Whither Avgas

[Justiciar]

Pilot reports this month that ExxonMobil have closed avgas production at a plant in Scicily.

This seems to raise the concern of the future of avgas production, certainly in Europe and perhaps world wide. Whilst we in Europe cope with increasing costs and tax, making flying ever less affordable, do we face a much more serious threat, that of having aircraft and nothing to fuel them with?

Despite modern technologies and the emerging market in Diesel aircraft, the vast majority of the GA fleet is powered by avgas. Yet, to the manufacturers of avgas, it is a very small part of their operation. How far are we away from the day when avgas production ceases in Europe?

What does the future hold? Even those of us with aircraft designed to operate on mogas are under threat. The inclusion of 5% biofuel may end the use of mogas in PFA type aircraft and force them to avgas!

What do the panel think? Hope for light diesel engines? Take up gliding?

[IO540]

There are tens of thousands avgas powered planes in the world *outside* the USA, and I don't see the stuff drying up as quickly as is threatened in the press.

It will go one day, I am sure, but so will all good things :)

One day, Thielert (or whoever) will find a way to make their diesel engines make TBO without falling apart, and that will be good news.

[sternone]

Thielert (or whoever) will find a way to make their diesel engines make TBO without falling apart, and that will be good news.

Why does it takes so long to make a reliable diesel engine ?

Also, does Continental and Lycoming have any plans to make a diesel engine ?? They must if they wan't to stay alive ?

[JUST-local]

Take a look on the web, Lyc and Detroit diesel made an aero oil burner nearly ten years ago! Don't think it was ever certified or went beyond the project stage, if you find the article you will see it looks very like a turbocharged 0-320, we can only dream! :zzz:

The certification & production costs against customer base were probably a no go! :ugh:

I am certainly looking forward to when they decide to dust that one off and get the ball rolling. :ok:

JL.......

[sternone]

Is there any car engine that fits the bill for an aircraft ?? Back to my porsches.. they tried that in the mooney but they had loads of problems i read...

[Saab Dastard]

I'd be prepared to donate my Porsche 928 engine when the body / transmission / suspension gets beyond economic repair!

5 litre v8, normally aspirated, delivers about 320hp. Supercharged versions of this engine can reach 600hp!

Only the small obstacle of certification to overcome! ;)

SD

[DBo]

Continental appointed Mark Wilksch (one of the men behnd the Wilksch diesel engine) as director of new engine development in June - that might suggest that Continental are keen to develop a diesel...

Report here http://dieselair.com/2007/07/cessna-announces-collaboration-with.html (http://http://dieselair.com/2007/07/cessna-announces-collaboration-with.html)

Dave

[sternone]

Wauw, problem solved i guess... so we will just swap our avgas engines with the diesel ones in the same airframes...


News of July 01, 2007

Diesel guru Mark Wilksch joins Continental

After a split with the UK company that continues to develop the WAM-120 diesel aero engine, and a brief sojourn in his native Australia, designer Mark Wilksch has reappeared on the general aviation scene with his appointment as director of new engine development at Teledyne Continental Motors (TCM). Although it is associated with 'traditional' aero engines, TCM was working on its own aircraft diesel engine some years ago. It's easy to speculate that Wilksch, whose WAM-120 was very much a 'clean sheet of paper' design, may have been brought in to set some kind of diesel programme back in motion at the US giant, which is based in Mobile, Alabama. (Flyer.co.uk, 5/31/07)
DieselAir comment: We can assume that Continental is initiating a new diesel design and have no doubt that Mark Wilksch can help them. It will be a long term project. Meanwhile it confirms the coming of the aero diesel age

[rotorfossil]

Trouble with diesel engines is that if the threatened change in taxation regime for aviation use of Jet A1 fuel happens, almost all the benefit of going diesel is lost.

[Humaround]

It seems unlikely that the issues involved in coaxing Lycosaurs to run on Mogas are insurmountable. Many already do (Superior clones) although the increasing amounts of alcohol being used in mogas is another spanner in the works.

I fully expect one day to hear that Lycomings are running sweetly on pure ethanol. I leave the trivial engineering details to others.

:hmm:

[Justiciar]

I am not sure that tax is such a problem, until governments decide to tax all air travel out of existance. The problem is one of availability. I don't imagine that the engine manufacturers have much clout with the petroleum producers and if they decide there is no money in avgas it could go very quickly. What will those owners of aircraft do who can't afford to retro-fit a diesel?

[Zulu Alpha]

What are the problems with alcohol in road fuel that prevent it being used in aircraft. I know there are issues with seals, but surely these are easily changed.

Is there something more fundamental. I would have thought that if cars can use alcohol then aircraft could as long as they don't go above a certain height where the alcohol vapourises.


ZA

[IO540]

Reportedly the problem with mogas is something to do with its vapour pressure and resulting problems with altitude.

[soay]

Alcohol is also hygroscopic, so you can end up with water in your fuel that doesn't show up when you take a sample. That will affect both its performance and its freezing point.

[Justiciar]

There is also the issue of the energy content of fuel with alcohol as opposed to that without.

[TheOddOne]

It's not just the engine falling apart well before TBO that is the problem. We can't operate the diesel powered PA28 at shorter runway lengths for training as it doesn't develop enough power during the take-off roll to give enough margin for students.

I believe that the engine weighs more than the equivalent-power aircooled AVGAS engine, the fuel weighs more and you need more of it. Thus the useful load is less, unless you re-certificate at a higher weight.

The diesel engine I understand comes into its own in the cruise, once you've got there. Not much use for training, really, I'd have thought.

I understand that AVGAS is a useful fraction from most refining processes and so the oil companies are willing to continue to produce the basic product. The problems come from the tighter quality control etc that are rightly demanded and the relatively tiny market.

TheOddOne

[TheOddOne]

I guess that Cessna have a feel for the future of AVGAS - they've now chosen a Continental AVGAS engine for their C152 replacement. Presumably we'll see the UK training fleet made up of these a/c in 10 years time, when the schools in Florida have flogged 10,000 hours each out of them and someone imports them into the UK. (I think that's how most of the C152's got here, anyway!)

TheOddOne

[soay]

Just when you thought it was safe to forget about this thread ...

I see that the US Environmental Protection Agency have asked for information and comments from all interested parties on the issues raised by a Friends of the Earth petition (http://www.epa.gov/otaq/regs/nonroad/aviation/foe-20060929.pdf) to ban lead emissions from general aviation aircraft. See the EPA's Request for Comments document here (http://www.epa.gov/otaq/regs/nonroad/aviation/frn-20071109.pdf).

I suppose it will take drastic action like that to force Lycoming and TCM to adapt their engines to other fuels, or even nastier additives.

[GOLF_BRAVO_ZULU]

Perhaps if they had been really clever, the huggies could have pushed for all piston engined aircraft to be fitted with catalytic converters.

It has always gripped mine that we were pushed into unleaded at a time when we are supposed to be squeezing every last ounce of energy out of every barrel of Crude. A chemist friend of mine once told me that some of the combustion products from ULGAS burned in an average car would be banned if it was an industrial process.

[tangovictor]

rotax engined aircraft use mogas, without any problems

[soay]

rotax engined aircraft use mogas, without any problems
What, even when the required 5% of biofuel is added? This (http://www.iaopa-eur.org/contentServlet/pid1000392.html) is what IAOPA have to say about that:
AOPA-Germany has won an exemption for avgas from laws due to come into force in January which require all German manufacturers of fuel to add Ethanol to their products. The exemption, however, does not cover mogas, and all GA aircraft using mogas will be affected.

Ethanol is a biofuel that is popular among environmentalists, and in some countries like Brazil it already forms 20 percent of car fuel. It has a lower energy content than pure gasoline, which makes it unsuitable for high-performance aircraft engines. It also has a more corrosive effect on certain engine components.

Dr Michael Erb, managing director of AOPA-Germany, says they managed to convince German authorities that adding ethanol to avgas would be a disastrous move, both economically and in terms of safety. However, exemptions are less likely for car fuel, and it is economically unfeasible to produce ethanol-free mogas purely for aviation use.

Dr Erb points out that the STCs for Lycoming engines designed to take mogas prescribe a maximum ethanol content of one per cent – any higher and the permit is invalid. Rotax engines in VLAs and ultralights will also not tolerate a higher concentration of ethanol.