Ethanol fuel and deteriorating composite fuel tanks
Mark
has ethanol in it then you should google something like the
following...
ethanol fiberglass fuel tanks
There you will find out that the ethanol content appears to be a
significant player in relatively rapid deterioration of the resin and
therefore early failure of the fuel tank
Looks like the boaters have been seriously affected by the E10
situation and if your motorized sailplane also has a composite tank it
may be at risk of early failure.
AVGAS probably doesn't have Ethanol added so if you have a composite
fuel tank, it may be very wise to only use AVGAS even if autogas w/ 2
cycle mix is allowed.
aero...@socal.rr.com
> If you have a composite fuel tank and the fuel available in your area
> has ethanol in it then you should google something like the
> following...
>
> ethanol fiberglass fuel tanks
>
We stopped runing mogas in our STC'ed pawnees when CA Dumped MTBE and
went to 10% ethanol a few years back, Concern was more on the other
elements of the fuel system, I think the early Pawnee fuselage tank is
polyester.
aerodyne
Darryl Ramm
I think you want to be concerned with Polyester resin based tanks.
Not a drop of mogas is ever going in my ASH-26E, for possible tank
problems with Ethanol and other reasons including engine cooling.
Darryl
aero...@socal.rr.com
Polyester resin based composites have been used for underground mogas
storage tanks (gas stations) for decades. Polyester and vinylester
are very chemical resistant.
aerodyne
Darryl Ramm
Polyester based fiberglass tanks are exactly amongst those causing
concern with alcohol based fuels. You run it in your motorglider, I
won't in mine.
http://lmgtfy.com/?q=alcohol+fiberglass+fuel+tank+polyester
Darryl
Mark Jardini
Darryl Ramm
> aren't most of last decade birds built with epoxy resin?
Yes, but what the glider is made of does not dictate what the fuel
tanks is made of. And a fuel tank might well have a special fuel-proof
lining even if the tank is made of other resin. Check with the
manufacturer, and check if they believe the aircraft should use
alcohol blend fuels. And many motorgliders also have aux fuel stored
in the wings - in flexible bags not hard tanks.
Darryl
Eric Greenwell
How about epoxy resin? I think that's what is used in my ASH 26 E fuel
tank. Not that I have any intention using something other than 100LL.
--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm http://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz
Gary Evans
> On 11/18/2010 7:29 AM, Darryl Ramm wrote:
>
>
>
>
>
> > On Nov 18, 7:23 am, aerod...@socal.rr.com wrote:
>
> >> Polyester resin based composites have been used for underground mogas
> >> storage tanks (gas stations) for decades. Polyester and vinylester
> >> are very chemical resistant.
>
> >> aerodyne
>
> > Polyester based fiberglass tanks are exactly amongst those causing
> > concern with alcohol based fuels. You run it in your motorglider, I
> > won't in mine.
>
> >http://lmgtfy.com/?q=alcohol+fiberglass+fuel+tank+polyester
>
> > Darryl
>
> How about epoxy resin? I think that's what is used in my ASH 26 E fuel
> tank. Not that I have any intention using something other than 100LL.
>
> --
> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
> - "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz- Hide quoted text -
>
> - Show quoted text -
Epoxy has a good resistance to alcohol but I agree on the choice of
100LL for other good reasons.
Jim
You spend enough to buy a house on your motorglider and are trying to
save a few bucks on fuel?
Alan
>
>You spend enough to buy a house on your motorglider and are trying to
>save a few bucks on fuel?
Avoiding 100LL is often not about trying to save money.
If you spent that much money on the motorglider, you probably want to feed
it the best fuel for it, which may not be 100LL.
I don't know about the engines used in motorgliders, but the Rotax engines
used in many of the light sport aircraft "prefer" mogas over 100LL, as the
lead content results in shorter service intervals for things like oil changes,
gearbox servicing, and possible engine overhaul.
Alan
Nigel Cottrell
unleaded is unavailable due to increased wear and unsuitability
to their 2 stroke engines. We have never used 100ll in our 505
due to this advice from Rotax.
The sooner an unleaded aviation petrol spec is agreed and the
fuel widely available the better.
This would also be of great help to the large number of light
aircraft powered by engines originally designed to use 80/87.
At 07:11 19 November 2010, Alan wrote:
Darryl Ramm
Ah the devil is in the details and the question about concerns with
Ethanol blend fuels that are an issue in the USA may not be in the UK.
The real question is what do Rotax or the aircraft manufacture say
about Mogas with Ethanol blends? And what experience do people
actually have operating at high Ethanol blends E10, E15 etc. Its not
just an automatic extrapolation that because non-blended or low-blend
(<5%) Mogas is "better" (for some definition of what better means)
than 100LL that all ethanol blends of Mogas will be. In many cases I
suspect that the motorglider manufacturers do not have enough
experience with Ethanol blended fuels to know what the answer should
be.
Let alone the question of what Ethanol blends might do to fuel tanks
and hoses etc. there is the question of whether the Engine and carb
etc. are suitable for higher blend ethanol fuels. To take the example
offered of Rotax/light sport example further Rotax themselves have
qualified some (but not all of their) engines to use up to E10 blends
but no more. Other engines are limited to E5. (see
http://www.rotax-aircraft-engines.com/portaldata/5/dokus/d04851.pdf).
So if you live in the USA in a state where fuel is pushing E15 you
might really want to consider AVGAS.
For example see how Remos handle this issue here
http://www.remos.com/media/news/notification-use-ethanol-blended-fuel
... Use Mogas over 100LL but Mogas is not recommended if it contains
Ethanol. Not exactly clear from this at what blend ratio it might be
better to use 100LL.
The rotary engines in Schleicher motogliders run better on Avgas 100LL
than Mogas so its a non-issue. The Solo engines in DG motorgliders and
others have traditionally had Mogas recommended, but again that advice
may not necessarily apply if the Mogas is a high Ethanol blend. Check
with DG or Binder for their advice - and be clear you are asking
specifically about Ethanol blends not conventional Mogas.
Having drained enough water out of AVGAS tanks in light aircraft to
scare me I would be concerned about dissolved water contamination in
high Ethanol blends.
Darryl
aero...@socal.rr.com
> So if you live in the USA in a state where fuel is pushing E15 you
> might really want to consider AVGAS.
>
> ... Use Mogas over 100LL but Mogas is not recommended if it contains
> Ethanol. Not exactly clear from this at what blend ratio it might be
> better to use 100LL.
>
> The rotary engines in Schleicher motogliders run better on Avgas 100LL
> than Mogas so its a non-issue. The Solo engines in DG motorgliders and
> others have traditionally had Mogas recommended, but again that advice
> may not necessarily apply if the Mogas is a high Ethanol blend. Check
> with DG or Binder for their advice - and be clear you are asking
> specifically about Ethanol blends not conventional Mogas.
>
> Having drained enough water out of AVGAS tanks in light aircraft to
> scare me I would be concerned about dissolved water contamination in
> high Ethanol blends.
>
>
> - Show quoted text -
Alan and Nigel are right, several rotax powered motogliders DO prefer
Mogas. Metal tanks in the HK-36.
Lead in 100LL can cause plug and gearbox problems. I know because I
do the support for two HK -36 research birds
aerodyne
Darryl Ramm
BTW I was not disputing that, but the choice is not automatic what you
should do when higher Ethanol blends are involved, e.g. if the choice
is say between E15 mogas and 100LL avgas? Is it? Rotax says not to use
>E10 in the 912/914 series engines AFAIK. So what do you do, I expect
you are required to run Avgas if the only other choice was E15? At
least E15 should be labeled at the pump, good luck knowing what
exactly you get in many states in the USA now.
But to the point that is is not just "automatically best" to use Avgas
100LL, that is absolutely correct. Owners better read the manual.
Darryl