Hi Tom,
I seem to recall that Erco stopped installing the nose gear fairing
with the Model G.
The snubber cable was a M10 Cadet innovation which keeps the nose strut
from fully
extending. That's fine because the Mooney has rudder pedals and a
large 5.63 sq. ft.
rudder swinging 26º left and right that is effective at low speed to
compensate for earlier
loss of nose gear steering authority taking off and delayed
availability of ground steering
authority when landing, particularly when operating in crosswinds.
Skyport sells the M10 snubber cable, and likely provides necessary
paperwork for such
installation to be "legal". Because the nose gear fairing is unable to
assume its proper
position with a snubber cable, it would act as an air scoop if left in
place. Because the
nose strut cannot extend fully with a snubber, the rubber bumper on the
scissors (or
"nutcracker" also becomes redundant.
I am not a fan of this modification for the following reasons:
1. Nose strut oleo action (shock absorption) is reduced as extension
is reduced.
2. The snubber raises cruise position of the nose wheel relative to
the air physically
accelerated by the propeller outward and behind the actual prop arc,
sometimes referred
to as "propwash". Induced drag is increased in direct proportion to
any interference to
the smooth transition of "propwash" to horizontal air flow. The speed
penalty to remove
the fairing and install a snubber is 1-2 mph, likely more for coupes
swinging 73" and 74"
props. Comparisons with and without are infinitely simpler for those
with GPS.
3. Fred Weick intended that nose wheel steering authority extend as
far as possible into
the takeoff and be available as early as possible when landing.
Ercoupe rudders of 6 sq.
ft. total area, each moving 20º outward but only 3º inward are not very
effective landing or
taking off at "minimum speed", so the extended nose wheel steering
authority and the
wing's angle to the relative wind (tail height) were materially
essential to the Ercoupe's
demonstrated ability to predictably and safely cope with high
crosswinds with a proficient
pilot at the controls.
Regards,
William R. Bayne
.____|-(o)-|____.
(Copyright 2009)
--
On Feb 6, 2009, at 20:27, THOMAS COOK wrote:
A question?? I can't find any documentation pertaining to the
removal of the nose gear fairing or the addition of the snubber
cable. Is this a legal change to the 415-C and where do I find the
documentation??
I'd appreciate any help..
Tom Couper 3989H
