spins from coordinated flight

clarification edit inserted
"Jim Macklin" wrote in message
...
| In my experience, a stall break while straight and level or in a 60 degree
| bank if perfectly coordinated will drop the nose straight down.
[edit--relative to the pilot, not the horizon]
| The kicker is that 98% of the pilots have lazy feet and don't really keep
| the aircraft coordinated. If power is ON, the aircraft will need more
| rudder to control yaw and that amount of rudder will increase as speed is
| decreased approaching the stall. Some airplanes may not have enough
rudder
| to stay coordinated to the stall, most pilots will not use the rudder that
| is available.
| Some airplanes will not spin, even wit yaw supplied by maximum rudder
input
| at the stall in a pro-spin direction. The Beech Skipper [BE77] requires
| that the stall be entered, just before the stall, full pro-spin rudder is
| applied to induce a roll. At a 90 degree bank angle, sudden and full
| aileron in the opposite direction as the rudder is necessary to stall the
| wing crisply at the outer half. That will cause the airplane to roll
| rapidly and enter a spin. If not timed or done correctly, the aircraft
will
| enter a spiral.
|
| In the accidental spin, the pilot is likely to do exactly the same thing,
| just not with thought and skill. The plane is stalled while yawing
| [uncoordinated] and when the break happens, the poorly trained and
| non-current pilot's reaction will often be to try to pick-up the wing that
| is falling and the nose with aileron and up elevator. The natural
reaction,
| which training and experience correct, is to "fight" the falling nose, the
| falling wing, with normal control input.
|
| IF the aircraft is coordinated perfectly, the difference in lift vector is
| due slightly to the radial airspeed difference between the L&R wings, but
| more my the dihedral built in the airplane. The problem is that flight is
| very dynamic, control forces are changing, humans have reaction times, and
| the control authority created by the aerodynamic surfaces rapidly falls
with
| a small decrease in airspeed [lift equation] and the other forces, such as
| P-factor and engine torque involve inertia and mass.
|
|
|
| "Todd W. Deckard" wrote in message
| ...
||
|| "Dudley Henriques" wrote in message
|| ...
|| 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.
||
|| So to corner your answer to my question: you cannot? spin from
| coordinated
|| flight.
|| The airplane must be yawed during the stall break (thus the inclinometer
|| ball slips or skids
|| to one side).
||
|| My question is not to seek out practical advice in spins, or recoveries.
| It
|| is to explore two
|| academic debates: Can a certificated airplane depart if the ball is
|| precisely in the middle
|| and is there something telling in the emphasis from the foreign sources
|| cited that exposes a
|| gap in our US training practices and material.
||
|| Thank you for your response.
||
|| I'll be making a new years resolution to try it out in the neighboorhood
|| Decathalon (with an appropriate
|| chaperone) but as it is cold and snowy I thought I would put it to the
|| uunet.
||
|| Best regards,
|| Todd
||
||
|
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