Re: spins from coordinated flight

Todd W. Deckard wrote:
> "Dudley Henriques" <dhenriques@[EMAIL PROTECTED]
> wrote in message 
> news:euSdnWqz3Z9vKO7anZ2dnUVZ_oOnnZ2d@[EMAIL PROTECTED]
>> 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
> 
> 
You are correct; IF coordinated flight is being defined as ball 
centered. This is indeed what is taught to most new students as they 
begin flight training.....that is until they start doing slips :-))

When and if you get into aerobatics or begin flying with advanced 
instructors with deep aerobatic backgrounds you learn quickly that 
coordinated flight can mean cross controlled flight as well as the usual 
definition with everything going ball centered in the same direction :-)
I once flew a Pitts Special the full length of a major airfield holding 
it in knife edge flight. In the TRUE sense of coordinated, holding the 
aircraft in knife edge would be considered as coordinated flight.

Depending on the instructor, you either learn that coordinated flight is 
with the ball always in the center, or you can be taught that you are 
coordinated when the control pressures are applied in the exact amount 
necessary to place the airplane in the sky at the exact configuration 
required at any instant in time.
I prefer the latter definition and have taught my students this way for 
many years.


-- 
Dudley Henriques