Hey Kevin,
Remember the parlor game where you get about a dozen people in a
circle and the first person writes a statement on a piece of paper
(which
they fold up and keep), whispering it to the person next to them, who
then whispers it to the next person, and so on; and the last person
announces what they understand to be on the paper (and it's never
even CLOSE)?
I believe I found the original source material that led up to your
query!
Go to the Ercoupe Instruction Manual, p. 4. It states that "If the
airplane is
in a power-off glide and the speed is gradually reduced by easing the
wheel back, a mild jouncing or buffeting will be noticed at about 3 mph
above the minimum speed. This is caused by the burbling of the air flow
at the juncture of the wing and fuselage, and has been designed into the
ship as an active warning that the minimum speed is being approached."
(emphasis added)
1. "Jouncing", "buffeting" and "burbling" pertain to "seat of the
pants"
sensory input...NOT a audible "stall warning device" the pilot
could
actually hear.
2. The addition of stiffeners to prevent the belly skin from
cracking,
per Ercoupe Service Bulletin 18, would have no effect whatsoever
on the above "Jouncing", "buffeting" and "burbling" warning that
minimum speed was being approached.
3. The "Model C Flight Manual" is a single sheet pulled together
subsequent to January 1, 1956, as Ercoupe Information Letter No.
2. The Ercoupe Instruction Manual is NOT a CAA/FAA approved
document.
4. There is NO published "stall speed" for ANY model Ercoupe (for
reasons previously discussed) therefore the very idea of
designing a "stall warning" system into the Ercoupe is as
illogical
as designing a bicycle for a fish.
5. The Ercoupe Instruction Manual states that "the airplane will
fly at
a lower speed with full power than without power, and the engine
might possibly fail with the airplane at less than its minimum
flying
speed without power." That's the "whip stall" I earlier warned
could
occur too near to the ground to recover.
6. It further states that "The airplane will fly satisfactorily at
minimum
speed with the wheel all the way back in a glide, but the
practice is
not recommended at low altitude because no reserve energy is
available to overcome the effects of gusty air or
mismanagement."
In reality, the vertical sink rate at a forward glide speed of 40-45
mph with the
fuselage essentially level would likely cause considerable damage to the
plane if "landed" in such configuration. Navy carrier planes are built
for such
abuse. Ercoupes are not.
The plane is NOT "stalled" in this configuration because both elevator
and
ailerons remain effective although the rate of descent is dangerously
high.
From 200-300' altitude above ground level there is insufficient
altitude to
lower the nose and convert height to forward speed in a glide. The
pilot's sole
remaining option is to apply full power. This increases air flow over
the wings
and control surfaces at an altitude where "ground effect" would assist
to avert
the disaster otherwise unfolding.
Best regards,
William R. Bayne
.____|-(o)-|____.
(Copyright 2009)
--
On Jan 13, 2009, at 14:50, kgassert wrote:
Has anyone heard that the belly of the Ercoupe was purposely designed
to flutter and make noise as a stall warning device? And that people
over the years have put stiffeners in this area to make it stop in the
believe that it was a design and in doing so disabled the stall
warning?
Kevin1
