Your Refurb: Upgrading the Interior

One of the centerpieces of any aircraft refurb is upgrading the interior. It can be as basic as recovering the seats, but usually involves a complete redo of the headliner, side panels, carpet and upholstery. As the insulation is often stripped out and replaced as well, it's a good time to install soundproofing.

One thing to keep in mind when it comes to replacing or upgrading the interior of you bird is that you should not count on recovering the cost of the interior work when you sell the airplane—it just isn't going to happen. While the interior of your airplane may be so bad that you have to replace it just to sell the airplane, plan on only getting a percentage of that cost back in the sale.

We recommend that you do the interior for yourself—you're probably going to keep the airplane for a few years, so make it something you like and can enjoy every time you open the cabin door. That doesn't mean orange shag carpeting and Elvis velour seats—you, or your estate, is going to have to sell the airplane someday, so don't put in something that will cause prospective buyers to run away screaming.

In researching this article, we learned that there are a lot of options available for the interior, from prefab slipcovers, side panels and headliners to completely custom designed, one-of-a-kind showpiece makeovers. We also found that price and quality go hand in hand. We think that the quality of off-the shelf materials that can be installed by the owner under a mechanic's supervision. Is very good. Nevertheless, the hand-made nature of general aviation airplanes means that no two are ever quite alike so the fit and finish is never going to be as good as the more expensive work that is performed by a shop that specializes in interior refurbs.

The one thing to avoid is trying to go cheap by using automotive interior products—whether you do it yourself or provide them to a mechanic or shop. We heard too many horror stories involving everything from the result looking so bad that the owners who had to have the interior redone by an interior shop to owners who were unable to sell their airplanes because they had no burn test paperwork for the interior fabrics in the logbooks.

That being said, we've seen some beautiful interiors put together by owners working under a mechanic's supervision or under the supervision of a specialty interior shop. In most cases the materials came from Airtex, a company that has specialized in providing prefab interior materials for over 60 years.

[In picking out a shop for your interior refurb there are three basic guidelines: choose a shop that has worked on the type of airplane you own—and talk to previous customers—because you don't want to pay for the shop's learning curves on the quirks of your type of airplane; make sure the shop will take the time to talk with and work with you—there are a lot of choices to make when doing an interior and you will need to have a good rapport with the shop; and, make sure the shop will give you an estimate in writing and will agree, in writing, to not do any additional work beyond the estimate without your written approval—you don't want any surprises when it's time to pay the bill.

Once you have chosen a shop, plan on spending some time looking at fabrics and carpeting and determining precisely what work you want to have done. Partially because all of the interior materials must meet flame-resistance standards, prices start at merely uncomfortable and can escalate rapidly to "Get a bucket of water, Alice, another customer just fainted." We think a good shop should be willing to work with you on material selection, including having you buy the materials from Airtex and the shop tweaking the installation to fit the particulars of your airplane.

We spent an afternoon with Dave and Jeanne Sharpnack, owners of Centennial Aircraft Interiors on Denver's Centennial Airport. Their company has been doing custom interior installations since 1992. Jeanne explained spending time with the owner to determine what is desired and the budget is essential. She described the perils of project creep. "An owner may start out just wanting to get the pilot and copilot seats recovered. Once they're done, they make the back seats look bad, so the owner has them done. Then the seats make the rest of the interior look bad, and the owner decides to have more work done. After that, the owner decides that carrying around a portable oxygen system is inconvenient and he wants a system installed. It would have been less expensive to put together a package in the first place."

Dave Sharpnack told us that the cost for a custom interior for a mid-size single-engine airplane is usually in the $14,000 to $18,000 range. That includes headliner, side panels, carpets and re-upholstering the seats.

Once you and the shop have agreed on the work to be done and the price (it will be subject to need repairs to the aircraft should damage be found when the interior is removed—on an older airplane, the chances that repairs will be needed are very high), set up a date for the work to begin. You may have to pay a deposit; that's fine, but we recommend that you never, ever pay more than half of the price until the work is done.

The next step is to schedule the work—according to Jeanne Sharpnack, most owners schedule it to happen in conjunction with the aircraft's annual inspection. Her shop makes it a practice to work with the maintenance facilities on the airport so that annuals and interior work can be done at the same time. She pointed out that the shop may have to order materials and said that the airplane should never be opened up until the shop has all of the materials in hand. According to her, one week is usually adequate to get most carpeting and fabric, although she did showed us some very high-end carpeting that took eight months to be delivered.

Once everything is in hand and the shop begins work on the airplane, figure on three weeks for completing the interior refurb of a mid-sized piston single or twin and four to five for a turbine of the size of a PC-12 or King Air 90.

Dave Sharpnack cautioned that with older airplanes, it's common to find areas that need to be repaired once the interior has been pulled out. Often there will be corrosion where the factory sound insulation has wicked moisture against the aluminum. Seat frames and rails may be cracked or broken. When that happens, his company's policy is to immediately contact the owner and go over the options, and costs, for needed repairs.

Because aircraft seats must meet FARs for ability to withstand crash loads, repair of cracked or fractured seat structure may not be possible. There are very few people who have the appropriate certification to weld aircraft seats, so replacement may be the only alternative.

In our opinion, a shop should be willing to discuss the repair options with the aircraft owner, give cost estimates for each option so that the owner can give written assent to the specific repairs needed and then stick to the estimate. Some of the worst repair stories we've heard involve shops that inspect a little and fix a little and then inspect a little more and fix a little more.

Putting in the new interior is done from the top down, starting with the headliner. The Sharpnacks and mechanics we spoke with were unanimous in stating that the most challenging part of installing an interior is the headliner. Done wrong, it either will just plain look lousy or will fall down the first time the temperature changes significantly from the conditions extant when the installation was done, or both. We were told stories of owners and mechanics who didn't regularly do interior work having so much trouble installing headliners that they had to buy a second—or third—before they could get acceptable results.

In an article in the June 2014 issue of our sister publication, Aviation Consumer, it was reported that for less than $2000 in materials and labor, and a 10-pound increase in weight over factory insulation, you can get a six to eight dB reduction in cabin sound level in a four-place piston single. (A 10 dB reduction is a halving of the sound level.) The benefit in pilot fatigue and comfort is, in our opinion, worth it. The article indicated that greater noise reduction is available, up to 10 dB, at about twice the price.

A reputable interior shop will inspect the condition of the seat belts and shoulder harnesses, and their attaching hardware, as part of a refurb. We strongly recommend that if your airplane does not have shoulder harnesses for all of the seats, that they be installed, if possible, during any interior refurb you do, no matter how minor. The NTSB has repeatedly stated, and we agree, that the shoulder harness has been the single most successful device for saving lives in general aviation airplanes.

When the interior refurb is done, you should expect not only a logbook entry for the work and return to service, but burn test certification for the materials used. The job isn't complete until you have that paperwork in hand.

Then, call your insurance company and discuss the increased value of the airplane so that you have enough hull coverage should you taxi into the fuel pump on your way to the runway to fly home.

A reputable shop will stand behind its work with a written warranty. We think that warranty should be long enough for your airplane to go through at least one seasonal temperature change to make sure everything stays happily attached and looking nice.

We also reiterate that you should not go into an interior refurb with the idea that you'll recover the cost if you turn around and sell the airplane. It isn't going to happen. Therefore, do it for yourself and spend some time enjoying the result.

Rick Durden is AVweb's Features editor and the author of The Thinking Pilot's Flight Manual or, How to Survive Flying Little Airplanes and Have a Ball Doing It, Vol. I.