I’ll agree with everything Bill said, below.  It matches what I’ve learned
over the years from other sources.  

 

Snubber cable advocates claim:

1.      The nose gear structure is flawed and, without the snubber cable,
the nose gear could fall off the airplane in flight.  

 

I’ve never been able to find documentation of this ever happening.  Besides,
the sissors assembly would prevent the nose gear from falling off.

 

2.      The nose gear is 1.5” too long with the double fork gear and the
nose gear shouldn’t touch ground till after the aircraft has rotated to line
up with the direction of motion, they say.

 

The original design of the Coupe’s landing gear had the nose gear extended
way down.  By the time the main gear has taken weight, the nose gear will,
almost always, be touching the ground.  Since the nose gear **turns**, it
will line up with the direction of motion and won’t provide side loads.  The
plane still rotates to line up with the direction of motion and steering is
available immediately after the instant crab-to-straight rotation.  I can’t
see that having the nose gear 1.5” longer upsets this significantly.

 

Most of all, I cite the proper authority for advocating that snubber cables
be removed.  Fred Weick himself told me they shouldn’t be on the plane.

 

Fred followed up by saying that, with the full extension of the nose gear,
with the rubber bumper installed and the fairing on the scissors to fair the
nose gear tube, their careful testing showed a speed improvement of almost
exactly 1 mph.

 

That’s just my opinion and that of the designer of the aircraft.  For what
it’s worth . . . make your own decision.

 

Ed

 

Ed Burkhead

http://edburkhead.com/Ercoupe/index.htm 

ed -at- edbur???khead.yyy       change -at- to @, remove the ??? and change
yyy to com

 

 

  _____  

From: [email protected] [mailto:[email protected]] On
Behalf Of William R. Bayne
Sent: Saturday, February 07, 2009 1:36 AM
To: ercoupe-tech
Subject: Re: [ercoupe-tech] Ercoupe Nose Gear Info

 


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)

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