GA Engine Summit 2017

Dec 1, 2017

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Industry and the FAA meet to discuss GA piston engine issues

In mid-September 2017, I was invited to participate in a two-day “GA Engine Summit” meeting in Burlington, Massachusetts—about 30 minutes’ drive northwest of Boston. This meeting was a long-awaited sequel to the first GA Engine Summit that took place in December 2015, which I also attended.

This year’s summit was attended by a veritable Who’s Who of piston GA. It was hosted by the FAA’s Aircraft Certification Service, and attended by representatives from across the piston GA industry. Attendees included numerous representatives of the FAA’s Engine and Propeller Standards Branch—formerly known as the Engine and Propeller Directorate—and other FAA branches involved with piston GA. Aircraft owners and pilots were represented at the meeting by AOPA’s David Oord, EAA’s Doug Macnair, HAI’s Zac Noble, COPA’s Roger Whittier, and CPA’s Paul New. Also attending were representatives from Continental Motors, Lycoming, Pratt & Whitney, Hartzell, Superior Air Parts, RAM Aircraft, DeltaHawk, Electroair, and the NTSB.

FAA Realignment

There was much discussion of the FAA’s sweeping reorganization—they called it “realignment”—that took effect last July. Both the Aircraft Certification Service (AIR) and the Flight Standards Service (AFS) had their org charts massively redesigned. This left many of us in industry wondering who was responsible for what under the new scheme, and how we should “do business” with the FAA going forward.

The new org chart for Aircraft Certification focuses on functions rather than hardware. The FAA’s traditional hardware-specific directorates—Small Airplane Directorate, Rotorcraft Directorate, Engine and Propeller Directorate, etc.—no longer exist. Instead, AIR now has functional divisions with somewhat inscrutable names like Policy & Innovation Division (“P&I”), Compliance & Airworthiness Division (“C&A”), System Oversight Division, and Enterprise Operations Division.

In Flight Standards, the FAA’s traditional structure of nine regions—New England, Eastern, Southern, Great Lakes, Central, Southwest, Northwest Mountain, Western Pacific, and Alaska—has gone away. There are still 78 Flight Standards District Offices (FSDOs), but they now report directly to FAA headquarters. There is still some confusion as to whether they’ll continue to be known as “district” offices—they might be renamed Flight Standards Field Offices (FSFOs?) at some point.

The good news for most of us is that while the FAA org charts and job titles have changed, most of our familiar points-of-contact in the agency will remain as our points of contact. The FAA seems to be making a serious effort to ensure that their massive internal reorganization will be as transparent as possible to its “customers.”

Electric Propulsion

Gary Horan of P&I gave us a fascinating briefing on electric propulsion from the FAA’s point of view. Gary indicated that both pure electric propulsion and hybrid electric propulsion are now becoming viable for short-range small manned aircraft. Of course, electric propulsion is already the dominant choice for small UAS (drones).

Gary is right in the middle of all this, and he said it’s happening very fast and feels like a revolution. The FAA sees small and novel electrically-propelled aircraft as becoming big players before the end of the decade. Following shortly thereafter, in the early 2020s, the FAA expects the introduction of hybrid electric propulsion in aircraft weighing up to 19,000 pounds. (Hybrid propulsion systems combine a conventional reciprocating or turbine engine with electric motors and batteries, much in the way hybrid automobiles do.) 

Gary indicated that it is clear from recent activity in which various industry applicants have been approaching the FAA for guidance on how to approach certification that electric propulsion is at the threshold of becoming a major player in the world of certificated aircraft. Driving this revolution is the development of improved battery chemistries and advances in electric motor technology.

The FAA’s goal is to facilitate the development of industry-based consensus standard for approval of electric and hybrid/electric propulsion systems, working through ASTM committee F39.05. This committee currently consists of 16 people, of whom five are from the FAA. Clearly the FAA is taking a proactive role in helping to guide this process. The first goal of the committee is to develop a consensus standard for a simple base electric motor system and means for compliance for small GA aircraft, something that is well along and should be completed very soon. Next, the consensus standard will be extended to cover hybrid/electric systems for Part 23 aircraft. Finally, it will be extended to commuter and Part 25 (air carrier) aircraft.

Alternative Fuels

Peter White, manager of the FAA’s Alternative Fuels Program, gave us an update on the Piston Aviation Fuel Initiative (PAFI)—the government/industry partnership to find a new unleaded aviation fuel that can be readily available across the GA fleet. The current 100LL avgas is considered “at risk” from EPA regulation, pressure from state and local governments, lawsuits from environmental groups, and from the fact that there is only one remaining supplier of tetraethyl lead worldwide. It’s not clear precisely when 100LL is going away. It appears safe for the next few years, but the handwriting is on the wall. About 167,000 GA aircraft depend on 100LL. 

In June 2013 the FAA requested that fuel producers submit their replacement fuel proposals to the FAA for evaluation.  By July 2014, the agency received 17 formulations from six companies and assessed candidate fuels in terms of their impact on the existing fleet, the production and distribution infrastructure, the impact on the environment, toxicology, and the cost of aircraft operations.  In September 2014, the FAA accepted four fuel formulations into the PAFI Phase 1 test program. 

Phase 1 testing took place at the FAA’s William J. Hughes Technical Center in Atlantic City, using six test rigs to test cold and hot fuel performance and compatibility with various common fuel system materials. Limited engine testing was also performed, evaluating power, performance, anti-detonation properties, and engine startability. Each candidate fuel was also evaluated for cost, producibility, storage stability, and environmental risk. By early 2016, Phase 1 testing had been completed and two candidate fuels were selected for Phase 2 testing: Shell UL100 and Swift UL102. 

Phase 2 testing of these fuels is now well underway, and scheduled to be completed in early 2018. Phase 2 includes both engine testing and aircraft testing. The engine tests involve performance testing of 20 engines of 15 different models, ranging from carbureted four-cylinder engines to turbocharged fuel-injected six-cylinder engines, plus some radials. Six of the engines have been subjected to detonation testing with each UL fuel and with mixtures of these fuels with 100LL (to evaluate phased deployment). Four of the engines went through 400-hour block tests using each UL fuel, for a total of 3,200 hours. The aircraft tests involve 10 aircraft models ranging from two-place light trainers to high-performance twins and helicopters.

Getting these unleaded fuels approved presents a unique regulatory challenge. That’s because the FAA doesn’t certify fuels; it certifies engines and aircraft to operate on specified fuels. But in this case, getting the UL fuels approved on a model-by-model basis for each engine and aircraft is clearly impractical. To get these new fuels approved on a fleet-wide basis, the FAA will require new statutory authorization. The FAA and industry is presently working with Congress to achieve this. Stay tuned.

Power-Loss Accidents

James Gray, an aeronautical engineer in the FAA Engine and Propeller Standards Branch, updated us on his study of more than 700 GA power-loss accidents that occurred during 2000–2014. There have been 200–300 such accidents every year, and roughly one in five have been fatal (about 50 per year). The number of non-fatal power-loss accidents has been slowly declining but the fatal ones have been flat, causing the percentage of fatal accidents to increase in recent years. 

As longtime owner of a Cessna 310, I was shocked to learn that the fatal accident rate for piston twins is more than twice the rate for piston singles. Another shock: The rate of power-loss accidents for experimentals is six times that of certificated airplanes—but a lot of those accidents have occurred during the initial flight test period, and the experimental community is working hard to address that problem.

The study shows that most power-loss accidents are caused by fuel problems. During the study period, 128 accidents were due to fuel starvation, 93 due to fuel exhaustion, and 43 due to fuel contamination. Another 31 were caused by carburetor problems, mostly carb icing. True mechanical problems were rare: cylinders (23), connecting rods (16), magneto (16), and fuel pumps (11) topped the list.

While three-quarters of power-loss accidents were caused by pilot misdeeds, maintenance errors also played a non-trivial role. These were classified in the study as overhaul (57), assembly/installation (43), and repair (12). The number of assembly/installation-caused accidents has been decreasing, but the number of overhaul-caused accidents has not. (Think about that when you’re deciding whether to go past TBO.)

ADs and AMOCs

Much time was spent on a subject near and dear to every aircraft owner’s heart: Airworthiness Directives. Christopher Richards, the aeronautical engineer in the FAA Engine and Propeller Standards Branch who is responsible for reciprocating engine projects, led these discussions.

Chris explained that AIR is responsible for Continued Operational Safety (COS). Their COS process consists of gathering data on potential unsafe conditions, performing a numerical risk analysis to assess the frequency and severity of the problem, collect candidate corrective actions, convene a formal Corrective Action Review Board (CARB) to decide what corrective action is appropriate, then draft the selected corrective action (AD, SAIB, etc.). In the case of an AD, they then issue an NPRM and address public comments, then issue a final rule.

This process has worked well for air carriers, but less well for GA. In the world of GA, event reporting is far less complete and accurate, making numerical risk analysis more difficult. GA operators are much more cost-sensitive, so the risk-vs-cost evaluation can be challenging. The FAA has historically had good communications with the aircraft and engine manufacturers, but less so with the people most affected: aircraft owners and operators. Unlike the airlines, few GA operators have engineering staffs or individualized maintenance programs, so most of us are reliant on recommendations from the aircraft and engine manufacturers (whose best interests are often very different from ours).

In order to help the FAA gather needed COS data for GA aircraft, and to help give GA owners/operators have a voice in the COS process, in 2001 we worked with the Small Airplane Directorate to create a new Airworthiness Concern Sheet (ACS) process. The ACS was designed to provide an early heads-up to AOPA, EAA, and relevant GA type associations whenever the FAA identified a potential unsafe condition. The ACS solicited event data from these alphabet groups, and gave them an opportunity to weigh in on the FAA’s concerns before formal rulemaking action kicked in. Originally, the ACS process was limited to the Small Airplane Directorate, but in 2015 the Engine and Propeller Directorate also agreed to use the ACS process when it was considering an AD that would affect GA.

In the past year, the ACS process was extremely helpful in allowing GA to weigh in on a threatened AD on Continental 520/550 camshaft gears that would have been extremely costly to tens of thousands of GA owners. It facilitated discussions between owner representatives, Continental Motors, and the FAA’s Atlanta Aircraft Certification Office that ultimately persuaded the FAA not to issue an AD and persuaded Continental to downgrade their mandatory service bulletin to non-mandatory. Unfortunately, it was unsuccessful in influencing the recent AD against Lycoming connecting rod bushings because the FAA decided not to issue an ACS and denied GA owner representatives any meaningful input into the COS process. At the meeting, several of us were quite vocal in expressing our extreme displeasure at how the Lycoming AD was handled, and asked that the FAA try not to let this kind of thing happen in the future.

We also discussed AMOCs: Alternative Means of Compliance with ADs. If an operator doesn’t like the corrective action mandated by an AD and thinks there’s a better way to address the unsafe condition, the operator can proposed an AMOC to the FAA, and the FAA will approve it if the operator can show that the proposed AMOC achieves a level of safety acceptable to the FAA. The airlines use this all the time, but GA doesn’t use it much (mostly because few GA operators have the engineering capability to create an acceptable AMOC proposal). At the 2015 Engine Summit, the FAA urged the various GA alphabet groups who attended to make better use of the AMOC mechanism.

In 2016, the FAA issued a draconian AD against ECi cylinders on Continental engines. AOPA in partnership with several affected type associations prepared a proposed AMOC to allow the condemned ECi cylinders to remain in service to TBO under certain controlled conditions. The FAA rejected our AMOC proposal on the grounds that we had not provided sufficient data to prove that it would achieve an acceptable level of safety. This subject was discussed at length at the meeting. We complained that the FAA had acted unreasonably by requiring us to “prove the unprovable.” The FAA said that their intent was not to shoot down our AMOC but to invite further discussions. Of course, by now the subject is moot because virtually all of the affected ECi cylinders have been already removed from service. Representatives of the owners and the FAA agreed to try to do better next time.

All in all, it was a highly productive meeting. Everyone agreed we should try to have such meetings annually, and the next one was tentatively set for September 2018.

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