CFI oral intel

Michael Ash wrote:
> Hilton wrote:
>> Michael Ash wrote:
>>> In a steady *spiral* dive the wing loading will be determined by your
>>> bank
>>> angle.
>>
>> Can you prove that? (mathematically or non-mathematically)
>
> If it's steady, i.e. constant speed, then the loading will be equal to the
> arccosine of the bank angle, because you need to generate 1 gee straight
> up to counterbalance gravity. This is the same situation as a level turn,
> and the math and vectors should be discussed in any introductory book on
> flying.

Your 'proof' above is almost correct for *level* flight (it ignores attitude
etc, but I don't want to knit pick), however, it is not appropriate at all
in a spiral even if the aircraft is at a constant speed. In a spiral, there
is a non-zero component of vertical drag, therefore less vertical lift is
required. However, your lift vector is now at an angle to the vertical.
You cannot ignore these. Therefore the wing loading is also a function of
the coefficient of drag, and perhaps other things, but clearly not only
determined by your bank angle.

Hilton

Michael Ash <mike@mikeash.com> wrote in news:1212717258.920305
@web1.segnet.com:

> In rec.aviation.student K l e i n <kleing@********> wrote:
>> If this worked reliably, it would be taught as a standard technique
>> for inadvertant VFR into IFR excursions. Hey, just throttle to idle,
>> hands off and wait for VFR to appear. But....this is not what is
>> taught. Wonder why???
>
> One reason that comes to mind is that you have no guarantee that the
> ceiling under your IMC condition is high enough to allow for recovery.
>

Well, "inadvertant flight into IMC" is almost always a push on regardless
scenario where the pilot gets lower and lower, often in inhospitable
terrain, so it'd be kind of useless in that anyway.


Bertie

On Jun 5, 4:01 pm, K l e i n <kle...@********> wrote:
> If this worked reliably, it would be taught as a standard technique
> for inadvertant VFR into IFR excursions.  Hey, just throttle to idle,
> hands off and wait for VFR to appear.  But....this is not what is
> taught.  Wonder why???

Well, two reasons. One, because there is no guarantee that you will
reach stability in a bank without exceeding Vne (and in fact in many
airplanes you will not - wings or tail will come off). Two, because
recovery from a spiral dive actually takes a fair amount of altitude,
and trying to do it quickly will likely break something as you will be
well above Va.

> This is curiously close to a technique for spin recovery that is
> taught for certain aerobatic airplanes such as the Pitts and the
> Extra, called Muller-Beggs.

Well, OK - but it's not a technique at all. It is simply a
demostration that the airplane will not remain wings level at trim
speed without pilot input for very long, expecially in the event of
engine failure. Quite the contrary, an active recovery will most
likely be necessary.

If the demostration is wrong, then the plane WILL remain wings level
(the way a ram-air parachute will). Now THAT would be useful for
inadvertent IMC encounters. Just tell people to let go of the
controls, and the plane will fly out of it. In fact, that is exactly
what parachutists do if they inadvertently encounter a cloud.

Michael

Michael <usenetreplies@thisoldairplane.com> wrote in news:7dad14f5-8015-
484c-b31c-37f050dc3721@79g2000hsk.************.com:


> If the demostration is wrong, then the plane WILL remain wings level
> (the way a ram-air parachute will). Now THAT would be useful for
> inadvertent IMC encounters. Just tell people to let go of the
> controls, and the plane will fly out of it. In fact, that is exactly
> what parachutists do if they inadvertently encounter a cloud.

Some of them will undoubtedly do it, but most prolly won't.
There is one that probably would save your bacon if you had either an
engine failure or you got caught in IMC down to the ground.
It's the French Rallye and it will sit in a semi stalled attitude power on
or off as long as you hold the stick back with a relativley low rate of
descent. Some people call it the "Tin Parachute" I've flown a couple of the
small engined ones in Yerp and they're pretty marginal in climb, though..

Bertie