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AVmail: June 14, 2010

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Each week, we run a sampling of the letters received to our editorial inbox here in AVmail. One letter that's particularly relevant, informative, or otherwise compelling will headline this section as our "Letter of the Week," and we'll send the author an official AVweb baseball cap as a "thank you" for interacting with us (and the rest of our readership). Send us your comments and questions using this form. Please include your mailing address in your e-mail (just in case your letter is our "Letter of the Week"); by the same token, please let us know if your message is not intended for publication.

Letter of the Week: The No-Lead Threat

Finding a viable replacement fuel for leaded avgas looms as a catastrophic threat to high-performance piston aircraft owners, and PA-46 aircraft in particular. The threat is two-fold:

  1. The lead additive to avgas which boosts its octane from ~93 to over 100 is tetraethyl lead (TEL). There is only one remaining supplier worldwide for this additive. Were TEL to become unavailable from this source for any reason, our fleet would be immediately grounded. Given the relatively small market that avgas represents in the worldwide petroleum industry and the eco-political status of leaded fuels, it is doubtful that that another supplier for TEL would materialize.
  2. Political cover for general aviation to continue using leaded avgas is quickly disappearing. The EPA is being pressured by ecological groups to immediately eliminate lead from all aviation fuels and has released a pre-publication version of an Advanced Notice of Proposed Rulemaking (ANRPM) on lead in avgas. The ANPRM signals the agency's intent to investigate lead emissions from general aviation aircraft further under the regulatory processes of the Clean Air Act.

On May 13, Teledyne-Continental Motors (TCM) announced that it is backing 94UL as the replacement for 100LL avgas. 94UL is the same as 100LL but without the tetraethyl lead octane enhancer. TCM claims that all of its engines already certified to run on 80/87 octane will still provide rated power with 94UL and that its turbocharged low-compression engines will also experience no drop-off in performance. Others knowledgeable in this technical area strongly disagree with TCM's claims on turbocharged engines such as those in the Malibu.

On June 6, from AVweb, we learn that Lycoming has taken an opposing view, insisting that only a 100-octane solution should be considered. According to Lycoming's GM, Michael Kraft, "If people really understood what's going on today, they would understand that we need to set the objective at 100 octane fuel."

There are currently at least two 100-octane fuel alternatives, and maybe more in development. What is clear is that while lower-performance engines will run fine on 94UL, higher performance engines such as those used in the PA46 Malibu, Matrix, and Mirage will not. Reducing the detonation margin in the engines would necessitate reduced output with corresponding degradation in performance, resulting in dramatic reductions in utility for our aircraft. In most cases, this would, at a minimum, require a significant reduction in gross weight due to reduced climb gradients from lower horsepower engine output.

Of greatest concern is that we run the risk of this decision being primarily influenced by the engine manufacturers with limited input from current avgas users that is, us, owners of high performance piston aircraft. Unfortunately, individual aircraft owners seem unaware of the threat this issue represents and, to this point, have been mostly silent.

As President of the Malibu Mirage Owners and Pilots Association (MMOPA), I consider this issue to be both important and urgent. The certification of a fuel of less than 100 octane would instantly and adversely impact our membership in a dramatic way. I will be writing letters to the engine manufacturers, ASTM, FAA, DOT, EPA, and AOPA to state our concerns. I will also be looking for opportunities to network and partner with other type groups who share our stake in the matter.

What can you do? Look for opportunities to awaken general aviation pilots to the critical nature of this threat. Write your own letters. Express your concerns to those groups with political access and influence, such as AOPA and EAA. This is not just a PA46 issue.

Jonathan Sisk
President, MMOPA Board of Directors


Back to Two Aviation Fuels?

When I started flying, the normal fuel available included both 80/87 and 100/130. The transition to a single fuel, 100LL, took place while I wasn't watching, so I don't really know why it did.

With the pending demise of 100LL, it seems to me we once again should have two different fuels available at most locations. 94UL is ideal both technologically and cost-wise for many light planes. However, some higher performance engines require higher-octane fuel, which will certainly be a lot more expensive than 94UL.

I know FBOs face some cost issues to get two different fuels going again. I have already suggested my local airport authority (a local government entity) budget for an additional fuel tank and pump. Perhaps it is time for a "movement" to get other airports back into the two-fuel business.

Paul Mulwitz


Rank Rankle

What's wrong with this story (A First For Female Air Force Pilot)?

It's a great story of a very fine career. But check the last line of the first paragraph: "Dunlop will succeed Brig. Gen. William Thornton to assume her latest command."

Does this mean the Air Force is filling positions staffed by male Brig. Generals with female full-bird Colonels? What about the "equal pay for equal work" ethic?

Let's hope Col. Dunlop receives the rank she deserves and is promoted to Brig. General soon.

Glen Coombe


Just For The Rich?

This is a rebuttal to the letter titled "ADS-B Whiners," by David Rosing.

I own a 45-year-old Cherokee that is very airworthy, and I know many pilots of similar aircraft. I will bet that none of them can afford a new engine at any time. Most of us do not have panel-mount GPS units because of the ridiculous cost. To install, say, a Garmin 430 would cost me about half what a new engine would. I guess, based on that, I cannot afford my aircraft, as Rosing implies, and I would bet most owners fall into that category.

Our concern about the ADS-B out requirement is cost. The cost of the needed equipment could be so onerous (because we own a "certified" aircraft) as to force us out of the sky. Maybe aviation is only for the rich.

Barry Roberts

To a degree, Mr. Rosing has a point but his choice of the word "cheapskates" is regrettable and most unfortunate.

There is a big difference between being financially challenged and being a "cheapskate." It is one thing to say that a person cannot afford something, but it is something very different to say they are a "cheapskate."

Cheapskates have the money but cut corners they even cut back on safety (and not only their own safety) to keep as much money as possible for themselves.

Aviation has its share of "cheapskates" also a quantity of "elitists."

I suggest that to imply being financially limited makes a person a "cheapskate" is offensive.

Charles Elliot

David Rosing is way out of line. It's not about whining because we need to spend money; the whining is because we are spending money without any benefit. This is typical government operation: They are not the ones writing the check from their bank account; they just mandate it without just cause. I surely hope David is not in any position to make rules, as he is way out of touch with reality. A $10,000 expense in a $30,000 plane without any benefit? No way, no how!

Rick Martin


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