Auto Fuel STC future

[Throttle Pusher]

I was cheating on this site with another site, and over there they were having the same discussion. Someone(over there) brought up the fact? that E-30 has the same VP as strait gas does.
Any thoughts or great wisdom to back this up or ridicule it from here?

Cheating Ken

[andya]

have 2 friends that us auto gas in their birds. One is a Varga with the same 150 HP we use. He had the engine quit on takeoff coming out of a desert strip last year. After the abort, he restarted and all was well. He assumed vapor lock.

The other fly's an RV with an O-360 with Bendix RSA-5 injection. he uses auto gas in one tank and avgas in the other. While doing aerbatics this summer on the auto gas, he started loosing power. engine would quit in approximately 30 seconds if he didn't turn on boost pump. getting the pump on as soon as he noticed any loss, solved the problem. he started experimenting with a mix of auto and car gas in the same tank. Can't remember the ratio ( I think it was about half and half) and this seem to solve the problem. For take off, climb and landing, he only uses the tank with Avgas.

[kloudking1]

Since I don't know very much about the chemical properties of the two fuels, (100 LL or Mogas), I will say that I put ethanol enriched gas in my lawn-mower and I have to overhaul the carb each summer. The fuel bowl gets rust in it and the passages get crap in them, so I have to pull the carb off and go through it. I have found a source for ethanol-free gas and am now using that in the mower and boat, but I still use the cheapest gas I can find for my truck. In the Colt, I will be using 100LL.

[Gilbert Pierce]

I think it is unconsieceable that the FAA failed to include Auto Fuel STC holder's, Experimental Aircraft and LSA's as being authorized to use Auto Fuel.
Gilbert.

Latest FAA fleet fuel report deeply flawed

Kent Misegades | GAfuels | November 28, 2011
In November, the FAA published its latest “Reciprocating Engine Aircraft Fleet Fuel Distribution Report” DOT/FAA/AR-TN11/22. As described in the report’s abstract, “The purpose of the data analysis was to establish a baseline of aviation fuels currently in use by all reciprocating engine-powered aircraft to quantitatively assess the effect of first reducing and, eventually, eliminating the tetraethyl lead content on the population of aircraft currently certificated by the FAA.”
Incredibly, the report states that “Only 0.4% of the aircraft are approved to use unleaded fuel.” On further study, the report reveals that its authors were allowed to report only on fuels specified in aircraft Type Certificates, completely ignoring the fact that some 60,000 Supplemental Type Certificates (STCs) have been issued for lead-free autogas since 1982.
Furthermore, the report misses over 2,200+ new S-LSA aircraft that are best operated on autogas. Since LSAs are issued a Special Airworthiness Certificate as opposed to a Type Certificate, they were not counted, although they qualify as reciprocating engine-powered aircraft.
None of the estimated 30,000+ homebuilt aircraft that have been registered in the E-AB category appear in this report, and it is known that many are operated regularly on lead-free autogas. The report also makes no mention of an array of new, autogas-burning aircraft engines that power these LSAs, as well as higher performance aircraft, including the latest generation of products from Continental and Lycoming.
At best, this report is deeply flawed; at worse it was intended to create a skewed baseline to justify continued use of 100LL/100VLL longer than is necessary, given that — in reality — between 70%-80% of all piston engine aircraft are capable of operating on 91 AKI lead-free, ethanol-free autogas, an FAA-approved aviation fuel since 1982.
We strongly recommend that the FAA revise this report to include all reciprocating engine-powered aircraft, including TC’d, STC’d, E-AB, ULs, LSAs, rotorcraft, motorgliders, etc. Otherwise it is essentially worthless in its current form.
The GAfuels Blog is written by two private pilots concerned about the future availability of fuels for piston-engine aircraft: Dean Billing, Sisters, Ore., an expert on autogas and ethanol, and Kent Misegades, Cary, N.C., an aerospace engineer, aviation sales rep for U-Fuel, and president of EAA1114.

[RobertC]

Two comments about this thread.
1. I wish I hadn't cheated in high school chemistry.
2. If this is where the intellect level of this site is heading, I'm going to need tutoring.

[danP]

OK, I just made my run for my customary 15 gallons lead free/ethanol free mogas for my tripacer. I have access to either 87 or 91 octane versions here. And the question came up in my mind again; "why is there such an effort to develop a new aviation fuel when 91 lead free/ethanol free fuel is already an option? does the fuel need to be 100 octane?

[Pacer20]

High compression engines require 100 octane to prevent detonation. I believe a larger percentage of the GA fleet is low compression and does not need it.

[Gilbert Pierce]

The reason we need 100LL according to the experts is 80% of us can use auto fuel but we only purchase 20% of the gas at the airport. 20% of the airplanes, big twins and high dollar Cirrus etc.need 100LL but they buy 80% of the fuel. It's a money issue. You put on your shelves or in your storage tanks that product that sells the most.

[Throttle Pusher]

If it was cheaper we would buy more.

[Bob.shea]

I run clear gas ethanol free 91 octane I will mix in LL100 if I have to, but a 150 hp is low compression and will run fine on this fuel. Shell has a clear fuel that they are testing now, It is to be a across the board replacement fuel. Lets hope it out before clear gas is no longer available. My STC states ethanol free auto gas so since that has been test and approved by guys smarter than me I will trust there judgment. Happy Holidays everyone