Fergus Kyle wrote:
> 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.
Sure, but if the angle is small at the pulley, you have all you need
to witness cable wear. Even if you can't see it all, and if the thing
busts FAA's 50% wear-through of two strands, and a strand or two pops,
she's still airworthy. You won't miss _that_ on an inspection, and
may even get mildly lucky before scheduled inspection when you hear of
feel something amiss in pre-flight.
> I am basing future repairs not on my life expectancy but on any
> future buyer, or either of my two sons' acquisition.
Not to deprecate airworthiness concerns, nor concern of who may fly
your bird in future, but I'm a sucker for statistics. I have years of
NTSB accident data in full relational database, including the "juicy"
fields they just won't use in published reports by NTSB and AOPA.
Total cable fracture is extremely rare, IOW, escaping simple
inspections like FAA says to do. The "juice" is that accidents here
for any mechanical cause afflict airframes with average airframe time
of over 4,000 hours! Admittedly the record for homebuilts is less
than that, but it essentially involves things informed and smart
people clearly shouldn't do, but well biased in favor of kit planes.
At least as far as control cables and such, your sons'
great-grandchildren might thus enhance their concern, except the
average annual flight time of homebuilts here is only 31 hours, about
25% less than "recreational" flying of old, aging production airframes
(avg. 29 years) - a far cry from MTBF of 4,000+ hours of the average
fleet. And after the initial test flying, they're statistically rather
safe.
Some may be interested in a homebuilt stat where if you exclude minor
incidents - but don't even bother to exclude a few instances of
plans-built planes where the builder disastrously thought a better
mouse trap, it's not just more likely - but almost certain - that a
mechanically-caused accident problem begins with the letter "F:" Fuel
delivery and Firewall Forward. Similarly, though the statistical base
for the Europa is still a bit small, but with the coincidence that
most Europas are flying in countries with the very best online safety
data - AAIB (UK) and NTSB (US) and in that order...as baseball great
Casey Stengel often said..."You could look it up!"
Best,
Fred F.
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