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Old February 11th 04, 08:32 AM
Kees Mies
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Marty Shapiro wrote in message ...
(Kees Mies) wrote in
om:

The Socata Rallye has a stall warning!
Their famous automatic leading edge slats are it.
At least, that's what I use them mainly for. They are great speed
brakes too.
I do not pay much attention to the air speed at take off or on short
final.
When I see the leading edge go forward about 4 inches from the corner
of my left eye, I know it is time to have a look at the dials.

To my opinion these are the best stall warnings one can have.
Instead of a lot of noise(a Rallye is noisy enough) and some red
light, they keep the stall away for about 15 kts.
This said, do not try to flare a Rallye at too high speed.
The slats pop out and you go up again.

And they keep the Socata leading-edge-slat-roller-division going.

Regards,
Kees
MS880B


Marty Shapiro wrote in message
...
Roy Smith wrote in news:roy-
:

Researching a question from a club member, I read in the FAR's:

§**23.207 *Stall warning.
[...]
(b) The stall warning may be furnished either through the inherent
aerodynamic qualities of the airplane or by a device that will give
clearly distinguishable indications under expected conditions of
flight.

Every plane I've ever flown has a mechanical stall warning device
(some visual, some aural), but apparantly it's possible to certify
a plane without one. Does anybody know of any real life examples
of planes certified without stall warning devices?

The SOCATA Rallye does NOT have a stall warning device!

It has automatic leading edge slats which will pop out at larger
angels of attack, but you are still well above stall.

A power off stall is very interesting in this aircraft. You start to
get stall buffett and, if you simply hold the yoke all the way back,
you descend a little over 1000 fpm with the nose level on the
horizon. You can turn with just the ailerons as you are descending.



Under the definition of stall warning in the US FAR §23.207 (which
references §23.1185), the automatic leading edge slat deployment is NOT a
stall warning.

Although the automatic leading edge slat deployment meets the requirement
of §23.207(c) where warning is required at least 5 knots above stall, it
does NOT meet the requirement of §23.207(d) "When following procedures
furnished in accordance with §23.1585, the stall warning must not occur
during a takeoff with all engines operating, a takeoff continued with one
engine inoperative, or during an approach to landing." 23.1585 refers to
the required aircraft operating procedures which include Vx, Vy, etc.

In the Rallye 235E, the slats will automatically deploy at rotation and
remain deployed at both Vx and Vy. As you transition from Vy to cruise
climb, they retract. They also deploy on landing at about Vref. At Vx, Vy,
and Vref, the automatic deployment of the leading edge slats violate the
FAR requirements for a stall warning.

The slats will sometimes extend & retract in light chop at cruise speed (Va
and above). I've never had a stall horn in a Piper or Cessna sound off in
light chop.


Hi,

Nice research.
I did some myself.
Under KEES' FAR §58112.fgg(c) is stated:
The installation of a stall warning device has NO relationship with
the pilots'/operator/owners' sense of humor.