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Airplane parts are not always a simple fix
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You know, there is nothing like learning a new language. To be able to comprehend and articulate a foreign tongue with ease is truly a marvel. I recently picked up on a new dialect that mere weeks previous had been alien.

What follows is an actual conversation I had, during the winter of 2011. I was in the process of ordering a new alternator for my 1939 Fairchild. Simple, right?

Michael: "Thank you for calling Skytronics this is Michael, how may I help you?"

Me: "Hello Michael, I am looking for a 50-amp alternator for a Fairchild 24, with a Ranger engine. Do you have anything available?"

Michael: "Is that the L440-series Ranger?"

Me: "Yeah, square pad, three-and-a-half inch studs on center."

Michael: "You want the 6555T kit; 50-amp, 6-spline."

Me: "Is there an STC for that kit?"

Michael: "No, there is not an STC for your Ranger. However I do have some 337 forms available from guys who have gotten field approval. Would you like me to email them to you?"

Me: "Sure. My email address is delta-whiskey-echo-golf-sierra-AT-tango-delta-sierra-dot net."

If there was one thing that surprised me about the airplane restoration, it is how much time I spent on the telephone. The Fairchild was a unique enough aircraft, that sometimes it required a long-distance phone call and hour-long conversation with a total stranger in order to iron something out. Whenever something random and particular to the Fairchild arose, it was my job to start searching for someone who could help.

In this example, I was attempting to locate a new alternator. The airplane was already equipped with an engine-driven generator, but it was original to the aircraft, stamped "1940", and only rated to 25 amps. This original generator was not powerful enough to run both landing lights without tripping a circuit breaker - unacceptable.

Plus, as with any vintage generator, power output diminishes whenever engine RPMs are reduced. Remember that old car you used to drive, and how the headlights would dim at a stoplight? Press on the accelerator, and the lights would noticeably brighten. The Fairchild was the same, which is undesirable - the power needs of an airplane are greatest at a low RPM, either when coming in to land or maneuvering around the tarmac. In either scenario the lights are blazing, radios crackling, and everything turned on. The last thing I wanted was to run out of juice.

Ordering a new alternator was no mean feat, and the process was typical to the challenges that arose throughout the restoration. First, I posted a note on a special online chat group, specifically for Fairchild owners. Where do I go to get a new alternator? Within a day I received several responses, and sifted through the ones that were either irrelevant or did not pertain to my particular aircraft. Inevitably, a gem: call Skytronics.

I did, and was thus introduced to Michael, the sales rep. He asked a few pertinent questions regarding my particular aircraft and engine, and sure enough - Skytronics offered a 50-amp kit designed for use on my Fairchild. It's not over yet.

Just because the new alternator will fit, and is designed for use on my engine, I am not allowed to simply bolt it on and fly away. It is considered an alteration and must be approved by the FAA.

I asked Michael if there is an "STC" for that kit, which stands for 'Supplemental Type Certificate'. Quite simply, let's say there were thousands of Fairchild airplanes that were using this upgrade. The FAA would issue a blanket approval, called an STC, saying that ALL Fairchild aircraft of this model and with this engine were pre-approved to use the kit. In that case, life would be easy - I could simply bolt on the alternator, make a logbook entry, and fly away.

However, there has never been a Fairchild model 24, Ranger engine combination like mine to install this alternator kit. Thus, I had to seek FAA-approval in order to do the upgrade. Next, I asked Michael for a 'Form 337'. In cases like mine, there is an application (called a 337) that must be filled out and mailed to the FAA. An inspector will most likely look at the airplane, to verify that the upgrade was done according to specs. Depending on what is being approved, the process could take weeks, or months. It is not uncommon for an airplane to be completely assembled and physically ready to fly, but grounded since the legal paperwork had not gone through.

Finally, my email address is a nightmare to understand over the phone. The gibberish at the end is my email address, spelled phonetically. Works like a charm.

My alternator upgrade was fairly straightforward, and would take little time to get approved. I have, however, seen some unusual and perplexing FAA-approved modifications.

For example, it is possible to install a DeWalt cordless drill in the engine compartment of a certain airplane, for use as a lightweight starter. Hey - it's better than hand propping, right?

- Dan Wegmueller of Monroe writes a column for the Times each Monday. He can be reached at