Weight of metal spars?

A

aalexander

New member
On another forum, I saw somone making the comment that aluminum spar champs have a significantly lower useful load.

I'm kind of scratching my head here, is there really a substantial weight difference between wood spars and the milman aluminum replacement spars? Doesn't seem like it would be much.

Are the factory aluminum Citabria wings substantially heavier?
 
OK, I'm going to piggyback on my own question here:

How much is the gross weight increase for a Citabria if you install factory wings? I see thath te new citabrias have a 100 lb increase over the older ones (150 for the GCBG) do you get all of that with factory wings, or only some of that?

Thanks
 
The confusion stems from two factors.

1) The original weight and balance was calculated 9 out of 10 times and pretty much most airplanes never saw a scale. Witht he new wings we geneerally require the W&B to be done from scratch. We started weighing before and after when we did factory installs and found, at most about a 15 lbs gain in empty weight. Usually corresponding to a fancy paint job. More typically, expect the new wings to be slightly heavier by a few pounds.

2) For older champs, we still supply the same wing. So, the older the airplane gets, the tendancy is for a bigger loss. Reason is due to substantial structural overkill by using the same wing. New style tank supports and tanks and the thicker ribs and leading edge skin are all factors on the old stuff (pre 7GC).
 
The Milman spar STC added 10 lb to my 7ECA's W&B sheet. I didn't have the plane weighed. However, I did weigh myself. Apparently I missed a lot of meals while working in the hangar, and I lost 15 lb, resulting in a net increase in useful load. YMMV
 
Jerry,

Thanks for your reply, do citabrias upgraded to your new wings get a gross weight increase to the same max gross weight as the new Citabrias?
 
You must log in or register to reply here.
Back
Top