Piper Completes Flight Tests of Archer Fueled by 93 Octane
Big news out of Florida, as Piper Aircraft has announced that they successfully completed the first flight of one of its Archer aircraft using 93 octane premium unleaded automotive gasoline. Here is a link to the official announcement: http://tinyurl.com/ls74hv4
Does your closest FBO offer 93 octane already? Check it out here: http://www.globalair.com/airport/
Doesn't seem like it should be a big surprise here.
I've been running on auto fuel for 20 years. These 1930 technology engines don't really care what they burn.
We used to have an old tractor that started on gas and then chugged away all day on diesel fuel. Low compression and spark plugs.
Heres the funny part. In the non-aviation engine design world, we wish that all gasoline was along the lines of 100LL or slightly lower octane UL version, and that we werent stuck with this variable garbage called auto-fuel. All the constantly varying chemistry that may be fine one month, but next month is destroying fuel system parts, or knocking a high output engine to death. In all seriousness, the GA community has no idea how LUCKY they are to have something as nice as 100LL.
Yea... How lucky we are to pay $6.00+ a gallon for AV gas, vs. $3-4+ a gallon...
It adds up really quick, for those of us with shallow pockets, trying to escape the bonds of earth, once in a while.
Yea, how lucky we all are...
Damage costs from cheap automotive fuel also add up. Many non aviation engine manufacturers will test run their engines on 100ll or some other specialty fuel before shipment, just to avoid the failures caused by mo-gas. It is a constant battle, and is only getting worse. Im not even talking about ethanol here...Originally Posted by I_FLY_LOW
Ray, that webpage lists "mogas" but does not tell the octane rating. The closest airport to me with "mogas" is GIF with $5 100LL and $5 "mogas" of unpublished octane or ethanol content. The next closest is SEF with $5.30 100LL and $5.75 for whatever their "mogas" is. Why fly all the way there expecting to pay the same or even more and not be sure if what they have for sale is adequate? Don't bother replying "phone first" because I've found a phone promise often doesn't meet the pump label.
Put another way, I've been burned on crosscountry trips by expecting to get what i needed and finding it was not really as indicated. and that was when i had an airplane that only needed 80 octane. now that i NEED 91, flight planning to a place listing generic "mogas" is not an option unless they back it up with 100LL at a competitive price. which, thankfully, SEF and GIF can do. but there is no $ savings there unless flying a rotax and trying to use longer oil change intervals. big whoopee.
For local flying, try pure-gas.org
Last edited by Mike M; 08-09-2013 at 05:35 AM. Reason: spelling
My Lyc O-320, per the manual, said to use 87 octane, unleaded.
We usually used the then $1.89 / gallon 100LL, but always ran TCP (lead scavenger) in every fillup.
We did do some bulk auto fuel for a while, until we got tired of the handling of it.
The plane ran fine, on either fuel, and saw no change in fuel economy between the two.
If I were going to use auto gas now, which I may very well do so, when the time comes, it will be non-ethanol.
We have several stations scattered around where I live, that sell the non-e fuel.
The rest, so far, are 10%E.
I ride motorcycles, also, and avoid the stuff in my bikes, and lawn mowers, at all costs.
There's no mystical, magical aircraft engine only elixir to it.
Yes different branded stations have their own additive packages that are added usually right at delivery time, but very little else is different.
The only variable, is the onsite storage, like mentioned before, with the allowance of moisture in the fuel tanks, and any other trash that may be in there.
With the exception of the excessive water content, usually fuel filters catch the majority of whatever other contaminants may be.
I've never in all my years of driving, or flying, wound up with a bad batch of fuel.
I'm pretty cautious about where I purchase fuel, and feel that may be a reflection of the quality of the fuel I've purchased over the years.
Interesting reading, very informative.
I have a 300 gal tank in my hanger which a bulk dealer fills for me, I use high octane and test for ethanol each time. So far nothing has appeared. I also fire sleeved all my fuel lines and have never had a problem. I live in the north where we seldom get above 80f so I don't believe vapor lock is an issue.
What I take from what I have read is that auto gas has higher volatility, it evaporates quicker which would make it "better" fuel as only gasoline vapors burn so the easier it evaporates the easier it will burn?
Incorrect,
Engines dont run on "vapor", they run on atomized liquid droplets for the most part. There are "light ends" in the fuel that will vaporize, and this is to help cold ignition. With auto fuel the vapor pressure varies with the season, meaning that in winter the fuel has more light ends to help cold start, in the summer less to avoid vapor issues. Here lies much of he issue, the ever changing chemistry and the random addition of various light solvents like toluene. Part of it changes in the pipeline, part of it is up to the individual station. From a design standpoint, trying to design and calibrate an engine for auto-fuel is like hitting a moving target in the dark. From the outside to people that dont know engine design, it does not seem like a big deal though, and I think this is where a lot of arguments come from. Either you understand it, and know what will be required to deal with it, or you dont understand it and think everything will work just fine all the time.
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