Top Letters And Comments, May 21, 2021


FAA Wants To Add Cardinals To Cessna Spar AD

The proposed AD covers all Cardinals ever built. Though the 177 carry-through spar is similar to the 210 spar design, the 210 is a much heavier aircraft with greater potential for stress fatigue. As far as I have been able to glean from the NTSB fatal accident records, there has never been a failure, in any model, of the 177 carry-through spar in service, an interval which now spans seven decades. While the proposed eddy-current inspection requirement may be appropriate to gather data about prevalence of significant spar corrosion in the 177 fleet, it will be difficult to perform that on the most of the 210 and all of the 177 fleets in the next year.

One particularly counter-productive clause in the proposed AD would prohibit ferry permits if the carry-through spar inspection finds problems requiring remediation or replacement. This is potentially extremely burdensome and threatening for most owners, since the required level of eddy-current inspection is not available in most airports. Owners and operators should have the option of flying their planes to locations where the required eddy-current expertise and equipment is available, without fearing that the plane will be stranded away from home base indefinitely if a problem that requires remediation, replacement, or further consultation is found. In the worst case, replacement could entail indefinite downtime while Cessna restarts production of 177 spars or while other AMOCs are developed.

Cardinal owners shouldn’t have to truck their planes back to their home base if the inspection is unsatisfactory, instead of having the option of a one-time ferry permit. This absolute prohibition of ferry permits is wildly incommensurate with the sterling service record and small potential hazard, and will strongly discourage prompt compliance with the proposed AD’s eddy-current inspection requirement. Hopefully this counter-productive language will be removed after the FAA reviews public comments.

Craig Steele

Why New Aircraft Engine Ideas Rarely Succeed

Good presentation, Paul. One thing I want to thank you for is dispelling the myth that automobile engines will never work in aircraft because they can’t handle the 70% duty cycle. Maybe that was true of the old large block V-8’s of the past, but the smaller aluminum block turbo fours and sixes of today’s cars are different. They naturally operate at higher power levels anyway.

Piston engines, like turbines, are happiest when they run at a constant, relatively high output power setting. The fact that car engines tolerate the low power daily commute better than an airplane engine would has more to do with their unleaded fuel and water cooling than anything else. I see no reason why the 265 hp turbo four in my Honda couldn’t replace the 200 hp IO-360 in my Cardinal and do just fine. Yes, as you made very plain, it would have teething problems to be worked out, but the key would be more how well it was supported with warranty and maintenance than anything else.

However, in the end, the big question is why would Honda or anyone else bother to spend the time, money and engineering talent on something that would produce a paltry 2-300 sales a year? Probably our best hope for a “modern” aircraft engine is to retrofit electronic ignition and computer-controlled mixture settings on existing power plants. Lycoming is at least heading that direction by offering EI on factory engines to replace at least one magneto. Now if someone would just discover that magic lead-free replacement for 100LL, we might be making progress!

John Mc.

Poll: Do You Think GA Airplanes Need More Modern Engines?

  • I would love to fly a more modern reciprocating engine. Make it last 2000 hours, and not cost any more than current engines then that manufacturer will own the market. As far as I can tell that has not happened yet except for turbines which cost more than the airframe it is attached to! – Matt W.
  • We could certainly use more modern engines, but GA’s biggest problem is dealing with the legacy fleet. Getting a modern engine for new aircraft is one thing, but considering the small number of new plane sales these days, the economics are not really there. Finding a “better” engine to replace those in the legacy fleet would provide a much larger market, but regulatory hurdles and the ability to get the engines serviced make that a near-impossible task, as Redbird and others have discovered.
  • Yes, we should be able to have more modern engines. We should also be able to use more modern technologies in repairing our legacy engines – such as electronic magnetos, they’ve been in use reliably in experimentals for years!
  • Nothing wrong with the basic design. They are generally reliable and have good power to weight ratios and good specific fuel burns. Incremental improvements like the roller rockers and the more modern mags like Surefly are all that’s needed.
  • I love the fact that when the battery melts, the alternator fails, the fuses blow, and the wiring fries, the mags don’t care and the engine keeps running as I get the airplane to a mechanic. So, no, not more modern than that.
  • When we find an affordable option to 100LL, the vintage engines most of us fly behind will be much improved. New technology will make its way under the cowl but if it’s not affordable, it won’t be a viable alternative.
  • Not unless it offers a new quality of flying.
  • Yes, we’re flying antiques. New technology needs to have equivalent or better reliability.
  • There are plenty of “new technology” aircraft engines, however the economics of development and marketing will never justify the investment. DeltaHawk is a great example, 75K+ for a 200 hp engine vs $45K for a IO-390?
  • Government regulation greatly inhibits the introduction of more modern technologies.
  • No. The engine design is fine. The preventative maintenance and upkeep are the problem.
  • Add EFI and electronic ignition with ‘knock’ detection. We will then have “modern engines.”
  • Yes, they do (for fuel compatibility reasons if nothing else). Unfortunately the development (and if required, certification) costs make it mostly a losing proposition. I’m adapting a Lycoming with EFI for my homebuilt but that’s not practical for certified aircraft.
  • No, it is not NEEDED. But l will admit “updating” legacy aircraft engines is a good thing. The problem with updating or going to a new kind of engine is cost. GA costs are driving airplane ownership, and even obtaining a license, to being something “only the elite” can afford. The “an airplane in every garage” concept is no longer possible. I read about the new flying cars and laugh. Who can afford them other than the elite? Another pipe dream for GA.
  • We need modern electronic controls. The mechanical bits can stay as is.
  • There is room for both electric and modern liquid cooled internal combustion engines fueled with Jet A and 100LL. The airplanes and engine will, as currently, fit the intended mission. For electric to take over the storage device must at least provide the duration (range) of existing aircraft or exceed it to deliver the value. Electric motors and controls should be less expensive to manufacture than internal combustion engines.
  • Of course, but the darn thing has to work. Also has to be affordable. People say we fly antiques, well sure but the new tech has to outperform the old tech.
  • Yes, common rail diesels. They are the real future!
  • Get rid of carbs, mags.
  • No. We need them to be affordable!
  • I’m afraid reliability might suffer with too much tech. Economy and longevity are great but costs need to be kept down as well.
  • We need new tech, but needs to be cost competitive.
  • Only if they are piston engines that burn Jet-A/Diesel.
  • Yes…but the market volume just isn’t there to support it.
  • The old technology works and the upgrades and improvements over the years I’ve been in GA have been awesome.
  • What we need is engine we can afford.
  • Yes but the insurance, lawyers and FAA make this expensive and the certification process too long.
  • Old technology can be easily improved but prevented by product liability.
  • Seeking more modern powerplants has been one of the drivers of EAA.
  • Yes. Let FADEC take care of optimal engine handling.
  • Diesel.
  • Yes, but most of us can’t afford new airplanes to get them.
  • Go with turbofans (lots are on cruise missiles) or fuel cell.
  • Yes, now that automotive technology is advancing so fast, it is time.
  • Incremental improvement to “old” successful engines suits me just fine.
  • Need more modern engines? No. Should more modern engines be introduced? Yes. Choice requires more than one option. Multiple options demand a return on investment. That IS the fundamental of GA. Until that gets solved, we don’t NEED more modern engines.
  • How about something that doesn’t need lead in the fuel?
  • We need to fly with the engines we already have MORE OFTEN.
  • Need, NO. Find desirable, PERHAPS. GA has largely priced itself out of the market already, so it’s not surprising that new engine technology is slow to come in a declining market.
  • Yes, diesels. 100LL needs to go.
  • It depends on what your aviation aspirations are.
  • You guys are all dreaming. No electric motor is going to replace gas-powered, sorry.

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