JamesNoBrakes

Higher compression engines do not need high octane...anymore. Look at GMs direct injection 3.6. They are making 300hp and more without using high octane fuel. 326hp and 87 octane. There are more examples. The point is that automotive technology has continued to evolve relatively, and airplane engine technology stopped..way back in the beginning of the century.

What you say used to be true, until automotive timing and control got good enough. Turbocharged engines will probably always need some higher octane, but there was a multitude of reasons that lycoming listed why you can't just go and put 91 octane in a lycoming and run it. The real dissapointing part IMO is that they have not been designing to overcome this the entire time, rather they want the fuel designed for their engine.

What I'm proposing mostly is that the engine manufacturers stop producing these archaic designs and put some money into designing something somewhat modern that you can use 87, 89 or 91 octane pump gas in. Not that you can go and put 94 octane in it and get "ok performance", but that the engine is designed to run on those lower octanes from the get-go. For all those "old engines" out there, I think modifications (ignition systems rather than lawnmower magnetos) and fuel system upgrades are realistic solutions. It just seems like "designing the fuel for the engine" is always going to be a losing battle, there won't be but a few refiners making it, it will be very expensive due to the scale of production, and so on. I realize that to some extent this might have to happen for a few of the warbirds so they can perform at shows, but otherwise I just don't see any realistic to 100LL.

TonyWilliams

I had to look up that General Motors engine:

The LLT engine has a compression ratio of 11.4:1, and has been certified by the SAE to produce 302 horsepower (225 kW) at 6300 rpm and 272 lb·ft (369 N·m) of torque at 5200 rpm on regular unleaded (87 octane) gasoline.

Yes, that truly is a high compression engine, although I've had 12 and 13:1 engines on my motorcycles for a couple decades. With a carburetor!

Anyway, news flash; Lycoming isn't going to leave their bread and butter of grossly overpriced engines that you HAVE TO BUY if you have an airplane with one, since that's what it's certified for, and the cost to develop something new cannot be spread out over the relatively small fleets.

I been at Oshkosh many times to see the latest engine developments, and while there are many in the experimental machines, certified machines are a different breed. I've seen the Toyota (V-8 certified in the Malibu and Navajo) attempts, Honda (with Continental), and other big name players who know HOW to make an engine. None are available in the market for many, many good reasons (that aren't technical).

So, perhaps a new plane with a new engine is possible, but I sure hope it doesn't burn petrol !!! The best one I've seen that may have a chance is:

DeltaHawk Diesel Engines

Grumble

When an automobile engine can run at 75-90% for several thousand hours efficiently, without fail.... I'll put one in my airplane. Oh and it cant weigh more than the IO-360 I have in there now. The homebuilt crowd has been having this argument for decades and attempt after attempt has been made, with no real success for a reason. It dosent work. Only recently has electronic ignition and adjustable timing started to make it's way into the scene reliably. Mazda rotary engines are probably the closest thing to an answer, but no one has been able to crack the code on a reliable reduction drive unit. And running mogas above 8.5:1 is just fine as long as you run very very rich. Start leaning and your detonation margin is almost nil. Never mind the ethanol debacle.

If there is an answer, it's diesel. Someday.

Cubdriver

Lycoming and Continental are working on newer technologies to allow the new engines to run on any fuel, but the problem remains they are going to sell 4 of them, and while monopoly makes them drag feet somewhat the real issue is the small numbers of production- no matter what engine they produce. I do not see either company as a callous bullies with a strangle hold on piston aviation, more like a hobby industry that has a zero R&D budget. That plus the steep cost of certification testing for all airplane powerplants leads to the archaic state we have now. In addition to those blocks the other one is the incredible lifespan of the typical piston airplane. Where else can you find engines sitting around that are older than you are. Those engines have to be fueled, and they cannot realistically be retired as long as they run safely on 100 octane. It's going to take a drop in non-leaded replacement gasoline, plus a metric ton of years for all those high octane engines to be out of the picture.

JamesNoBrakes

I know lycoming isn't going to do it on their own, it's going to take something like the deltahawk being successful, and then lycoming/continental will try to "catch up" with a modern design, but the real question is if they'll fall flat on their face or pay for their lack of foresight.

That engine BTW makes 323hp in the 2012 camaro now, as it's been updated a little from the original spec that showed up in the CTS, impressive, but I had to go for the V8 version Yes, the V8 engine is 200lbs heavier than a IO-360, but it's making more than twice the power of one, and they are being used in light aircraft. There are others in the same catagory, and I think the basic principle is that automotive technology has advanced, and has been designed around the available fuel, rather than the other way around.

I think the only real constant in business is change, and that it's key to any successful company. The minute you start complaining about competitor A being able to do something for less, offer a cheaper or more popular product, you are falling into the rut of not being competative and failing to innovate. The idea of being able to make a wiget on a production line unchanged with the same machines and people will never work. This is my main gripe with "made in america" crusaders, because competition is necessary and it's when businesses do not evolve that they die. They need to invest in new processes, equipment, people, designs, new markets, new products, and so on. If you "sit on your heels", someone is going to smoke you. If lycoming and continental do not innovate and bring about the necessary change, they deserve all that is comming to them, and to die out. It's when the government steps in and props-up failing business and bad business models that the entire industry get dragged down and everyone suffers (see Airline Industry ).

I'm planning on building an RV-7...and diesel would probably be my first choice, there are some other decent alternatives too. It's getting there...

threeighteen

I'm after an RV10 with a deltahawk. winning strategy imho.

Cubdriver

Pain at the Pump-What the transition from 100LL avgas to unleaded aviation fuel could mean for you.

(Flying, S. Pope, 6/28/2012) Dissecting the just-released final report submitted by the FAA’s Unleaded Avgas Transition Aviation Rulemaking Committee (UAT ARC), here’s what you need to know about the future of 100LL avgas:

• There’s no real financial motive for any of the major fuel suppliers to create an alternative to 100LL aviation gasoline because the market is so small.
• No approved alternatives to 100LL currently exist, and coming up with one that can replace leaded avgas without requiring changes to aircraft systems might be impractical.
• The EPA doesn’t really care about these last two points, and is insisting that leaded aviation fuel be banished from production.
• The FAA’s experts think it will take 11 years, or maybe longer, to make the transition to an alternative fuel. As a result, the agency is launching a government-industry initiative called PAFI (Piston Aviation Fuel Initiative) to figure it all out.
• Nobody knows what an alternative fuel will cost at the pump – even more worrying, there is a risk that 100LL could become an extremely scarce fuel before the transition to an alternative is completed.

Reading between the lines of the UAT ARC’s report, I see few reasons why an acceptable alternative to 100LL avgas can’t be identified and approved. The key is timing. Some small companies have already come up with innovative solutions, with the major barrier preventing one or more of these fuels from entering mainstream production being the FAA’s own unwillingness to test and certify them. Of course, with the creation of the PAFI, that process can begin...

chrisreedrules

What about a bigger version of the rotax like they use in the Tecnam twins and a few others? They have pretty awesome performance and use MOGAS.

hindsight2020

You can run ethanol-laden mogas on lycos and contis too, the obstacles are not science based, it's all FAA red tape. The concern about ethanol eating away at materials just shows the GA fleet needs to get with the program. That is why I can't wait to go experimental, where none of the old wives tales of ethanol-blended mogas matter one iota. Then I can legally haul the stuff from the pump down the street to my airplane with automotive parts from the alternator on down to the brake lines and the fuel lines. Just don't fuel your airplane up and not fly it for 6 months. Your car wouldn't start either under the same circumstances...Screw 100LL.

I know I know, 10% of the GA market drives the demand for the other 90%, because that 10% of the fleet burns 90% of the gas. To that I say, let them have at it and release the rest of the fleet from the grips of 100LL by offering street mogas at the airport. Problem solved.

These spam cans are all going to the scrap yards when the boomers start losing their medicals en masse anyways. The economics of 8GPH per 100 knots and $20,000 1930s rebuilt tractor engines is economically outmoded for the current times.

Cubdriver

Nice of you to stop in, Hindsight.
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"Game changer" now that's an original phrase. The new diesel Skylane will work with biofuel Jet-A in due course of time. It's nice they are selling them now so the few that sell depreciate by time the cost per gallon of "bio-A" becomes decent in 2020 or 30. I still can't believe a 182 runs half million bucks though. Maybe it mixes martinis.

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Cessna unveils "Turbo NXT" Skylane

(AOPA ePilot, 7/23/12, S, Brown) A Cessna 182 powered by a 230-horsepower Jet-A-burning piston engine will be available in the second quarter of 2013, Cessna Aircraft announced July 23. The thinly masked Turbo182 NXT on display at the Cessna exhibit at EAA AirVenture drew widespread attention even before the official start of the show and unveiling. Cessna’s Jeff Umscheid said the aircraft is a response to customer demand. “This is what the market has been begging for,” he said, calling the aircraft a game changer. Powered by a turbocharged, direct-drive SMA SR305-230E-C1 engine, the Turbo 182 NXT will burn 11 gph at a max cruise speed of 155 knots, Umscheid said, granting owners a lower fuel burn and increased range from avgas counterparts...