Airframe and Powerplant

Ownership's Wrenching Possibilities

August 1, 1997

Spending your time and effort to save money

Pilots — and, in particular, aircraft owners — often complain about the high cost of flying. The plaintive wails customarily decry lofty fuel prices, exorbitant parts bills, or avaricious A&P mechanics, and yet it's a certainty that the enterprising owner can find ways to make flying a bit more merciful to his wallet. (Indeed, one of the best ways to reduce the cost of flying is to do it more often. Strictly from a bookkeeping standpoint, the more you fly your own airplane, the less expensive it is on a per-hour basis. But as a practical matter, a frequently flown airplane will be less costly to maintain because it will require fewer unscheduled trips to the shop.)

By far one of the most effective ways to cut maintenance bills is to become involved. There are, of course, different levels of involvement, and each has its own rewards and shortcomings. At the least, every aircraft owner should be maintenance aware; that is, to understand how his or her airplane normally operates and to be able to discern performance and maintenance anomalies. Further up the scale of involvement is the owner who assists in routine inspections and maintenance. (A subset of this group includes those owners who perform the allowed preventive maintenance items spelled out in Federal Aviation Regulation Part 43, Appendix A. These are tasks that a pilot may perform without direct supervision of an A&P.) And, finally, there are those hardy souls who actually perform all of the maintenance duties, using the appropriately hired wrenches to oversee the work and sign off the logbooks. Somewhere in this spectrum is bound to be a zone of comfort for you. (Indeed, a sampling of AOPA members revealed that nearly two-thirds are inclined to become involved with the maintenance.)

Perhaps the worst way to conduct routine maintenance is to drop off the airplane at the repair facility, throw the receptionist the keys, and say, "Call me when it's done." You are just about guaranteeing that the maladies you may have noticed during otherwise routine flights will not be fixed, and that a selection of items that might safely be deferred to a better time (such as during an engine overhaul, major paint job, or interior rework) will be conscientiously and expensively repaired by well-meaning wrenches.

For starters, keep a detailed squawk list in the airplane. Anything that breaks between trips to the shop should be noted and verified. Did the item stop working all at once, or did it fail gradually? Can you reproduce the failure mode easily, or is it intermittent? (One of the biggest headaches for shop personnel comes when a listed squawk cannot be reproduced on the bench.) Be detailed in your description of the failure, including the conditions of flight, location, and other factors that may not seem to mean anything but that might shed some light on the problem for a good troubleshooter. (A perhaps apocryphal maintenance story goes like this: A log entry reportedly said, "Number two engine missing." To which the lead mechanic responded, "Number two engine found on right wing after brief search.")

Prior to sending in the airplane for major maintenance such as the annual inspection, you should take the time to seek out squawks that you may not have noticed. Do all the lights work? The radios? How about the autopilot in all of its modes? Try every system in the airplane — including the emergency gear extension — and confirm that the stall- and gear-warning horns work properly. The more sleuthing you do ahead of time, the less digging around the mechanics will need to do; by necessity this is digging you will ultimately bankroll.

Take the time to carefully peruse the airplane's logbooks. Are there any outstanding airworthiness directives? Any of them recurring? Is the pitot-static/transponder check due? Are any of the engine accessories — magnetos, fuel pump, alternator, starter, exhaust system — subject to new ADs? Are all of the ship's repair and major-alteration papers in order?

Embarking upon a collaborative relationship with an individual mechanic or shop can be a delicate dance. Try to find someone who seems willing to teach, and, naturally, be ready to receive an education yourself. Outline and agree upon exactly what you will be doing during the inspection and how many of the physical tasks the mechanic is willing to let you accomplish. Even if you're pretty handy with a wrench, respect the A&P's experience by leaving your pride and boastfulness at home. There's no better way to sour a relationship than to tell the A&P how to do his job. It may be your airplane, but it's his shop — and his signature that designates the airplane as airworthy.

Now that you've done your homework — and found a willing mechanic who will let you do some or most of the work — you're ready to tackle the dirty work. Bring grubby clothes or coveralls and a small assortment of common hand tools. Good mechanics are loathe to lend tools — most would rather share toothbrushes than Snap-Ons. Have an electric screwdriver with a breakaway clutch at the ready — batteries charged and several screwdriver bits ready to go. The adjustable clutch ensures that you don't inadvertently over-torque the access-panel screws at the end of the job. If you do, the next annual will be pure agony.

As you might have guessed, the loathsome job of removing some or all of the access panels for the inspection will fall into your proud-airplane-owner hands. It's a nasty chore, but you'll get used to it. (Amazing how many owners decide that the cost of something like the smooth belly kit for Mooneys — which cuts the screw count by a factor of 10 — is much more reasonable after an assisted annual.) Plan to bring a couple of boxes of plastic sandwich bags to hold the hardware for each panel; mark each bag to identify the contents or tape it to its mating panel. Depending upon the condition of the hardware, you might take this opportunity to replace the screws with stainless-steel equivalents; they don't corrode and will probably make the next inspection easier.

Follow your spanner-boss through on some of the major inspections like the differential-compression check, control system lubrication and integrity, and engine compartment inspection. You will probably be issued the assignment of removing, cleaning, and gapping the spark plugs. Pay particular attention to the swinging of the gear, if you own a retractable. Watch a Cessna 210's monkey motion and you might well reconsider dropping the gear at the maximum-allowable speed for every arrival.

Part of any thorough annual involves removing some or all of the interior furnishings; again, this time-consuming job — one often best left to contortionists — will be your jewel. As always, take your time and ask questions if any part of the job isn't perfectly obvious.

As you develop your relationship with the wrench-in-charge, tasks and responsibilities tossed your way will blossom. For many owners, the attending mechanic is just a reference tool and an extra set of eyes and hands. (He is, of course, plenty handy when it comes time to sign off the logbooks.) Indeed, with the supervision of the appropriate person — A&P for most tasks, and one with an inspection authorization for the annual — you can legally do just about everything in the manual. The limits are really set by your abilities and available time.

Yet another advantage of working closely with the inspecting A&P involves the decision-making process. At many points in the annual, for example, the mechanic must decide whether a marginal item should be repaired or replaced on the spot, or deferred to the next annual or inspection period. You have the advantage of knowing what you'd like to do with the airplane long-term; the A&P doesn't. So, if you have a cylinder trending downward in compression, for example, but you know that in 6 months or a year you plan on upgrading the powerplant, you can save yourself a possible partial top overhaul. You can also confer with your aide on whether a new or overhauled part is best for your needs; again, your knowledge of the airplane's past and your plans for its future will help tremendously.

The other side of this involvement coin is that you cannot be an intractable penny-pincher. After all, the inspecting technician has to put his name and signature in the logbook that the airplane is airworthy. Your job in this relationship is not to nickel-and-dime him to death. He will not smile upon cost-cutting tactics that might compromise safety.

With time, you should be able to develop a relationship with a mechanic or shop that will both provide the service institution with welcome business and give you peace of mind that the inspections have been performed properly and at a reasonable cost.


The Well-Read Aircraft Owner

A good library makes maintenance easier

Becoming one with your airplane's maintenance needs requires some research. So it only makes sense that the savvy owner will have a comprehensive library of source material. What do you need?

  • The airframe, engine, and propeller logbooks. You must have these items, so what's the big deal? Well, you should spend the time to examine the books carefully, to make sure that any major alterations are backed up by the appropriate forms. And the more you know about your airplane's service history, the better prepared you will be for future maintenance events. Has the airplane had a gear-up landing requiring replacement of belly skins? In that case, you'll need to pay particular attention to the condition of these repairs. That's to ensure that no corrosion is taking place and that the fix has not shifted stresses elsewhere, causing cracking of skins or loosening of rivets.
  • Airframe service and parts manuals. For most airplanes these tomes are available from the original manufacturers; manuals for many orphaned airplanes are available through the aftermarket. (The best place to find this particular kind of information is through the type-specific clubs like the American Bonanza Society, Cessna Pilots Association, International Comanche Society, etc.) You can't properly annual the airplane without the service manual, and there's absolutely no down side to your having your own set, even if your shop has its versions.
  • Speaking of type clubs, many offer buyers' guide and maintenance materials tailored to some pretty old airframes. Because these clubs see older airframes every day and have come to understand how these models have fared well beyond the number of hours and years originally envisioned by the manufacturer, they are a splendid source of what-to-watch-for information.
  • Engine operator's manual, overhaul manual, and parts manual. The operator's manual provides significantly more in-depth information about the care and feeding of your engine than does the airplane handbook — particularly in the areas of power settings and maintenance intervals. The books also help you spot poor or incomplete past maintenance. Parts manuals are a must if you plan to do any of the parts ordering.
  • Advisory circulars 43.13 1A and 2A, titled Acceptable Methods, Techniques, and Practices and Aircraft Inspection and Repair, respectively. If you ever have a question about how to construct an aluminum skin patch properly or need to know the correct type of hydraulic fluid to use, these are the sources. Although many of the sections are outdated for most aircraft owners — like the chapter given to repair of wood propellers — the basic information is still valid and useful.

E-mail the author at marc.cook@aopa.org.