Torque for prop bolts

Why are you using castlelated nuts? Does the airframe or prop
manufactuer require their use?

Diamond aircraft uses fiberlock nuts on the DA-20 C1 which uses a wood
prop on the IO-240 engine.

My glider club uses fiberlock nuts on the Hoffman 4 bladed wood prop of
a PA-25 Pawnee 250 used for towing gliders.

Both these aircraft are type certificated, if fiberlock are good enough
for them.....

If you check the torque on a regular basis as all wood prop
manufactuers I know of require than you whill have no problems with
loose bolts.

Robert Mudd
Moriarty, NM
A&P I.A.



Scott wrote:
Quick question for the group. When setting the torque on prop bolts (I
have bolts with nuts), if the hole for the cotter pin doesn't line up
with the castleated nut at the proper torque setting, is it better to go
tighter or looser to get the hole lined up. My gut instinct says
tighter, but....

Scott

I have a metal prop on a tapered crank and as far as I know, there is no
requirement to check the torque periodically. The washer fix sounds
reasonable. Now, is there a limit of one washer or is two or three
acceptable?

Scott



wrote:
Why are you using castlelated nuts? Does the airframe or prop
manufactuer require their use?

Diamond aircraft uses fiberlock nuts on the DA-20 C1 which uses a wood
prop on the IO-240 engine.

My glider club uses fiberlock nuts on the Hoffman 4 bladed wood prop of
a PA-25 Pawnee 250 used for towing gliders.

Both these aircraft are type certificated, if fiberlock are good enough
for them.....

If you check the torque on a regular basis as all wood prop
manufactuers I know of require than you whill have no problems with
loose bolts.

Robert Mudd
Moriarty, NM
A&P I.A.



Scott wrote:

Quick question for the group. When setting the torque on prop bolts (I
have bolts with nuts), if the hole for the cotter pin doesn't line up
with the castleated nut at the proper torque setting, is it better to go
tighter or looser to get the hole lined up. My gut instinct says
tighter, but....

Scott