Saturday, December 04, 2010

Tired, Cold, Bored and Hungry

There's a lot of intellectual and highly skilled work in aircraft maintenance. It's not all blood and cursing. Today the airplane is up on jacks and the experts are solving problems. The tasks that are appropriate for me to do are either done, not safe on a precariously balanced airplane, or would interfere with what the AMEs are doing. So I'm sitting on one of the removed airplane seats, with the brightness turned way down on my iPod in order to ration the remaining power for as long as possible. I'm alternating between games of Pac-Man (Namco, just the free demo version, high score 14680 out of a possible 14990 (I could score 15000, but the demo version only updates the high score table if I don't finish the board, so I have to leave one dot uneaten)) and making notes for the blog. So far the blog notes say "tired, cold, bored, hungry." I go to the emergency bag and put on a parka to cope with the second on the list.

Aircraft maintenance is a little like laws and and sausage, I think. It's nicer to just benefit from someone else having made them than it is to be there while the blood is flowing. Not just because you get to keep more blood on the inside of you that way, but because it can make you squeamish about the product. Pilots like to pretend to ourselves that we are the only ones in the chain who simply make the best decisions we can based on time and available information, and that somehow after we hand the airplane over to the maintainers, some kind of perfection can be produced. It's still impossible to know exactly what is going in in the airplane's innards. They do several gear swings, and my notes say "hydraulic leak, brake overflow" which doesn't sound good, it sounds as though the latter is a simple explanation for the former.

They then find something for me to do, with one of the guys asking me to, "Take all the stuff out of the nose locker." The nose locker is where a lot of the airplane specific equipment lives, things like spares, cleaning supplies, and, seasonally, deicing equipment. That I'm asked to remove it is not unusual. A lot of the avionics and the battery are accessed through there. What makes me double-take is the phrasing. "Did you say it that way to pandering to my feminine sensibilities?" I ask? He knows exactly what I meant, and concedes that he he did. No aircraft maintainer has ever before referred to the contents of that cargo compartment without employing a fecal metaphor.

They treat me well. They really do speak a different language. Not so much the conversation about parts but a non-stop stream of insulting banter to each other. They are not fighting, not even disagreeing most of the time and are working efficiently, and it's rarely offensive, but it's steadily profane. Is this all guys? It's almost aircraft maintainers, in my experience. Most of them moderate their language in the presence of customers or females, but once they relax to my presence, they revert to their native tongue. I can translate most of it.

On the way to lunch I notice a sign beside the road advertising drag racing at the airport on the weekend. I call Flight Services to check NOTAMs and find out how this will affect my ability to depart the aerodrome, but they have no NOTAM on any such activity. Maybe they won't call it in until Friday. I promise to check back, or let them know if I find out anything myself.

The guys ask me to turn on the aircraft electrical master, so I climb up to do that. My eyes automatically go first to the gear handle: training demands that I confirm the gear handle is in the down position before entering an aircraft cockpit. The handle is in the up position. I have a moment of "uhh..." before I remember that the aircraft is on jacks. Even though I know it is, because I just got in. That gets me every time.

I get out the Ice-X and clean and treat the wing and tail boots. I can't get all the way up the vertical stabilizer even with the ladder. Anyone know of anyone who died because ice clung to the very top of the leading edge of their vertical stab? I treat the propeller boots too. According to the instructions that's supposed to be done every fifteen hours, that's every day if we were flying steadily. We don't do that. I suppose we would if we were in hard IMC, or even rain every flight.

The guys have to do an impossible-looking job involving the landing gear cable. I disassemble the screens in the back of the nose compartment so they can get at it, and they work from both sides as well, apparently accomplishing their task. I get back in and confirm that I see three green and they lower it back to the wheels. There's still a chance we could have a problem with it, because it's extremely hard to test in the hangar. I don't understand all the details. There's so much I still don't know about my own airplane. I try to know everything.

My notes also say "washers." This may have been the result of delirious musings as I reassembled the nose compartment, wondering what kinds of homework assignments people got in AME school, and mentally composing an essay on the various uses of washers. I used to think the main purpose of metal washers was so that you could always have some bits left over when you had finished reassembling something, but I've come to appreciate their uses. Sometimes they are spacers, to redress a gap where the screw is too long for the thickness of what it is connecting. Sometimes it is reinforcement, where the hole is too big or the material not strong enough to be held in place just by the diameter of the screwhead. Sometimes the washer prevents damage to the paint from turning the screw. There are special lockwashers that deform as you tighten the screw down on them, so they are always pushing back against the screw, helping it not to vibrate loose. Or possibly my "washers" note refers to me dropping some under the floor and having to use guile and needle nose pliers to get them out.

We're now done except for some scat hose replacement, which can't be done today because they sent the wrong size scat hose. There is also some cosmetic work to be done on the door, but it involves disassembling the entire door, more complex than it sounds, and it's another one of those things that if they find something wrong, the airplane is grounded. We have a spare door, but there is a possibility that there is something wrong with the airframe where the door attaches. If airplanes are starting to sound like the reason you don't go in that part of your basement, you understand. Except that with airplanes it's illegal to close the door and pretend that must just dust bunnies.

We quit at 5:30 p.m., or at least I do. The guys are going back to the hotel to get ahead on paperwork, which is a huge part of their job, and a sizeable proportion of the work to be done on any inspection or scheduled maintenance task.

5 comments:

AFP said...

You do a very good job of sharing the inspection experience. I am without an airplane right now, and most days I really miss not having one. However, I definitely do not miss the annual inspection. Christmas is great because you never know what you are going to find when you get up in the morning. Annual inspections are frightening for exactly the same reason! I hope your inspection doesn't turn up any time-consuming or expensive fixes.

Wayne Conrad said...

"Scat hose?"

Ed Davies said...

Re the gear handle: while helping remove a fairly seriously damaged light aeroplane from a ploughed field I got a bit twitchy that the mag switches were still on, even though the engine was about 3 metres behind the rudder and completely disconnected. Habits.

Explaining why I was laughing at myself did, however, remind everybody that the mags would be live when we lifted the engine into truck.

Sarah said...

Yes, Wayne. Rather than risk anyone googling it, I'll just say you see a lot of the orangey slinky tubes inside airplanes. What it stands for I don't know.

This maintenance series is well timed for me. My baby in the power club is due for it's annual. If the mechanic will let me, I'll help. But he's more of the "go away and let me work" kind of guy.

PS I can't wait for the trip posts. You must have posted in a hurry, especially that last paragraph, although I do like the pure sound of the phrase "close the door and pretend that must just dust".

PPS Shouldn't stuff you take out of the nose locker be "snot"?

Anoynmous said...

SCAT appears to be a high-temperature version of CAT. My best guess right now is that it stands for Silicone Corrugated Air Tubing.

(Verification word "mamaryo" would have been more appropriate for commenting a couple of recent posts.)