Economics and Human Fallibility

I do the maintenance for an Aero Club and bill a modest hourly rate. A few weeks ago the alternator brushes gave out in one of the Cessnas so I took the alternator to a local shop & they put new brushes in & I put it back onto the airplane. I also installed a noise filter (capacitor) while I was at it, which necessitated finagling with the orientation of the filter, its lead, and the battery, field & ground leads because that alternator is jammed between the cowling and the baffling and there just isn't a spare square millimeter to pack all that stiff wiring into. I took me about three tries to finally get it all to fit without chafe points and all wiring still slack.

Shortly afer completing the installaton I noticed the ammeter oscillated like a fan at low RPM but seemed to steady up at higher power settings. The airplane flew for a couple weeks and the oscillations stopped. Whatever it was seemed to have corrected itself.

After forty years futzing with things mechanical I should have known better. Sure enough late Friday afternoon a pilot called stranded at the fuel ramp. Dead battery. Well, that explained the lack of ammeter oscillation: the last few hours had been flown on the battery only. Fortunately you can hand start an airplane engine (they run on twin magnetos, independent of the electrical system), so I got the thing running and got it to our hangar and in half an hour had the alternator on the bench and the answer in fragments beside it: the remains of the battery terminal post, burnt clean off (along with the terminal ends) by the blowtorch of high voltage arcing. The nut holding the battery lead on hadn't been tightened when I'd installed it, creating momentary breaks in contact that the regulator overcame by upping the voltage until arcing completed the circuit. My mistake. I realized that all those trials getting the leads secured properly distracted me enough I'd forgotten to tighten the terminal nut once I'd succeeded in getting it all to fit. Dumb.

It was just a week ago I'd told another airplane owner I'd helped get his carburetor put back that 60 percent of what a mechanic does is simply repair what he's f---ked up. How true.

So here's the 100 dollar question.

Do I bill the club for my labor putting the alternator right? Should the club reimburse me the $65 it cost to have the alternator shop replace the burnt terminal and bench check both the alternator and the regulator?

My ethical mind says no - I goofed, I should pay.

But that same ethical mind says yes, man is fallible; we will always goof, and allowance for the inevitable goof is a cost that should be borne by all of us. The rate I charge the club is modest, less than standard shop rates by more than half. There is no cushion in the rate to serve as a goof allowance (which is part of the reason shop rates are as high as they are, I'm sure).

I could bill the club only half, and eat the other half.

Last year I changed a tire and pinched the tube doing it; but the tire didn't go flat until the airplane was at another airport, and that sheer remoteness added $200 to making the fix. At the time I tried to bear those costs myself but the club's maintenance officer said don't be ridiculous, my mistake or not, it was routine club maintenance and the club should pay the full bill, including mine.

I'm sure he would insist the club pay the full bill in this instance too.

So - what are your thoughts?

 

Thanks for all the insightful response. I'll likely introduce our maintenance officer to this thread and we'll discuss. I have to say, the power of the Internet to furnish exactly these kinds of exchanges is an amazingly constructive new social force, for it proffers perspectives from a vast diversity of experience unattainable (and often impractical) from other more conventional community forums. It's one reason I despise trolls with the intensity I do - they only corrupt and corrode this marvelous new tool for strengthening and increasing our general understanding. So many thanks!

Just after writing my OP I realized I may have given the impression I'm all thumbs with the wrenches. While I'm sure opinions may differ, for what it's worth the Aircraft Inspector I work with has more than once said that when Baird repairs something it stays repaired. To my mind the dangerous mechanic (or other operator) is the one who doesn't do personal and honest post-mortems, who really does think he's infallible.

I may also have given the impression that light aircraft maintenance is casual or haphazard. While it's true that we don't maintain light aircraft to the same standards as airliners (if we to tried no one but Bill Gates could afford so much as a Piper Cub), it is nonetheless a stringently regulated field where just getting the basic licenses takes several years. There's substantially more to know than basic mechanics - even the most intelligent mechanically astute person would without training commit legal sins, like routing an electrical line beneath a fluid line, or putting a self-locking nut on a hingepin bolt, among many other arcanities of aviation maintenance learned and applied only after someone's blood got spilled.

But until we program robots to do it for us, we'll continue to make mistakes, even stupid mistakes - out of ignorance, fatigue or just plain bad luck. It's the price for going beyond nature and inventing our own contrivances. The smart ones (I hope I'm one) try to prevent them to begin with, by adding systems for catching errors, such as checklists, but especially by being ruthlessly honest in assessing them when they happen.

Thanks again.