In previous commentary, I talked about what it means to be a good customer when having our machines wrenched. From respecting the techs who work hard to push the airplane out squawk-free, taking flight testing seriously, and paying the bill before you fly home—shops expect customers will do their part. But on the other hand, shops need to hold up their end of the bargain, and based on our surveys and our own experience over the years, the ones that get high marks for customer service and earn repeat business are the ones who know how to communicate and are responsive to warranty repairs. Whether it’s avionics work, engine work, paint work, or unplanned repairs, here’s what you should expect from a shop and how you might choose one.
Loyalty Matters
I’ll start by saying that if you’re happy with your shop—whether it’s an avionics or maintenance shop—why go elsewhere? It seems silly to walk away from a good experience, but I’ve also seen customers burn bridges when they really shouldn’t have. As one example, a hangar neighbor decided to try a different avionics shop for an upgrade because his buddy convinced him he would get a better deal. Sure enough, the quote was cheaper by roughly 9% (the other shop tried to steal him with a lowball number) so he walked away from a 10-year relationship with his current shop. What do you think his old shop said when he tried to schedule a pitot/static check (out of convenience) when it knew he brought the plane to a competitor for a $50,000 upgrade?
But good shops respect loyal customers. When it comes to getting work done—especially at busy shops—your loyalty might get you on the schedule quicker. “My maintenance shop showed its appreciation for my loyalty by dropping what it was doing and dragging my plane into its busy hangar when the starter failed moments before I had to make a trip,” one owner told me. When you’re choosing a shop, it’s a good conversation to have. Ask the shop if it will accommodate you should you need work done that wasn’t expected. Good shops should understand the value of a favorable customer/shop relationship, and the shop you want to go to needs to be flexible when it comes to accommodating loyal customers on the schedule. But it also needs to be straight with customers and not overpromise when it can’t deliver. As customers, we expect honesty even if it isn’t the answer we want.
Know where you stand. When scheduling work, ask the shop if your aircraft will be firmly on the schedule for a given time frame or will it be used for filler work. That way there will be no misunderstandings if the shop doesn’t get the work done when you expected.
“Just searching for the cheapest maintenance or install isn’t a route to get some loyalty back when the aircraft owner needs something done quickly,” reader and Cessna owner Scott Dyer smartly points out. If there’s anyone who knows how to keep the shop/customer relationship on the rails it’s Scott.
Cost Overruns
This is where an otherwise good working relationship can go off the rails. It might go something like this: The shop hands you a price quote for $46,500 to install an autopilot, a GPS, and an EFIS. You drop the airplane off and the shop finally calls you three weeks later to pick it up, handing you a bill for $49,800. This is completely unacceptable and it happens every day. It is the shop’s responsibility to speak up when there is labor and/or parts that are above and beyond what it quoted on the front end of the job. As a customer you have every right to challenge it if you didn’t authorize the extra work. You might have no choice to have the extra work done, but the shop still must get your approval unless you agree otherwise.
Communication is key. When accepting a “proposal” (which may be different than a firm price quote since it outlines the job but not the final price), ask the shop if it anticipates any cost overruns. In every single major job, there are items that inevitably add to the invoice, but that might be avoided to a degree by having the shop inspect the airplane before you commit to the job. Moreover, good shops might build at least some unexpected variable into the quote—and should let you know about it so you can make an accurate comparison to other quotes.
Using an avionics upgrade as an example, good shops will require that you bring the airplane to them before they quote the job so they can look at the wiring (that they can see without disassembly) and other items that might cause cost overruns. If a shop quotes a major job—avionics upgrade, a paint job, or interior upgrade as examples—without first looking at the aircraft, that’s a red flag and a setup for cost overruns.
You Want How Much for a Deposit?
A friend asked me to backstop the proposed avionics upgrade for his piston single the other day and when we started talking about the money, I sensed that he was somewhat uncomfortable that the shop wanted more than 50% of the project’s total proposed cost ahead of time, when he wasn’t scheduled to drop off the aircraft for a couple of months. Somewhat reassuring is that he’s done business with the shop before, and the shop said it would place the order for the equipment, but face it, handing over that kind of money ahead of time (with nothing really to show for) is attention-getting and concerning. But there could be benefits for paying for all of the equipment ahead of time, especially if there might be price increases on the way or if the equipment qualifies for a limited-time rebate.

I think a more reasonable payment schedule (and perhaps more common these days) is 1/3 deposit to secure a slot on the schedule, another 1/3 when you drop the aircraft off to commence the project, and the balance in full at delivery. The reality is this: Shops small and large often have cash flow challenges, especially since large projects have the airplane on the shop floor for weeks if not months. They’ll want to collect as much money as they can up front to keep the shop going—payroll, insurance, rent, equipment calibration … the list is long. For that reason, do the research before committing—and forking over the dough. Have an open conversation about the amount of money the shop is asking for. There have been plenty of customers screwed over (hard) by shops who collected money and never delivered. It’s a shame.
I recently talked about the customer’s responsibility to pay the bill before flying the aircraft home, but it’s also the shop’s responsibility to hand over a product that’s 100% functional and equipped as agreed. As an example, if the job included a major piece of avionics (maybe a secondary radio or GPS) but the shop hasn’t taken delivery of it because it’s back-ordered at the manufacturer, you shouldn’t have to pay for it until you get it. Moreover, if something major doesn’t work and that limits your ability to fly the aircraft as you normally do, a shop should be flexible and deduct some money from the bill until the issue is resolved. It’s the right thing to do, in my opinion.
Customer Comm, Visits
You can tell a lot about a shop by its willingness to let you visit, especially to check on the status of the project whether it’s engine work, avionics work, paint work—whatever. Sure, there are good reasons why shops don’t always want customers wandering around a busy work floor. There’s the safety aspect and sometimes it puts a crimp in productivity, but when planned ahead of time, there’s no reason why a shop shouldn’t spend some time with you to share progress and answer questions. In fact, many problems are avoided when a customer plays an active role in a project.

The shops that nail customer service are the ones who keep the customer informed. Face it, when the machine is down for work, we can’t concentrate until it’s safely back in the hangar. When I worked at the avionics shop, I recognized this separation anxiety and would always send the customer photos of major milestones in the project. It’s a nice gesture that shows off good work and shows that the airplane is indeed being worked on, and it’s an easy way to show a customer snags or unexpected issues that will add to the invoice. The truth is, these days where everyone is connected by gadgets, there is absolutely no excuse for a shop not to communicate. Sure, shop managers are busy—especially at smaller shops where they may be the ones doing the work—and they need to concentrate on the task at hand. But in selecting a shop, you should ask straight up how often you can expect progress updates. If a shop doesn’t seem willing to communicate with you (you might tell by the amount of time it takes for the shop to get back to you on the first contact), find another shop.
Additionally, shops should let you visit even before you commit to a project. You can learn a lot about the shop by observing work in progress. Do the techs seem happy? Is the shop floor organized and clean?
Your Pride and Joy
Good shops understand that you are trusting them with perhaps one of your most prized and costly possessions. As a result, the shop should be protected by hangar-keeper’s insurance should something happen to your machine. This is an increasingly high overhead at many shops, but it’s a must. Some manufacturers won’t authorize a shop to be a dealer for their products without insurance, and you shouldn’t leave your aircraft at a shop that isn’t insured.
It gets tricky when a shop leases space from an FBO or other third party. I’ve seen some shops work in community hangars where the FBO line staff is responsible for aircraft towing, and inevitably, hangar rash occurs. Who’s gonna pay for that smashed wingtip or the damage to repair the nosewheel because the guy towing the plane exceeded the tow limits? Ask who has the insurance should something happen to your aircraft.
Good shops treat customer aircraft as if it were their own and that means safely securing it with tiedown ropes, putting on the cabin cover (bring it and ask the shop to use it), and using control locks. I gave a friend a lift to check on his plane one windy Saturday morning when the shop was closed and when we taxied to the shop’s ramp, we found his plane sitting outside (without being tied down), no cowl plugs installed, and no pitot cover installed. Worse was the shop was installing new GPS antennas on top of the cabin and there were unprotected holes drilled that leaked rain water inside the stripped interior. That’s not how a shop should care for your bird. Pay attention to how planes are stored when you visit.
Who Flew My Airplane?!
Another friend was shocked to find that the avionics shop racked up 2.5 hours of hobbs time on his plane. It’s important that shops do sufficient ground running as part of a final test or for troubleshooting, but flying a customer’s airplane without their knowledge is a slippery slope and just bad business. If you want the shop to fly the airplane for a final test before handing it over to you, ask if it has qualified pilots to do so. While we did it all the time in the bad old days of aircraft maintenance, few shops do it today because of liability issues. Heck, many shops won’t even fly with the customer behind the wheel.
Ask the shop if it plans to ground run the aircraft and for especially complex models (turbines, mainly) if it has experience doing so. Most techs can handle running a Lycoming or Continental, but not all can safely light a PT6A. If you’re concerned about the shop operating your engine, tell the shop you can be available for the ground running.
Last, discuss ground ops ahead of time so you’re on the same page as the shop. Sometimes, it doesn’t sync, no matter how much you try. “I have a gripe with shops replacing cylinders, and then ignoring my request to not ground run the engine more than the bare minimum. The last time I had a cylinder replaced (it’s a past-TBO engine and I was selling the plane, thus no overhaul) I told the shop owner not to ground run it. I showed up, he was already running it without waiting for me, no cowling on, and definitely at higher power than required,” reader Dave Chuljian said. Unfortunately, Dave said the new cylinder now runs hot, whereas before it was the coolest. “Was it the poor break in? Who knows, but sometimes the owner should get to run the show,” he said.
When It Goes Bad—Real Bad
No matter how it happens, there are all kinds of disputes between shops and owners, and owners simply don’t pay for the work. As a final resort, the leverage that a shop has to enforce payment is to place a lien—a mechanic’s or artisan’s lien—on the aircraft. The process for a lien is almost always established by the law of the state where the shop is located, and there may be a few states that do not have aircraft mechanic lien laws. The way I see it, the best way for both owners and shops to avoid the potential for a lien is for the owner and shop to agree on terms and conditions up front and in writing. Just don’t let it go there.
But, the thing about mechanic’s liens on aircraft is that most states require that they be “possessory” to be effective. This means the shop must continuously have the aircraft in its possession after the work is done. In other words, the shop can’t let the aircraft go, discover the owner refuses to pay, and then go get it and lock it up.
The key to any good relationship is communication and the absolute best thing you can do when having your airplane serviced is to deal with a shop that understands the importance of communicating effectively with its customers. Choose a shop that gets good referrals from other customers (that had work done similar to what you’re seeking and on similar types of aircraft), visit the shop before committing to a project, and work hard to preserve a good working relationship so you don’t have to start over again.
Last, Will Fox had smart words that benefits shops and owners alike. “It is basic human nature. If someone appreciates what you are doing for them, you will go the extra yard for them.”


“I have a gripe with shops replacing cylinders, and then ignoring my request to not ground run the engine more than the bare minimum.”
Assuming the “bare minimum” includes runs to ensure airworthiness so the airplane can be returned to service, I can appreciate this take on shop obligations to customer requests. Keep in mind that what you take on as an owner/operator has the opportunity to lessen the shop’s involvement in potential warranty. Be careful here.
This line caught my eye as well, if you don’t trust that your mechanic can run up your engine properly, it’s time to find a new mechanic. More to your point, if I’m signing off engine work, I’m going to run the engine through various modes of operation to ensure there’s no adverse indications.
A ton of good advice here. Thanks, Larry.
Here’s my story of a shop flying the airplane without me.
I bought my first and only airplane, a V-tail Bonanza in November, 2001. It had an autopilot problem and I took it to an avionics shop shortly after buying it. A few months later the shop manager called and told me he had good and bad news. The good news was they got the autopilot working. The bad news was that their test pilot had forgotten to put the gear down on the test flight, had hit the prop and exhaust on the runway, and then gone around and put the gear down!
It’s important to keep vested parties holding the understanding, knowledge, and long-term commitment to your airplane project engaged in every detail of its testing. Leasing out flight test duties, albeit to highly trained and properly certificated personnel, does not always guarantee that your AP will capture and fly the approach or that your engine will meet your long-term expectations for performance, oil consumption, and operational stability. Conversely, under-rated, well intentioned flight personnel may understand the project but lack the balance expected for thorough, competent testing.
By all means, insist on joining a well-briefed flight test. It’s the best way to find a path to formal acceptance of a job well done.
And for what it’s worth, you have my sympathies for your experience.
i like content of this. thanks