Read my lips: When you're having avionics equipment installed in your plane, choose the shop as carefully as you choose the equipment. In fact, more carefully, because most of today's boxes perform as advertised, but a bad installation will haunt you forever. In this article, I will pass along information I have gained from personal experiences and from interviews with scores of shop owners.

Let me begin with my definition of a good installation. It is one that will enable the equipment to do everything it was built to do. The installation is well designed, panel placement is logical, antennas are located for optimum performance, and the materials provided by the shop - wiring, connectors, switches, etc. - are of high quality.

This caliber of work will not come cheap, but probably the worst mistake you could make would be to get bids from a number of shops and then choose a shop simply because it came in with the lowest price. Make your choice based on quality, and if it happens to be also at the lowest price, so much the better (but don't count on it). On the other hand, the most expensive shop is not necessarily your best choice. Those shops that cater mostly to corporate and commercial operators are likely to have a high overhead - and prices to match - due to upper-end test equipment and expertise that do not apply to general aviation aircraft.

Here are some ways in which you can evaluate the quality of an avionics shop:

Reputation. Talk to other aircraft owners, especially those who have had installations of the type of equipment you plan to buy. (That way, you'll find out something about the radios as well as the installation.) You can ask the shops to supply names of their customers. Ask these questions: Why did you choose your shop? Was the work done in a timely manner, and at the price quoted? Did you have any problems, and if so, were they resolved to your satisfaction? Would you use that shop again?

There are other referral sources. If your local FBO doesn't have its own avionics shop, ask whom they use for their training and rental aircraft; it stands to reason that they can't afford the excessive downtime that comes from shoddy workmanship. Get the name of the local field rep of the manufacturer whose products you're interested in, and ask him for referrals. He's not likely to knock any of his dealers, but he'll probably steer you to the better ones.

Personnel. The biggest complaint of the shop owners I talk to is the difficulty in getting and keeping good technicians. The better shops deal with this by offering good wages and fringe benefits, and in general looking after the well-being of their employees. In return, the owners look for people who take pride in their work and treat each repair and installation as if their own safety depended on it. Some shops also hire relatively inexperienced (and inexpensive) apprentices with the ink on their trade school diplomas barely dry. Bringing in new blood is a necessity for the industry; nevertheless, I would want to know who will be working on my job and, if a not an experienced hand, what kind of supervision he or she will have.

Impressions. When you visit the shop, what kind of vibes do you get? Are you greeted promptly and courteously? Does the person you talk to seem knowledgeable about the work you want done? Ask for a tour of the shop - behind the door that says "Employees Only." Does the place look reasonably clean and well organized? Is there a professional atmosphere? Feel free to ask questions about work in progress.

Scheduling. The chances are you don't want to tie up your plane any longer than necessary, so ideally the work will start on the scheduled day and will be finished on a date that's reasonably close to that which was estimated. Don't expect miracles in this respect; there may be some unforeseen problems lurking in the bowels of your plane, especially if the shop has not worked on it before. Also, your job may get bumped a bit if a customer limps in with an emergency. However, a good shop will be sufficiently organized and disciplined that you won't be getting a series of excuses and broken promises.

Installation warranty. The manufacturer's warranty that comes with your radio covers the equipment itself but not the installation. For example, if your nav/comm's display dies, the manufacturer will bear the cost of fixing or replacing it within the period of its warranty. But if the radio stops functioning because an external cable or connector fails, that's an installation problem not covered under the manufacturer's warranty. Each shop has its own policy on handling installation problems - generally not in writing, and often vaguely worded, such as, "We stand behind our work." (How far behind?) Some shops are more specific, offering to guarantee their installation for a time equal to the manufacturer's warranty, or for the life of the plane, or, as I once heard it expressed, "For your lifetime or mine, whichever comes first."

Bear in mind that your airplane is a traveling machine, and if a radio poops out when you're a thousand miles from home, any authorized dealer for that brand should honor the manufacturer's warranty, because he knows that the factory will pay his bill. An installation problem is something else, and the best way to handle that situation is to ask the dealer to phone the shop that did the installation and work things out.

Earlier, I suggested some criteria to use in evaluating a shop: Reputation, personnel, impressions, scheduling, and installation warranty. Let's look at some other considerations.

A shop that performs the caliber of work described above is not likely to be the lowest bidder. However, even among reputable shops, estimates on a given job can range quite widely. For one thing, shops differ in the way they price their jobs. Some have a policy of charging list price for the equipment and installing it at no extra charge. Other shops discount the equipment and charge for the installation. Of course, what you want to know is how much the total cost is going to be, regardless of how it's arrived at.

To make sure you're comparing apples to apples, ask each shop to provide as much detail as possible on the materials they will be supplying, as well as their installation warranty and any other factors they feel are worth considering.

One such factor may be a trade-in allowance on any equipment you'll be replacing. Get the shop's bid before you talk about a trade-in, otherwise they may be tempted to build the allowance into the price of the job. The trade-in you are offered will depend on the shop's policy regarding used equipment. Some shops won't handle trade-ins, period. Of those that will, some repair and resell the old boxes; others wholesale what they can and trash the rest, or keep them around for spare parts. Incidentally, many shop owners have told me that the average customer has an exaggerated idea of the value of his old radios. If you insist on getting a higher trade-in than the shop thinks the equipment is worth, they may give it to you but they'll probably find a way to make it up in the installation.

Even if the shop is charging by the hour, ask for a written estimate. I must confess that I had an unhappy experience awhile back when my entire avionics panel was redone. The project, which stretched into four months, was handled by a shop that had been doing all my radio work for years, and we had a good relationship. This lulled me into forgetting to follow my own advice. When I got the bill I was stunned. If I had maintained better communication with the shop (and vice versa), I probably would have made some other choices along the way.

If you're acquiring an IFR-certified GPS receiver, the installation in your particular aircraft must be approved by the avionics inspector at the FSDO in the shop's area. Unless you're prepared to pay for their learning curve, select a shop that has experience in the installation of and approval process for the model of GPS receiver you are buying. Ask the shop manager about his relationship with his avionics inspector and what that friendly fed demands for a sign-off. Each inspector plays by his own rules and biorhythms, and sometimes it pays to go FSDO-shopping.

Have a clear understanding of what the shop is going to provide in the way of annunciators and other peripherals, and where they will be located. If you're thinking of adding a fuel/air data system, stand-along map display, or anything else that interfaces with the GPS receiver, this would be the time to do it.

You should also expect to receive thorough training in the operation of the equipment, with special emphasis on the use of an IFR GPS set's approach mode; there is little room for confusion when shooting an approach in the soup.

Before work commences on your installation, discuss it thoroughly with the shop person responsible for the job. Make sure you are in agreement as to where the radios, instruments, and switches will be placed. If you expect to be adding specific radios in the future, consider having the wiring put in place while the panel and interior are opened up. This is also a good time to have the shop check the old wiring and replace whatever looks as if it might cause trouble.

While the installation is in progress, take the user manual(s) home and bone up on the operation of your new equipment. This is especially important if you're buying a GPS receiver; even the simplest of these units requires study.

When you pick up the plane after the work is completed, take plenty of time to assure yourself that everything is the way it should be. Check to see that everything in the panel-not just the new gear-is functioning properly; who knows what connections may have been dislodged? Run an initial checkout on the ramp, and if everything looks good, wring it out in the air. Ask a controller for a radio check. Make sure your nav equipment and your eyeballs agree. (Yes, you will be doing this in good VFR conditions.) If something doesn't look right or sound right, talk it over with the shop before you accept the job.

Be sure to get a wiring diagram of the installation and keep it in the plane; this can reduce exploration time if another shop has to work on it. Make certain all of the paperwork has been completed and signed off as necessary.

Over the years, I've dealt with good shops and some that were not so good. In the latter cases, I've had the hapless experience of bringing the plane back again and again until they got it right. Trust me, it's well worth the effort to choose your avionics shop with utmost care, have a clear understanding of what they're going to do, monitor their progress, and check out the finished job before you take your bird home.