Over the decades that I have been flying in and writing about private aviation the concept of remanufacturing airplanes has waxed and waned. Now the idea of remanufacturing existing airplanes is waxing again. From Cessna 152s to business jets there are now many projects to make old airplanes as good as new.
At first I bought into the remanufacturing concept. Disassembling an airplane to its barest of stud walls and then replacing just about everything seems to make sense. The components that wear or crack or corrode are gone so the rebuilt airplane should be as good as new, right?
Well, first of all, a brand new airplane is far from the most reliable. When everything, or almost everything, in an airplane has been touched, moved, installed, adjusted and tinkered with by humans the number of things that can go wrong is almost infinite. After all, that’s why prudent airplane owners insist on test flights after even pretty basic maintenance procedures, much less a total remanufacturing.
But once the totally rebuilt airplane is debugged won’t it be more reliable? I once believed that, but not anymore.
I’ve either been lucky, smart in selecting shops, or perhaps a careful observer, but I don’t need the fingers of both hands to count the number of trips in more than 5,000 hours of flying my Baron that have been delayed or scrubbed because of a maintenance failure. Yes, I have flown a few trips without some non-essential equipment functioning, but even those have been pretty rare.
The few what I would call “major” maintenance or mechanical failure issues include an engine throttle body that cracked leaving a big hole on the wrong side of the throttle plate so the engine quit at idle on taxi in, and the other was a jammed oil pressure controller that wouldn’t regulate pressure properly on takeoff after the engine oil warmed up. Both of those events happened to fairly low-time engines so an airplane rebuild wouldn’t have prevented them.
The other events that caused the rare delay or scrub all involved accessories. Once a starter failed without warning causing a delay of a few hours. The same for a magneto. I had a propeller spinner bulkhead crack but the spinner was much newer than the airplane. I’ve had an electric standby fuel pump fail. And I’ve lost count of the number of alternators and vacuum pumps replaced. Those things are like light bulbs. It’s impossible to know for sure how long they will last.
On the other hand, the significant airframe issues I’ve encountered didn’t delay flights because they were found at annual. For example, the far aft bulkhead, the one that supports the vertical and horizontal tail spar loads, was found, at annual, to have a small crack. The crack was so small it’s presence could only be confirmed by having one mechanic wiggle the horizontal while the other used his finger to feel for the crack. The crack would have eventually been serious if not found and the bulkhead replaced. And a total airframe rebuild would have found that crack. But so did the annual.
I also had a crack in the magnesium elevator, a not rare event in Barons. The crack wasn’t there, and then it was. Could a total airframe remanufacture predict the crack would form? I don’t see how.
This is a sermon that Mike Busch has been preaching to airplane owners and aviation maintainers for years. We don’t get any credit, any benefit, or more safety and dispatch reliability by replacing stuff that is still airworthy. And airworthy isn’t the same as new. It’s something that is within the tolerances of the type design.
Old airplanes are great values. New avionics add enormous capability and convenience. Often there are STCs to update the propulsion with a better engine and propeller. And new paint and interior can make an airplane look like new.
But as for stripping an airplane to the bare bones and then rebuilding it to make it more reliable, I don’t think so. Inspect carefully, fix what wears and breaks, and spend what you can afford on avionics and cosmetic upgrades and you can enjoy enormous value from older airplanes.
What do you think?