendencies and the
> assymetrical stall could gang up on our hapless pilot resulting in a
quick
> snap and
> spin during a climbing right turn away from obstacles in the departure
path.
>
> Regards
> Todd
>
--
Dudley Henriques
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