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Airframe and Powerplant: New airplanes, new rulesAirframe and Powerplant: New airplanes, new rules

Light-sport maintenance in a whole new worldLight-sport maintenance in a whole new world

Unlike manufacturers of FAA-certified airplanes, Light Sport Airplane (LSA) manufacturers helped write the certification rules for their products. LSA airframe manufacturers are players in a diverse group that includes the FAA, members of the Light Aircraft Manufacturer’s Association (LAMA), and experienced users.

LSA lingo

Condition inspection—a yearly inspection for ELSAs and SLSAs. Must be performed by an A&P mechanic, someone with a repairman-maintenance rating, or the owner of an ELSA with a repairman-inspection rating for the airplane being inspected.

Experimental LSA—Three types of airplanes may qualify: an existing ultralight-like aircraft that does not meet Part 103; a new aircraft built from a kit that complies with the consensus standards; and a Special LSA that the owner has converted to the ELSA category for sport and recreational flying.

Letter of Authorization (LOA)—a letter issued by an airframe manufacturer approving a maintenance task, repair procedure or modification. All maintenance that is included in the manufacturer’s maintenance manual is classified as a minor repair. Any task that is not in the manufacturer’s manual is categorized as a major repair or alteration and requires a LOA.

Safety directive—A mandatory notice from the manufacturer of an LSA airplane that requires the owner to perform, or have performed, maintenance to maintain safety of flight.

Special LSA—an LSA that is delivered flyable from a manufacturer that has certified that it meets ASTM consensus standards. May be flown for hire. Must have 100-hour inspections and yearly condition inspections when flown for hire. Can be converted to ELSA category by owner.

Standard category airplane that meets LSA standards—an airplane that is certificated by the FAA in the standard category and does comply with the LSA standards. There are 131 specific aircraft models that qualify including Ercoupes, some Luscombes, most Taylorcrafts, many Pipers including the J-3, many Aeronca models and others. Preventive maintenance listed in FAR Part 43 Appendix A may be performed by the owner; however other maintenance must have A&P oversight or be performed by an A&P. These airplanes may be flown for hire.


Unlike manufacturers of FAA-certified airplanes, Light Sport Airplane (LSA) manufacturers helped write the certification rules for their products. LSA airframe manufacturers are players in a diverse group that includes the FAA, members of the Light Aircraft Manufacturer’s Association (LAMA), and experienced users. The FAA’s Sport Pilot rule requires that LSA manufacturers issue a statement of compliance that attests to the aircraft being built to the industry consensus standards, which then leads to the issuance of a special airworthiness certificate by a designated airworthiness inspector. The consensus standards that this group established also apply to how LSA maintenance is performed, and who is qualified to do it.

“The light sport airplane is an experiment. The FAA, LAMA, and industry leaders all agree on that point,” says Dan Johnson, an LSA advocate and chairman of LAMA. This experiment places all the responsibility for airworthiness, maintenance programs and procedures, and continued airworthiness in the airframe manufacturers’ hands.

At this point in the experiment, the requirements for maintenance can vary widely. Some manufacturers specify metric hardware; others use hardware that’s more familiar to A&Ps. LSA buyers should know that LSA maintenance rules vary from one manufacturer to the next. Because of this, prospective LSA buyers are advised to check the availability of trained maintenance providers in their area during their pre-purchase, due-diligence inspections.


Two sets of rules govern LSA maintenance. The same airplane can be certified under one or the other, or both, although not at the same time. 

“In SLSA maintenance the manufacturer is god,” says Kregg Victory of Victory Aviation at Reid-Hillview Airport in San Jose, California. Victory is citing the most important rule of SLSA maintenance—all SLSA maintenance must be accomplished in accordance with the airframe manufacturer’s service manual.

Bill Boege, an A&P technician who supervises the maintenance of more than 30 LSAs for Light Sport Airplanes West in Salinas, California, says that if an LSA manufacturer’s maintenance manual cites a specific name-brand tire, such as McCreary or Goodyear, as the approved tire on the airplane, that’s the only tire that can be installed. This requirement differs from the freedom that maintainers of certified-aircraft are accustomed to. Experienced A&Ps and certified aircraft owners are accustomed to rules where generic items such as tires, tubes, mixture control cables, that are built to an FAA-approved standard—in the case of tires a technical standard order (TSO)—are used interchangeably. These practices have no equivalent in the LSA world.  Deviations, modifications, and repair procedures that are not detailed in an airframe manufacturer’s manual are classified as major repairs or alterations. Only the airframe manufacturer may grant approval for a major repair or alteration by issuing a letter of authorization (LOA). Most LOAs are airplane serial-number specific.

Not only must the maintainer follow the manual, each task in each manual has a paragraph specifying who is approved to work on each particular task on the airplane. “The manufacturer has complete control over who does what to his airplane,” says Johnson. Johnson is often quoted on his Web site,, in regard to the LSA industry. The fact that there’s no wiggle room in the maintenance manual is one complication.

Varying standards

Pete Krotje (pronounced krooty) is the owner of US Jabiru of Shelbyville, Tennessee. Jabiru, an Australian company, produces two LSA airplanes. In addition to the airframes, Jabiru designed and now produces two air-cooled engines for the LSA market. Krotje foresees maintenance problems for this fledgling industry. More than 150 people have attended Jabiru maintenance programs in the last two years, but Krotje says, “a minority of attendees” intend to set up LSA maintenance shops. Krotje added, “I think light-sport maintenance is a pretty uneven field right now.”

“Jabiru uses only AN hardware,” says Krotje. (AN is Army-Navy industry standard part number.) This statement illuminates a potential headache for LSA owners and maintenance providers—airframe manufacturers can choose to control everything on the airplane right down to the nuts and bolts. If a manufacturer’s manual defines the hardware on its airplane by a company-generated part number instead of an industry-standard part number such as AN, Military Standard (MS), or Society of Automotive Engineers International (SAE), this can create a maintenance roadblock. In some cases maintainers are bound to go back to the manufacturer for every part.

Boege’s solution at LSA West is to purchase hardware in large lots and stock it in different-colored rolling parts carts such as green for Flight Design hardware, yellow for Evektor, and so on. The same manufacturers that have the power to control maintenance also have the power to make changes.

“One of the big plusses is how much simpler it is to get a manufacturer’s permission to make changes or modifications,” says Brian Carpenter of Rainbow Aviation in Corning, California. “We can send pictures of a problem or a request for a change to a manufacturer by e-mail or by fax. It’s not unusual to get a response back within hours.”

Some FARs do apply

Some existing FARs do apply to LSA maintenance.  FAR 43 is the regulation that governs maintenance, preventive maintenance, rebuilding, and alterations. Section 43.13, the performance standards paragraph, does apply. It defines what is expected of maintainers when it cites that, “each person performing maintenance…shall use the methods, techniques, and practices prescribed in the current manufacturer’s maintenance manual.”

It further says that the maintainer must use tools, equipment, and test apparatus necessary to complete the work in accordance with accepted industry practices. And that the work must be accomplished in such a manner, and with such materials, that the condition is at least equal to the original condition.Other FARs that apply are Part 65.107 subpart E (Repairman); Part 91.327 subpart D (Special Flight Operations); and Part 43.1 (Maintenance applicability).

If the buyer of an LSA has no intention of using his airplane for hire, he may certify it as an experimental light sport airplane (ELSA). Experimental airplane and experimental LSA maintenance is not addressed in the FARs, so ELSA owners are free to maintain and modify their airplanes as they wish.

A yearly condition inspection is required for both ELSAs and SLSAs. SLSAs that are flown for hire—and ultralight-like aircraft that were converted to ELSAs before January 31, 2008, and are used for flight training—are also required to undergo 100-hour inspections. The owner of an ELSA may perform the yearly condition inspection on his own ELSA if he or she has successfully completed a 16-hour repairman-inspection (LSRI) course, which is offered at various locations around the country. However, a repairman-inspector may not conduct condition inspections on ELSA aircraft owned by other individuals, even when the repairman’s and the other individual’s airplanes are identical.

The Sport Pilot rule was promulgated on September 5, 2005. At this time, almost all of the airplanes in the LSA fleet are still in warranty. But this new world has confused many an experienced technician.

New rules create new fools

“Our number-one problem is A&Ps and IAs [authorized inspectors] and you can quote me,” says Carol Carpenter of Rainbow Aviation in Corning, California, the only school in the United States with an FAA-approved repairman-maintenance (LSRM) school for the LSA market. “They’re a huge problem. They just don’t understand the rules.”

About 133 people from 38 states have completed the 120-hour course required for the repairman-maintenance rating, she said. Individuals with LSRM certificates may perform preventive and normal maintenance on both ELSA and SLSA aircraft and charge for their services. Others that may charge for these services include A&P technicians and FAA-approved repair stations.

An additional hurdle for the certificated LSRM and the A&P who wishes to conduct maintenance on LSAs is getting educated on service and maintenance practices on both the liquid-cooled Rotax engines and the air-cooled Jabiru engines. Schools are available and they are reasonably priced.

A visit to Rainbow Aviation

I flew into the Corning airport recently to take a look at Rainbow Aviation and meet the Carpenters. They were in the middle of teaching a three-week LSRM course. Six of the eight attendees were experienced pilots and maintenance professionals from the certified world. “About 33 percent of the LSRM course attendees are A&P mechanics,” says Carpenter.

In addition to running Rainbow Aviation, the Carpenters are also members of the consensus board for LSAs. This group meets by teleconference on a regular basis. This process makes it easy for the industry to identify and address shortcomings. This upgrading process has been applied to manuals. “The original continuing airworthiness standards for maintenance manuals were six pages long. We’ve expanded those standards to 24 pages,” said Carol Carpenter.

In spite of the glitches in LSA maintenance, the promise of a consensus-monitored marketplace is its ability to quickly adapt and upgrade the rules that govern the industry. The hoopla surrounding the LSA experiment will most likely subside as the industry matures. That, plus the inevitable winnowing of the number of manufacturers, should result in more uniform maintenance standards.

The LSA industry is gathering momentum. A few of the maintenance concerns have been touched on in this article. This new chapter in aviation will speed up during the next two years as SLSAs from mainstream manufacturers such as Cessna and Cirrus Design begin to appear on the nation’s airports. The future of SLSAs will depend on three things—viable airplanes that are fun and affordable, dependable manufacturer support, and trained, informed maintenance technicians.

If this experiment turns out to be successful, will a quick-reacting, industry-centered, consensus-created system become the preferred vehicle for certifying tomorrow’s newest airplanes?

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