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Because flying is cool
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In my last column, “How the search for unleaded avgas is like two elephants mating,” I talked about how those who work at refineries view avgas.
When the story ran online at the General Aviation News website, there were a number of useful comments, which I always appreciate.
One comment stood out to me. PeterH stated: “The technologies that allow our antique aircraft engines to burn unleaded gasoline, such as electronic ignition systems, direct gasoline injection systems, and water injection systems, are well known. They will simply have to be adopted by the industry and subsequently approved by our infamous regulators.”
This is a sentiment that I and many others have held for years. In the 1990s, Caesar Gonzalez from Cessna proposed a spec for 87UL avgas that was basically auto fuel. His theory was that if general aviation was to go forward — and maybe even grow in the future — then it would need to utilize the large pool of motor gasoline and not a specialize boutique fuel like avgas.
A lot of 80/87 engines have been run on autogas for many years. But to really advance its use, we need to advance engine technology, as PeterH suggested.
Unfortunately, the GA world is stuck in a Catch 22. We are using engines that use technology from the 1930s and 1940s, which meet FAA standards that were written to cover the technology for those engines. Those standards do not apply to 2022 technology engines.
What is needed is a reasonably priced spark ignition aircraft engine that could be used in trainers and GA aircraft.
One of the reasons that GA has not grown is that flying today’s aircraft scares the hell out of young people.
I know that all of us old people had to learn how to pre-heat the engine and other functions, but that is a very poor sales pitch to bring in new customers. If young people are afraid to drive a manual transmission car, what chance do we have to convince them to lean out the carburetor after takeoff when they do not have the foggiest idea of what a carburetor is or what it does.
If a small aircraft could be developed around a liquid-cooled modern technology engine, it would make flying something that young people could relate to and would feel comfortable doing.
They would just go out to the airport, do the preflight checks, get into the aircraft and start it up. No pre-heating on cold days or setting the mixture strength and hitting the primer. Just turn the key and taxi out. No mag checks or mixture strength adjustment or waiting for the engine to get to temperature. Just take off and enjoy the fun of flying. No leaning out or anything.
An added benefit would be that modern technology engines could use modern engine oils. This would eliminate pre-heating, cam and lifter rusting, and almost every other oil-related problem in today’s aircraft.
The need for an oil change every four months would be gone, while oil consumption of a quart every four to eight hours would be greatly reduced. With the lower oil consumption, the problem of pre-ignition would go away and fuel economy would be greatly improved. (The engines would also have knock sensors for additional protection.)
And the cost and maintenance advantages go on and on.
And then there is the very significant emission reductions that will no doubt become mandatory in the future. The engines, even without a catalytic converter, would have almost no CO or hydrocarbon emission, reduced NOX and CO2 emission, and so on and so on.
So, what would it take to drag the GA world into this century?
It would take a concerted effort by the FAA and the industry. Change is very scary, especially when the spectre of liability is ever present.
But public pressure on emissions and high fuel consumption limitation may force us to change whether we want to or not. The general public and regulators do not care that we are aviation. If the rest of the world can do it, so can GA.
Ben Visser is an aviation fuels and lubricants expert who spent 33 years with Shell Oil. He has been a private pilot since 1985.
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The problem is going to be money. You could get a modern engine past the FAA approval if you spent enough money but when you did the engine would be a $100,000+ engine so you could pay down the development cost in a reasonable amount of time given the very small GA market. When a car company develop a new engine they have more sales in the first month than GA has for all piston engine aircraft in 2 years. Young people today are already having financial problems as it is they are not going to be able to afford $500,000-$700,000 dollar aircraft even as a rental. We have a real catch 22 in that we can’t get modern engines without a larger market but we can’t get a large market without modern engines. What we need is a very rich person (like Elon Musk rich) that is willing to take a chance on spending large sums of money on a chance of expanding the market in the future. You can’t really do it by raising money from a lot of middle class stockholders because most of them are getting into retirement and are unwilling to risk money on something that won’t pay off in the next couple of years.
Well, traditional aviation engines vs. automobile engines are sort of like apples vs. oranges. Auto engines are almost always high-rpm, while aviation engines get a lot of power at lower rpms. So you’d need to lug around a gear reduction system to get that auto engine to turn the prop at an efficient (sub sonic) rpm. So, added weight, and associated failure points that mean added inspections.
Then, why would you carry around a cooling system (more weight) and all of it’s associated failure points when there is a weight free (almost trouble-free) cooling media right there in the clear blue sky?
The aviation engine manufactures are not sitting by idle either. FADAC systems are here now and will improve as time marches on.
Also, flight training has evolved too. Cranking out commercial transport pilots is the new world. Recreational flying is increasingly a smaller niche market.
This is a worthwhile discussion and I’m glad you brought it up, and happy to add my 2 cents.
47 years AMT/IA
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