From: "Fred Fillinger" <fillinger@ameritech.net>
Subject: Re: Rudder pedal travel
> > There is another good reason to add turnbuckles in the cables and that>
> is one of inspection. With turnbuckles in the cables it is possible to> >
undo them and draw the cables forward away from the pulleys to look for> >
wear at your 100 hour checks.> > Tony
> Yes, but...one is best off in being able to adequately inspect the
> pulley and the small portion of the cable subject to wear - just
> displace the pedals. It will take thousands of hours for even an
> acceptable amount of cable wear (up to 50% of outer strands) to be
> visible. Actual troubles occur with the pulley itself, intentionally
> not made of metal - wear, loose or frozen bearing, chafing, potential
> jamming by debris. There's a basic precept in the inspection business
> that critical things not be disassembled unless at least the lesser
> evil. Doing so increases the chances, from 0%, that one day the
> reassembly, or something else critical, will be botched! Something to
> consider.> Best, Fred F.
Fred,
Quite agree. You are applying experience to Maintenance
Inspection which I am content to follow because I am a flyer, not a builder.
The practicality is that the greatest wear is probably around the pulley,
and the pulley itself. Since that doesn't move, I presume that it is not the
topic and having to inspect it is independent of the discussion. We then
move off onto the cable itself. If the motion of the pedals limits the cable
to about three inches either side of the pulley, I think mebbe the
turnbuckles allow me to move the forward area of the cable back to the
inspection panels by releasing both front pedal attachments in turn. The
portion of the cable aft of that section is more easily checked at the
panel, turnbuckles or not.
This may be exterraneous, but I have made replacement bits where
discovery of wear is most difficult to achieve. Thus cable parts can be
replaced quickly if the turnbuckles allow smaller sections of cable forward
or aft to be installed where attaching a thimble is easier, ie: aft of the
cockpit bulkhead. Or am I overcomplicating future repairs?
I am basing future repairs not on my life expectancy but on any
future buyer, or either of my two sons' acquisition. I am wary of house
owners whose repairs are based solely on their personal kismets. A
twenty-year house repair bears looking into. The aircraft can claim no less
planning.
all flames invited.
Cheers, ferg
|