Lead in aviation fuel isn't disappearing anytime soon.

[kevinsky18]

I?m getting a bit tired of the whole "when 100LL" disappears scare. This chicken little, "the sky is falling" syndrome needs a bit of check and balance.

Yes there is an environmental concern and yes people would like to see all leaded gas removed. However that?s not going to happen anytime soon in the aviation community.

First environmentalists are mostly focused on over all carbon emissions. 100LL is only a minor part of that when compared to all the gas driven vehicles out there. In other words we are very small blip on their radar.

Second, every gas piston airplane engine uses lead gas. Therefore in order to get rid of it there would have to be an official announcement with at least a ten year grace period.

Third, as most know lead is not just an octane boaster it is also a lubricant for these engines. Even if you have low compression pistons, if lead is removed no aircraft engine will be getting the lead lubrication that it needs. In other word everyone is in trouble not just the high compression engines.

Fourth there are lots of additives out there to boast octane so that?s the least of anyone?s worries if or when lead is removed from aviation fuel. Everyone?s biggest worry is going to be lubrication and this can?t be made up by adding another quart of oil that?s a different kind of lubrication all together.

Fifth and this is very important. If lead was removed from aviation engines every certified engine would become decertified, period! There is no way that Lycoming or Continental would continue to say our engines are going to make TBO. Their response would be plain in clear, ?We can no longer reliably predict the life and reliability of our engines, either discontinue use of the engine or fly at your own risk.? And there are far too many vested interests in certified engines to let that happen: From the engine makers themselves, to airplane manufactures that use these engines to the hundreds of thousands of owners both commercial and private that would no longer have a certified aircraft.

People will say but car engines run just fine without lead. Yes today car engines are designed to run without lead. But older engines suffered consequences when the conversion was made years ago.

For a good example look at NASCAR they are having troubles converting from leaded race gas to unleaded and they are blowing engines in record numbers. But of all the troubles they are having getting the gas to the proper high octane they need is not one of them, it?s lubrication.

Will lead one day be removed from aviation fuel? Yes one day it will happen but when that day comes all leaded gas engines are in trouble not just high compression engines. If you want to be future safe then you need to be looking at alternatives; car engine conversions, turbines or certified aviation diesels.

I believe the aviation diesel engines will be the ones left standing when lead is removed. As it?s over all a better more efficient principle, runs on jet fuel and the cost of developing a diesel engine would be the same as developing an unleaded gas powered engine. And as far as I know there are a number of certified diesel engines flying already and I?m not too sure if there is even one certified unleaded gas engine even on the design table.

So for now I?m going to run high compression and not even think about the ?what ifs? of lead being removed. I?m betting that my engine will be well beyond TBO by the time that happens and I?ll have ordered a diesel retrofit.

[Low Pass]

I appreciate your comments, but the attack and prohibition of leaded fuel is a "when" not "if" situation. my bet is within 10 yrs

[Andy_RR]

I have heard, and I'm happy to be corrected, that there is only one plant in the whole world producing TEL now - based somewhere in the Midlands, in the UK and run by Associated Octel, I believe.

Now, that's a bit of an 'eggs in one basket' scenario, isn't it? There only has to be a bit of an environmental upset there and the place may get shut down. It will put a hole in the AVGAS supplies - already a bit random within Europe - in short order.

Anyone know anything to the contrary?

A

[RVbySDI]

The issue with conversion is going to be driven by money, period, end of sentence! The current fight is motivated by money. Tomorrow's objections will be motivated by money. It will cost to have an airplane function differently than they currently do. Whether that means changing minor things like gaskets and seals that will cost a few hundred dollars or whether that means changing major things like a new engine in an old airframe that will take tens of thousands of dollars.

The lubrication issue may be the relevant technical problem to overcome but the fight will be against spending all of that money to make the change happen. That is where the true resistance to the change will come from. The auto industry rebelled against the changes but in the end the change occurred. And may I add, I believe for the better. The tide was turned after much government pushing of the large corporations in that industry. That will eventually happen in this industry too. The difference is going to be how tightly the existing pilots and owners of current aircraft are going to hold on to their wallets.

[frankh]

I highly doubt it. I think this is an OWT (old wives tale). This may have been true 20 years ago when soft valve seats were the order of the day but todays Lycomings (and clones) all have hard valve seats, thats why the clone suppliers are saying "yes" to premium unleaded.

I agree for some really ancient engines (I'd pity the radial engine owners) with the old soft valve seats it would be an issue...Nothing that can't be resolved with a simple AD right?...

Frank

[AlexPeterson]

This thread may set records...

Others will certainly comment on the lead as lubricant issue...

My angle is more political - There may be billions of dollars worth of engines which would be "decertified" if LL went away, but that is a spit in the ocean when it comes to national politics. Technical accuracies are obviously not part of national politics, as many examples can prove.

Everything will come down to how much money aircraft interests can send to politicians to keep the inevitable ban on lead from happening sooner rather than later. And, not just how much money, but how much compared to the environmental lobby. And, given recent events, the courts may simply mandate lead's removal without concern for Congress or the citizens. This will be a formidable effort....

Thankfully, most RV's will probably be happy with autogas.

[the_other_dougreeves]

Originally Posted by Low Pass

I appreciate your comments, but the attack and prohibition of leaded fuel is a "when" not "if" situation. my bet is within 10 yrs

I agree. It's not a question of when. So, we need to plan for the disappearance of 100LL sometime in the future. 10 yr is a good guess.

However, as others have noted, it all comes down to money. It's entirely possible that we could see a different tax on 100LL than MoGas / UL96. Another possibility is that the price of TEL goes up. But MoGas is normally cheaper than AvGas most places, so there is already a reason to use MoGas.

Lots of new aircraft engines run fine on MoGas / 96UL. Many Superior and other LyClones like MoGas, including the certified Vantage engines from Superior. Many "alternative" engines run better with MoGas, e.g., Rotax 912 series. Heck, Formula 1 runs with 102 octane (RON figure, measured just like AvGas), and they get ~800Hp out of 2.4 liters... Lead in fuel is not a limiting problem in engine design.

So, we can wait and fight/delay/deny or we can prepare. I've voted with my money and have a MoGas-compatible airplane. My next one will be too.

[hecilopter]

I bought my Superior engine because it was approved for 91 octane Mogas just in case. Then they promptly added Ethanol to all gas sold in Texas. Killed that one off before I ever even tried it!

[frankh]

Still have not heard an argument that makes sense as to why you can't have ethanol mixed with the gas....Not extolling this as a reason to go out an try it just haven't heard why it won't work.

Frank 7a

[phil9diesel]

When pilots stop at certain airports, they sort-of apologize for not buying the pumped gas. Leaded aviation gas, maybe 20 years ago, became only-very-leaded-gas. 100LL or nothing. Airports are not neccessarily easy businesses to maintain, and owners hate to be put on the spot for another liability, so they're leery about supplying no lead for grounds equipment and other things. Home refueling prevails, but there are amateurs. People who very infrequently fly, can't drain 100LL into modern emissions cars, without causing damage. Stale gas is slated for the wild blue yonder. Not many passenger planes need boosted octane, and the physical lubrication baloney about leaded gas has balloned into an emperor's new clothes charade. Because 100LL is a metaphor for FAA inspection and bonus cash, even aero engine manufacturers have to advocate lead. Let's have safe gas without lead, more universal fuel supplies, and refueling at our favorite airports.