Parts manufacturer approval: Private parts.
Airplanes need replacement parts, that much is certain. But with the fate of some airplane manufacturers — from which most model-specific parts come — as uncertain as tomorrow's fashion, owners are having to ask tough questions about the future support for their mounts. It's no longer a matter of only calling on a Cessna or Piper dealer for the parts. The replacement in question might not be available, or it may be prohibitively expensive. One recent story recounted to us comes from the owner of a single-engine Cessna. It seems the stall-warning switch in the wing failed, and he was quoted $1,800 for a replacement from a Cessna dealer; he found one elsewhere for $1,000.
You don't have to be a shrewd businessman to understand what that kind of pricing philosophy does to supply and demand. Right now there is demand for replacement parts, items that the airframe factories either cannot produce or are, in the opinion of many owners, exorbitantly priced. At least some of the supply of airframe and engine replacement parts has been coming from and will in all likelihood continue to come from entities independent of the original equipment manufacturers (OEMs).
An FAA-administered parts manufacturer approval, or PMA, enables a company other than the original manufacturer to produce and sell these replacements. In essence, the FAA intends that the parts work just like those from the OEM. The FAA breaks down the part conformity as form, fit, and function. Generally, it is easier for an OEM to produce replacements, and much of the PMA slalom course is marked by posts consisting of traceability of materials and fabrication. Simply put, the FAA wants to know where the raw materials came from, who put them together to make the part, and who inspected that part prior to shipping; it's up to the PMA parts maker to schuss down this slippery slope of paperwork.
Ultimately, you and your mechanic are responsible for determining if a replacement part is suitable for the airplane. You should determine its origin, estimate the suitability of design and materials, and ensure proper fit and function. FAR Part 43 sets down broad guidelines for mechanics on maintenance and repair of certificated aircraft; the rule says, in part, that the mechanic should "...use the methods, techniques, and practices prescribed in the current manufacturer's maintenance manual or Instructions for Continued Airworthiness prepared by its manufacturer, or other methods, techniques, and practices acceptable to the Administrator...." These practices include determining suitability of replacement parts.
There are several ways to legally install parts not supplied by the original airframe maker. You can apply for a Form 337 field approval, and place yourself at the mercy of your local Flight Standards District Office. (Thanks to the FAA's hierarchy, each office approaches alterations with a slightly different attitude; one region might be generous in approving a particular alteration while another could outright refuse the same one.) Parts can also be substituted if they and your airplane are covered under a supplemental type certificate approval. You still must proffer the appropriate paperwork to the local FAA office before the airplane can be returned to service.
Another option is to install FAA-PMA parts. Ideally, there should be no paperwork hassles here because the parts have previously been approved for installation on your airplane and are considered interchangeable with factory- supplied parts.
Detailing the process of going from an idea (of producing replacement parts) to actually being able to sell something is like describing a long and torturous road.
According to FAR 21.303, "...no person may produce a modification or replacement part for sale for installation on a type certificated product unless it is produced pursuant to a Parts Manufacturer Approval issued under this subpart." The exceptions to this rule include "parts produced under a type or production certificate; parts produced by an owner or operator for maintaining or altering his own product; parts produced under an FAA Technical Standard Order; standard parts (such as bolts and nuts) conforming to established industry or U.S. specifications."
To see the PMA playing field from the other side of the fence, we talked to Ken Rickert, owner of Globe Fiberglass in Lakeland, Florida. His company began by supplying replacements for Piper plastic wing tips and fairings. At first the company competed directly with Piper, and then, when Piper's financial woes caused a reduction of parts production, Globe became the ally instead of the enemy. Rickert and company have since begun providing parts for many other makes as well as working with the Commander Aircraft Company to provide various parts for new 114Bs. With more than 400 part numbers on the corporate spreadsheet, Rickert has seen the PMA process from the inside many times.
"It takes tremendous blood, sweat, cash, and paperwork to get a PMA," Rickert says. He relates how the company must put the cash up front, do all the engineering, and not advertise the product for the duration of the PMA approval process, one that takes anywhere from a few months to nearly two years. He says that a PMA manufacturer can do well, "feed the kids, pay the bills," if overhead is kept down and the paperwork has every "i" dotted and every "t" crossed. He agrees that PMA parts suppliers will take an ever larger role in keeping the fleet out of the boneyard.
The guidelines for receiving a PMA are listed in FAR Part 21 and are as formidable as a medieval-history midterm. In fact, the requirements placed on the PMA supplier have led prospective entrepreneurs like so many mice to the underground, making unapproved parts. These parts could be as good or better than the factory equivalent, but without PMA, the companies producing them cannot legally sell them for installation on production aircraft. Still, unapproved parts are built and installed every day — it happens.
Let's say you have selected the replacement parts on which you can make a profit — you wouldn't get into this to lose money, would you? If your intent is to duplicate the original exactly, then you need to find or buy an example. From this part, you take the dimensions and probe into its construction and materials. Let's say that, as in Rickert's case, you are taking a plastic wing tip and producing a replacement in fiberglass. Once the molds have been set up and you have produced a prototype, you begin the engineering to prove that your part is as strong or stronger than the factory piece, and that it will not interfere with any other part or system once installed.
Then you must go to the FAA with an armful of pertinent information like the location of your factory, the design specifications of the part, materials, dimensions, results of stress tests, and so on. In other words, you must go back and prove to the FAA that the part you are making is for all intents and purposes as good as (or better than) the original.
Assuming the paperwork passes muster, you can expect the FAA to stop by to inspect the production facilities and quality assurance program. You are also required to freeze the design between the time you receive initial approval on the paperwork and when you deliver a completed part to the FAA for testing. After all this, you must set up a quality assurance program, and you must keep track of the parts and maintain files on all of the above requirements for two years.
Although lengthy, the process seems at first blush straightforward. But there are myriad traps. Rickert describes one of them: Changing material, as with some of the plastic parts, can cause fits. The manufacturer is then required to prove conclusively that fiberglass will do the job where the original maker specified plastic. Constructing, as Rickert's company does, nonstructural parts has made the job somewhat easier but by no means a cakewalk. Rickert and crew are embarking on production of retrofit fiberglass nose cowlings for Piper Comanches; this part, by the way, has recently been reclassified by the FAA as a structural component.
Another pitfall might be the efforts of the original manufacturer to block approval of the PMA for obvious fiscal reasons. There are some cases where the company applying for the PMA needs to have access to the original part's blueprints; this is generally not possible when the OEM is still doing business. In this case, and to prevent being sued for stealing the design, the company must change the design just enough to make it different but leave it close enough to the original to please the FAA. This can be a real tightrope walk. And even if successful, the company might find that the OEM has slashed prices to compete.
Still, this price competition, from the consumer's view, is a good thing. For example, when Superior Air Parts introduced a number of PMA'd Lycoming parts, Lycoming itself cut prices on those parts and stepped up production to keep the supply lines filled; previously, the parts, such as main bearings, were occasionally just not available. Parts produced on a PMA are myriad, ranging from fairings to major engine components to overhaul kits. Name a part on an airplane that is subject to common wear (like pistons and valves and landing gear components, unlike wings and ashtrays), and there's probably a PMA'd part available.
Price is a major factor in the success of the PMA program. For example, a new set of wheelpants for your late-model 172 will run you more than $1,400 from Cessna. (To the company's credit, the parts are still available.) But you can buy aftermarket, PMA'd wheelpants for half the cost from a number of suppliers. That's incentive.
There are also instances where the cost differential is not so great. One major engine overhauler told us that, because of his title as distributor for the OEM, the price difference between, say, factory valve guides and PMA- supplier guides was nil. In this case, he would prefer to use the OEM's parts. Besides price, this overhauler points out that there are some gray areas with regard to predicted TBOs on engines with aftermarket parts in them. When the manufacturer sets TBO (which, as you probably know, is nothing more than an educated guess at the engine's longevity), it is predicated upon the engine having all original parts. Throw in major components from outside suppliers, and the OEMs become reluctant to say whether the original TBO stands. All of which is not a huge concern for Part 91 operators, but for Part 135 and 121 operators, who have to replace or overhaul engines at the factory-determined TBO (or receive FAA-sanctioned TBO extensions), this can become a sticky issue.
Regardless of the part, any company with a PMA is required to mark its products "FAA-PMA" and provide part numbers and serial numbers on the part itself. If this is not feasible, say, because the part is too small to countenance so many numbers, the information can be provided on tags and/or other documentation provided with the part. So if you think you're buying a PMA'd part, check the paperwork carefully. Another tip from the industry insiders: Go with established manufacturers and distributors, and ask around about the reputation of said makers. Usually a company can get away with producing substandard parts for only a short time. Eventually, failures catch up with these operators, and word gets out. Also, make sure to ask your mechanic if he's intending to use PMA parts or originals. Because of brand affiliation, some shops are unwilling to use PMA parts unless the owner forces the issue, while others will use PMA pieces first and factory items last. Find out which of these types you're dealing with.
No discussion of parts makers would be complete without talking about bogus parts. Industry experts agree that bogus parts — i.e., those that look and feel like the original but are not the same structurally or in performance — are far more prevalent at the high end, for airliners and business jets. This is a simple matter of economics; the heavies have many life-limited, complex, and expensive parts. Forgeries of these parts can net the unscrupulous businessman tremendous profits. So far, it looks like the relatively low cost of general aviation parts has shoved the majority of bogus business up-market.
The bogus business is but a sliver of the GA parts situation, and to help grease the skids for future PMAs, AOPA has been working with the FAA to help streamline the standards. Though the changes are in the early development stages, AOPA officials are hopeful that simplified procedures will entice companies capable of building quality parts to join the existing PMA vendors (and those now in business could more economically expand their lines) and help ensure that a supply of replacement parts will be available in the coming decades. A good thing that would be, too, because we will need those parts.
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