The Pilot's Lounge #51:
Getting Your Airplane Fixed Right

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Pilots always seem to have it in for mechanics. Maybe it's a leftover from dealing with difficult car mechanics, but when a professional A&P is involved, you should work with your mechanic and not against him. As AVweb's Rick Durden discusses in The Pilot's Lounge this month, it will save you more than money.

The Pilots LoungeI could hear the noise emanating from the pilot's lounge here at the virtual airport well before I got to the door. I recognized the voice that was underway at full steam. As I considered the identity of its operator, I was reminded of one of my grandfather's favorite aphorisms: An empty wagon makes the most noise. It had been a while, but Harry, our resident incompetent, was present and holding forth volubly on some perceived injustice. Had Harry been born 30 years earlier, I would be convinced he was the model for "Dilbert," the pilot who did everything wrong in the military training manuals of World War II. (Yes, I know the name has been reused in a current, very good, comic strip; isn't it great that we authors can use ignorance of history to get away with recycling material?) I've only mentioned Harry once in this column, largely because no one who hasn't met him would believe him. He's the guy whose wife and kids won't fly with him because he makes them sick. He won't climb out of turbulence, he has no consideration for anyone's comfort, and, frankly, he's a hamfist. He yanks the airplane all over the sky and turns passengers who were once aviation aficionados into haters of little airplanes and their pilots.

I leaned against the door jam and listened, as it often turns out that the objects of Harry's indignation are folks that I'd like to have as friends.

Harry was directing his venom against aircraft mechanics in general. Apparently he'd just had some work done on his Cherokee, and he was less than happy with the bill and the fact that he dropped two grand replacing parts before the problem was fixed. Harry was busily accusing all airplane mechanics of highway robbery.

I figured there might be more to the story, so I went searching.

I wasn't sure who had done the most recent work on Harry's airplane, largely because most of the mechanics in the area have made it clear to Harry that his business is not welcome. However, we've got a new guy on the field. His name is Tony, and I suspected he probably hadn't heard about Harry, or if he had, didn't believe what he'd heard. I suspected that Tony might just have done Harry's most recent work.

I wandered into Tony's shop, noticing right away that after four months in business, the floor was still spotless, always a good sign. After a couple of pleasantries, I mentioned that I'd just heard Harry referring to work that he'd had done on his bird.

Tony shook his head angrily. "What a nightmare that guy was. He comes rolling in here right at closing, tells me he's in a huge hurry and that he's getting a lot of vibration. He tosses me the keys and leaves. I can't get to it until about one the next afternoon, but by then Harry's called three times saying he's got to have the airplane and he's sure it's a bad mag. I try to get him to describe the circumstances when he's noticed the vibration, and whether he can tell if it comes from any particular area in the airplane so that I can start troubleshooting. As soon as I say troubleshoot, Harry goes nuts. He says mechanics do that just to run up the bill and he doesn't want me wasting his money troubleshooting because he knows for certain it's a bad mag."

Mechanic and Piper

Tony poured some coffee from a Thermos, grimaced and continued. "I do an engine runup and there is some vibration that shouldn't be there, but it doesn't feel like a mag to me; plus, it stays the same whether I'm on the right, left, or both mags. They both check out fine. After I shut down, I get called to the phone again. It's Harry asking whether I'm done. I tell him the mags check out and again try to get some information out him about the vibration. No chance. Harry tells me in no uncertain terms that it's the right mag and he wants it replaced. I try to tell him the mag is okay but he isn't having any. I put in a new mag. No change. I call Harry and tell him. Within seconds he's decided that it's got to be the carb heat muff and he wants it replaced. I pull the cowling and check the entire carb heat system for security. It's fine. I tell Harry, but he wants everything replaced. So I do it. No change. Before I can do anything else, Harry's on the phone with a new theory. It goes like that on and off for three days before I can pry out of him that the vibration is worse at particular power settings in flight. I finally tell him I'm going to fly the airplane and do my own diagnosis. You'd think I was going to stick a gun in his side and demand his wallet, the way he reacts. He doesn't give in until I tell him I'm not working on his airplane until I fly it and check it for myself. Sure enough, the vibration in flight is very distinctive. I've felt it before in a Stearman where one prop blade was twisted slightly due to damage. Back on the ground I did a little measuring and one blade was bent aft a little bit."

Tony took a minute to finish off his coffee, looked at me and said, "I call Harry and told him what I'd found. You know what that genius told me? It seems he generally pulls his airplane out of the hangar with his car using a rope attached to the bumper and the tow bar. The other day he stopped quickly and one blade of the prop tagged the rear bumper of the car. He didn't bother to tell me. I sent the prop out to have it straightened, which wasn't too expensive, and I told him that the engine manufacturer calls for a teardown inspection if there is an impact that bends the prop. Of course he says there's no way he's springing for that nonsense, as he put it. So, now he's used ten hours of my time and paid for a bunch of parts for a job that I could have done in one or two hours if he would have just talked with me a bit. On top of that he's really angry at me because I wouldn't let the airplane go until I'd filled out the logbooks and he paid me. I thought he'd have a coronary. Harry goes up and down telling me that I'm a new guy and I've got to learn that the practice around here is for mechanics to simply bill him for their work. I told him that I'm just like the car repair shops in town, you gotta pay when you pick up the airplane."

Tony smiled, "I guess Harry didn't really need the airplane all that much. He stomped out of here, so I pushed the airplane outside, tied it down, and put a prop lock on it. It was three weeks before he came back and paid his bill so he could get the airplane."

A Fundamental Disconnect

Mechanic Training

Listening to Harry and Tony reminded me of how much money and time is wasted in the process of fixing airplanes because, too often, there is a fundamental disconnect between pilots and mechanics. It's been a problem for years, and I wish that more private students would get 15 or 30 minutes of instruction on how to write up a squawk on an airplane, or how to effectively communicate with a mechanic about a problem that is observed in flight. Better still, students should buy a half hour of a mechanic's time and sit down and talk over what it is a mechanic needs to know from a pilot in order to properly diagnose the ills of an airplane. While it's only my opinion, when there is a disconnection between a pilot and mechanic in the process of trying to fix a squawk, I tend to side with the mechanic on the issue of who slipped up. Mechanics are the professional airplane fixers; pilots too frequently are amateur communicators.

"Uh, I Didn't Mean To Say That"

On one level, the inability of some pilots to write coherent squawks can be humorous. We've all seen the piece on the Internet listing squawks supposedly written by pilots and the follow-up entries by mechanics. Probably the oldest starts with something along the lines of "Number two engine missing." Of course, the corrective action written in by the mechanic is either "Number two engine found on right wing," or, "Number two engine found and put back on." While that is an exaggeration, the things written by pilots on squawk sheets can be pretty useless. "Airplane runs rough" just isn't calculated to give much guidance to the poor schmuck who has got to figure out what it means and fix it.

Naturally, there have been errors in the other direction. When I was flying freight during law school, an acquaintance of mine working for another outfit got more and more exasperated one winter over the failure of the operator to fix the heater in the airplane he regularly flew. He finally took a thermometer with him on a flight. He wrote up a yet another squawk on the heater, noting that the cockpit temperature was about 18 F at altitude. Some mechanic wrote in the follow-up column "wear a coat." (This was in the days when the FAA looked the other way with regard to the on-demand freight business.) The pilot hit the roof. He knew the systems on the particular airplane and was aware that, below 40F, the gyros were not considered reliable. He had some, ahem, frank words with the mechanic, because the pilot was flying hard IFR and his life depended on those gyros. It so happened that the mechanic didn't know about the limitations on those gyros and, because the mechanic was doing maintenance out on a cold, windswept ramp, he just considered the pilot to be a whiner and he'd fix the heater after he took care of other items he considered more pressing. Even though it was not pleasant, the face-to-face communication between the two allowed the problem to be solved.

A Little Expert Input

Air Force Mechanic

I don't pretend to be an expert in doing the right things to get an airplane fixed, so I called a couple friends, Michael Cook and Ace (no, I'm not kidding) Glidewell. Michael is the maintenance manager at Rapid Air, an FBO in Grand Rapids, Michigan. He's one of those guys with the kind of reputation that causes pilots to travel a long ways to have him work on their airplanes. He spent some time early in his career in the Air Force, and has twisted wrenches on some pretty exotic stuff such as the SR-71, as well as a few experimental birds out in the desert at Edwards. He has some fond memories of General Chuck Yeager showing up to get his hands dirty with the enlisted guys as they prepared an aircraft for a flight test. Ace Glidewell works with the School of Missionary Aviation Technology in Lowell, Michigan, and has spent a fair amount of time in interesting locations making sure little airplanes would reciprocate when needed.

Rules 1, 2 and 3: Communicate With Your Mechanic

Michael has seen the good and bad in trying to troubleshoot airplane problems. He learned long ago that communication between the pilot who experienced the problem and the mechanic assigned to fix the airplane is utterly and absolutely essential to finding out what's wrong with an airplane and fixing it in a reasonable period of time. He still recalls a frustrating experience early in his career when working on a two-seat F-100 in which the squawk he had to attack was "oxygen system smells like bananas." The pilot was making himself scarce, and Michael spent several frustrating days purging the system and trying to duplicate the problem. Finally, he located the backseater and learned that the smell only occurred when the flow was at 100% and the airplane was at high altitude for a period of time. With that information and knowledge of the positioning of a diaphragm in the regulator, as well as the fact that a portion of the interior of the regulator was painted with a banana-oil-based paint, he was able to determine that the paint hadn't properly cured and was off-gassing. Replacing the regulator solved the problem.

Michael and Ace could not emphasize enough the need for pilots to take the time to communicate with the mechanic, whether it be in writing or verbally. If you want your airplane fixed correctly in minimum time, write down a squawk that makes sense as soon after the problem occurs as possible, and then talk to the mechanic personally with the written squawk in front of the two of you. According to Michael, terse squawks such as "I pull the lever and it don't light up" aren't exactly models of effective communication. If you as a pilot notice something amiss, write down what is wrong, and then write down the time, altitude, outside air temperature, power setting, oil temp, oil pressure, cylinder head temperature, indicated airspeed and anything else that you can think of that might be relevant to the situation.

Know Thy Airplane

Autopilot Switch

Michael and Ace were reluctant to bring up the next point for fear of insulting pilots. They both were very polite when they said that it helps tremendously if pilots know the systems of the airplane they are flying. We've all heard the story about the pilot who squawked the auto-land function of the autopilot on an airplane as causing very firm arrivals, and then was told that the auto-land function was not installed on that airplane. While that is probably an urban myth, a certain number of squawks are written either because the pilot does not know the particular system on the airplane and was operating it wrong, or doesn't know enough about it to write up a coherent squawk. Yes, pilots operate systems improperly and then squawk them as not working; it seems to be most common with autopilots because, for some reason, pilots rarely get checked out in their operation and don't read the autopilot manual. Michael said mechanics don't expect pilots to be mechanics, but it helps tremendously if the pilots know how many fuel tanks the airplane has, or, for example, that the landing-gear handle on an Apache returns to the center position after the gear has completed its cycle, and doesn't stay in either the up or down position.

Be Descriptive

If there is time once a problem is noticed in flight, write down as descriptive a squawk as possible. If it's vibration, try to determine the general area of the airplane it's coming from, then see if changing a variable affects it. Does altering the propeller rpm change anything? What about shutting off one mag? To the extent you feel comfortable, and only to that extent, change some variables (one at a time), and write down the results. Even little things may help a knowledgeable mechanic get a handle on the problem.

Electrical problems and vibration are the squawks Ace said are toughest for a mechanic to solve. The more information about the nature of what you experienced in flight, the better.

Let Your Mechanic Troubleshoot the Problem

One of the most effective ways to increase your maintenance bill is to prevent your mechanic from troubleshooting the matter. Give him or her as much background information as you can and then step back and allow troubleshooting to take place. According to more than just Michael and Ace, a small portion of aircraft owners insist they know what is wrong and demand that the mechanic look at that system or component first, to the exclusion of all else. Of that group, a frustratingly high percentage is in error the vast majority of the time, and they pay for it. If you are one who usually tells, not suggests, a mechanic what's wrong with your airplane, and if it was not what you said twice in the last four times you were in the shop, you're one of the problem children. So, provide background and than shut up, because your "helpful" ways are costing you money.

History

If the mechanic doesn't know the airplane well, be certain to provide the logbooks to him or her along with the airplane. One of the techniques used by a good mechanic to troubleshoot is to examine the logs, because there may be a pattern that suggests something, or there may be an unperformed Service Bulletin or Airworthiness Directive that is right on point.

Did You Try To Fix It?

Tell your mechanic if you have tried to fix the problem. One of Michael's classic experiences involved a squawk stating that a nav light was out. The bulb proved to be fine, but it wasn't getting power. Chasing the source of the power loss took hours. It turned out the pilot had himself troubleshot the problem and, correctly, found a broken wire. He used a clip to splice the wire back together. That should have fixed the problem, but he omitted one little step. He didn't strip the insulation off the wire. Oops. Those little electrons just wouldn't flow. Had the pilot mentioned his well-intentioned "fix" the repair would have taken less than an hour. As it was it took nearly all day before Michael found the spot where the clip was inserted and determined it wasn't conducting electricity.

Paperwork

It is not legal to fly your airplane after repairs until the logbook entries have been made. I don't know how many pilots forget this immediately after reading the FARs when working on the private rating. Don't go charging out of the shop with a casual, "Fill out the logs when you have time, I'll pick them up later." The chances are getting better and better that you will get caught. The FAA is looking at the records of mechanics, and is checking aircraft and airframe logs as part of those inspections. Pilots are getting nasty little notices of violations for flying their airplanes before the logbook entries were made. It is the responsibility of you, the pilot in command or the owner, to determine that the maintenance work has been recorded. Yes, you are the captain of that ship: If there's something missing, you are the one on the hook. So, if you don't have the logs, make sure the mechanic writes up the entry on a sticky label before you fly the airplane. That way you can put the entry into the book when you get home. Then do so.

A Few Suggestions

Preflight

Don't you love it when you load the family into the airplane at 5:30 Friday evening for the trip to grandmother's house, and your steed can't make it through the pre-takeoff check? You've been there, right? Either a mag wouldn't pass muster, or the carb heat didn't do its thing, or something else caused you to go searching for a mechanic on a Friday evening. You quickly learned that you would be more likely to be successful at a snipe hunt.

I like Ace Glidewell's suggestion. He asserts that most of the time, the thing that wore out or isn't working actually quit on your last flight. As a result, he teaches pilots to do a quick engine runup check following each flight and then to do a preflight on the airplane after shutting down. It usually means the problem is uncovered when there is time to fix it before the next flight. It sure sounds like a good idea to me, and I've added it to my post-flight procedure.

A point of etiquette when you are in the shop: If a mechanic is working on your airplane and you need to get something out of it, don't just hop on the step and charge into the cabin (particularly if it is on jacks). You will rock the airplane. Mechanics concentrating on close work have been hurt because movement of the airplane jammed something into their faces. At the very least, they are unpleasantly surprised. So, ask permission before you leap.

A Few Suggestions For Mechanics

I've been pretty hard on pilots and their shortcomings. As hard as it is to believe, there are some mechanics who aren't perfect. For those few, I ask that they be willing to take the time to talk with pilots and listen to them, because most pilots honestly want to get the airplane fixed correctly. It may pay off by making your life a little easier.

If you are a mechanic who doesn't like paperwork and perhaps has a tendency to let it slide for an hour or two, or even several weeks, after buttoning up the cowling, you might want to reconsider that practice. Sure, you've let owners take their airplanes because the invoice and logbooks weren't written up yet. But, you passed those writtens for your A&P, and you know that an integral part of any repair work or return-to-service is the logbook entry. In fact, the work is not technically complete until written up. I'll pass along a little something: The FAA is violating mechanics when airplanes get flown before the logs are filled out. It isn't pretty. You might want to start completing the paperwork before you let those airplanes be flown. I know of two mechanics who have an interesting, and to me, very appropriate, technique for dealing with this subject. When they are getting near the completion of some work, and before the cowling is reinstalled or the aircraft is otherwise buttoned up, they stop. They then go through a mental checklist of everything that was done, physically put away all tools they will not need for closing things up, and fill out all the paperwork. Then, and only then, they put the cowling back on or otherwise close up the airplane. It allows the paperwork to be done and it also allows for a few moments of mature reflection about the job, to assure themselves everything was done correctly, nothing was left disconnected, and no rags or tools were left where they shouldn't be.

Finally, it is my opinion, based on working on owner-assisted annuals, that aircraft mechanics work hard for what they are paid. (I happen to know that many of them make less than auto mechanics who haven't received a fraction of an A&P's training and don't have a hundredth of the responsibility.) Yet, many of those mechanics who aren't being paid all that well proceed to make it worse on themselves. I constantly see small shops where the mechanic has been stiffed by about 20% of his customers who either don't pay or pay very slowly. It is my opinion that no mechanic should release an aircraft following work until payment is made. I've seen it time and time again, and I've said it before: Pilots are notorious tightwads. You there, Mechanic don't let that airplane go until you get paid. There is a mechanic shortage, so what if you lose a customer if you insist on payment at the time the work is done? Who needs customers such as that? You aren't licensed as a bank, why make zero-interest loans to deadbeats?

Spotting A Good Shop

When you are away from home plate and need work done, is there any way to tell if the shop is any good? For some reason, an old rule-of-thumb continues to hold pretty true. It's not perfect, but it's right a surprising amount of the time: Look at the floor. The best mechanics seem to keep their floors spotless. It seems to be more accurate than any blanket recommendation to either patronize or avoid small shops or large facilities. I've seen one-person shops that were great and ones that were criminally bad. I've seen large shops that do excellent work and ones where I'd take a turbine-engined airplane, but I wouldn't let them work on a piston-powered airplane under any circumstances.

"What We Have Here ..."

It really boils down to communication when you want your airplane fixed correctly. Record as much information as you can when something malfunctions, take time to discuss it with your mechanic, and then let the mechanic have the uninterrupted time to get to the bottom of the problem. The money you save may be your own.

See you next month.