SERVICE SUGGESTION

In a recent e-mail message from a Glasair RG builder, I was told about an

incident he had experienced while landing, in which the nose wheel had

become detached from the nose wheel fork. He was unsure as to why the nose

wheel axle had become detached from the nose wheel fork since the nut on the

axle bolt is visible whenever the toll bar is used on the nose wheel. I

suspect, either then nut had been over-tightened, damaging the internal

threads, or perhaps the builder experienced nose wheel shimmy and the side

load on the nose wheel fork caused the nut to fail. This would then result

in the axle becoming loose, allowing the nose wheel and axle to separate

from the fork.

When assembled according to the instruction manual. The nose wheel axle is

held in place within the nose wheel fork by an AN4-56A bolt and an

AN364-428A nut. This AN364 –428A nose wheel axle nut is a shear style fastener. The use of

the larger, tension style AN365 – 428A nut is not practical in a Glasair I

and II installations since nose wheel box clearance can be very close in

these aircraft. The nose gearbox on the Glasair III is wider, but it also

can be close depending upon the fire barrier installation.

It is possible to get the strength advantages of the tensions style nut

without going to the larger sized AN365-428A nut by using the MS21042-4 nut.

This nut offers a very high tension strength of 6200 lbs. The AN364-428A nut

is rated far lower than this.

Because of the minimal cost and labor involved, I would like to suggest that

thisMS21042-4 high strength nut is a very inexpensive upgrade to your nose

wheel installation. Aircraft Spruce and Specialty Company does carry this nut. Newglasair does

also carry this nut and can supply it. Please be aware, however, of our $15

minimum order fee.