With auto fuel prices looking like they will be heading towards $3.50 a gallon and aviation fuel probably heading for $5.00+ a gallon. The old Auto Fuel STC might come in handy afterall.

With the damage these prices will envoke upon our economy, looks like our government would do one of two things to help out. Package up a bunch of that Iraqi oil and ear mark it for the U.S. or temporarily axe the 70 cents per gallon federal tax.

If anything, they might have to raise taxes to fund the hurricane relief efforts. My God, this is a disaster of the first magnitude. It was one thing to watch the aftermath of the monsoon in Indonesia on TV-- after all, that's a third world country and them people are used to hardships (just kidding). But to have it happen right here in the US is quite a wake-up call. Turns out a friend of mine was visiting in New Orleans & evacuated to Memphis before the hurricane hit. Another friend lives most of the year northeast of there a ways- he's here now, but can't get in touch with some of his family members down there. He doesn't have any idea if his house is even still there.
I'm not much on the charity thing, but I'm gonna be giving some money to the Red Cross on this one. I also set up & will be taking charge of a donation jar at our local airport cafe, hopefully we'll be able to generate enough to do at least a little good down there.
I'm as unhappy as anyone else about the price increases we'll be seeing,but the way I look at it, at least my home (and my life!) is still intact. NOT the case for a lotta them folks down there!

Eric

What are the drawbacks to running 92 octane in your engine if you have the Auto Gas STC? You always see airplane ads that advertise it has the "Auto Gas STC, but it was NEVER USED." So what are we talking here? Shorter TBO? Less HP?

Zane, you're fixin' to open a real can o'worms! Go to the 170 Assn website (cessna170.org) & search the forums on this subject. You'll see what I mean. People either love it or hate it, very little in the way of indifference. I use it, preferably mixed 3:1 with 100LL to duplicate the old 80/87 avgas as close as possible (as per Petersen Aviation of mogas STC fame). I might even leave out the 100LL if I could get some of that old lead additive that used to be available back when they were phasing out leaded cargas. At say a buck a gallon price difference, you can save quite a bit of money even with the 170's low fuel burn.
But other people I know would be aghast at the idea of cargas in their airplane. Personal preference I guess.

Eric

A lot of aircraft have gone well beyond TBO using auto fuel.

The problem with auto fuel is the quality varies greatly from brand to brand and it becomes stale or breaks down quickly if allowed to sit for any length of time. If you are flying infrequently it's something you want to stay away from. If your flying enough to go through a tank every couple of weeks go for it. The only difference your likely to see is your less likely to foul plugs with auto fuel.

In the winter time, start ups are actually a little easier with auto fuel because of the O2 additives. In the spring time when things warm up these same additives can cause problems in the fuel lines so you need to be careful during the springtime transition when their changing from the winter to summer formula.

There are differing opinions on how to run auto fuel. Some like to run 50/50 Auto fuel and 100LL. Some just run two or three tanks of auto fuel and then one of 100LL to run some lead through the engine. Others run straight auto fuel with a 1/2 ounce or so of Marvels Mystery Oil added to each gallon of fuel and swear by it.

For my use I run straight 100LL in the left tank and run auto fuel in the right tank. Use the right tank for cruising and use the left tank for takeoffs and landings or low level coyote gunning.

The cardinal rule when using auto fuel is to never use auto fuel with alcohol of any kind, which eats away the rubber componets of your fuel system. There is an easy test to detect alcohol in auto fuel. Take a clear tube as in fuel tester and add one part of water to nine parts of the fuel your testing. Add the water first and mark where the water comes up to, then add the fuel. If the water appears to increase beyond the mark, you have alcohol in the fuel.

Next question... Isn't it kind of inconvenient to get the auto gas to your aircraft? Last time I looked there weren't any 92 octane Super pumps on the ramp. Do you just fill your own cans and do it bush style?

Next question... Isn't it kind of inconvenient to get the auto gas to your aircraft? Last time I looked there weren't any 92 octane Super pumps on the ramp. Do you just fill your own cans and do it bush style?

I know a therapist who can help you with that stutter.

Very funny. I got impatient and clicked 3 times. I'll erase one so people get your joke, but so i don't look too retarded.

Wasn't to concerned with the extra clicks but what exactly is it your doing in the avitar photo?

Zane, you can buy a 75, 100, 125, 150, 175 or 200 gallon tank to mount in the back of your pickup for real reasonable at your local industrial or farm supply outlet, add a little electric pump, nozzle and filter for another $125.00 and you have a pretty nifty little fueling unit that will pay for itself rather quickly if you fly on a regular basis.

Also, the Auto Fuel STC for the 150 hp Lycoming only calls for an octane of 87 or above for unleaded auto fuel, so you don't have to run the super/premium if you want to save a little more.

Zane, the cargas STC for the C-145 sez 87 octane ("regular"). And it works just fine. But like Supercubber sez, it has a limited shelf (tank) life. If the airplane's gonna sit unused for long, I'd put 100LL in it- or better yet, 80/87 avgas, but I don't think that's too available anymore.
Some airports do have mogas pumps, but from what I've seen it's generally 87 octane. And udually more expensive than the street price.
When I first bought an airplane, and started using cargas, I was gonna buy a tank/pump for my pickup. The price put me off, so I bought three plastic 5 gallon cans instead. Been using them for 10 years now, no problem. I fill each to 5.5 gallons, so the three cans gives me about 2 hours of flying. Works out pretty well for my local,daily-basis aviating.
No doubt someone else will chime in with all the usual static-electricity warnings. So I won't address it too deeply. Ground the nozzle against the cans (and your pickup) at the gas station, and ground the cans against the airplane wing at the airport. Before any fuel flows.

Eric

Here is the Petersen autogas STC
for the 170B:

DOesn't list the engine types covered.

Here is the <a href="http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgSTC.nsf/STCMake!OpenView&Start=75&Count=200&Expand=81.23#81.23">FAA list</a> i use:

Jr.CubBuilder wrote:Does anybody know offhand if and where there is an online listing of the Peterson autogas STCs? I don't see the 360 Lyc listed on the EAAs list, and I'm really curious if it is covered by one of Petersons.

The Petersen brochure I have (from about 10 years ago) lists a whole bunch of O-360 dash numbers. Most of them require 91 octane minimum. As does the 160-horse O-320. There may be additional requirements depending on the airframe- for example, the Petersen STC for the 160 & 180 horse Cherokee's require that the factory electric fuel pump be removed, and two different pumps be installed. I've heard that a 360-powered 170 STC also addresses the fuel pump issue.

Eric