REFLECTOR: Nose Lift

[Vance Atkinson]

doug.holub at tx.rr.com wrote:
> It looks flimsy to me, too. Like spindly legs on a stork. But I am amazed at how strong it is. It's made from solid S-glass that is post cured. I've seen it support hundreds of pounds in the horizontal position without any noticeable flexing.
>   
you are right it very strong and the advantage is unlike the velos steel 
leg, this one will flex under tremendous loads without bending.
> One complaint I've heard from Cozy owners is that it's kind of bouncy when it taxis. Because of the geometry, when the gear scissor compresses it moves the nose wheel back, which adds more weight to the nose wheel, which compresses the gear some more. So there's some positive feedback working there.
>   
Thats why you need the stronger spring, to stop the backward movement of 
the strut when loaded.  The entire nose gear must be aligned as shown in 
the picture ( about 20 degrees aft or so) to be able to taxi and castor 
easily.  And yes as the nose gear flexes and moves back, MORE weight is 
transfered to the nose wheel causing it to try and move back further.
> I've heard that Cozy owners also have problems with shimmy, 
Not if the bellvue springs are set at the proper tension. There is a 
optimum setting and above that you will not get any shimmy, but it will 
get harder and harder to turn the plane as you put more and more 
unnecessary tension on the springs
> but they don't have as much weight on their nose wheel,
The LEZ doesn't have as much weight, but the cozy with two people has 
quite a bit more.  Thats why the cozy has a heavier spring....and the 
Velo will require an even heavier spring as your main gear is further 
back, naturally adding more weight to front gear
>  so maybe it's not as much as a problem. I added a wheel lock like Ken Mishler's mostly to make sure the wheel isn't cocked when it retracts, but it might help with any shimmy problems, too.
>
>   
I built in some "guides" in the wheel wells to help align the wheel as 
it tucks up into the well.  But there is still a very slight chance it 
could go up cocked.   This scenario usually happens when taking off in a 
crosswind.  This is one of the reasons why the EZs and Cozys have a 
small window at the rear of the nose wheel cover, to see what the hell 
is happening.

Probably the weakest link of the whole unit is where the fork attaches 
to the glass strut.   So rather than bending (in the stock Velos case, 
or breaking the strut, in the LEZs or Cozys case)  the fork assembly 
separates.   Thus min damage to the fork...THEY ARE TOUGH!

Vance Atkinson
EAA Tech and Flt Advisor
COZY  N43CZ
VEZ  N3LV


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