AVmail: July 7, 2008

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The Demise of 100LL

For at least 10 years, that I know of, the use and future availability of 100 octane low lead (100LL) aviation fuel (avgas) has been "under attack." For example, the U.S. Environmental Protection Agency (EPA) has been giving users a "pass" to continue using 100LL avgas with the caveat that the GA community and suppliers try, in earnest, to find a suitable alternative. That "pass" is up for review periodically. Though the EPA is certainly a threat to the continued use of 100LL avgas, the bigger threat has always been to the supply; in particular, the "silver bullet" additive: tetra-ethyl lead (TEL). TEL's superior ability as an "anti-knock" agent is unsurpassed. Currently, there are only a couple of known manufacturers of TEL remaining, and one of those (a major supplier) expects to be out of the TEL business around 2012 or so (based on what it's been telling it's concerned stockholders). Since TEL has a short "shelf-life," breaks down readily in sunlight, is deemed highly toxic, and the only remaining demand is from the users of smaller, piston-engine aircraft, the economic pressure to stop production of TEL is mounting. Over the past 10 years, many approaches to find that "silver-bullet" replacement for TEL have yielded virtually nothing. Many "exotic" additives have been tested (some even more toxic than TEL) but none could not come close to replacing TEL's anti-knock capability. However, while many researchers were looking for TEL's replacement, some researchers (including those at the FAA's Technical Center) were taking a different approach to the problem: Determine the actual octane needs of the GA piston fleet. As it turns out, a vast majority of the GA piston fleet's octane requirements are something significantly less than 100 octane - around 93 to 94 octane, depending on whom you talk to. Achieving a 94-octane "super-distillate" without the use of any additives is being done today. Admirably, Lycoming is finally taking steps to get many of its engine models FAA-certified for lower octane avgas use (AVwebFlash, June 4). Of course, this also requires the "airframers" like Cessna, Piper, Cirrus, et al., to have their aircraft with those engines similarly FAA-certified ... a daunting task, to say the least. Sure, there are many GA piston engines that require 100 octane (for example, the engines found in the largest Cessna and Piper singles and twins). However, there are computer-assisted electronic ignition systems under development that show promise in eliminating the "knock" caused by the use of lower octane avgas. It appears that the coming demise of 100LL avgas will not be the demise of GA ... but there are certainly other factors that may. Lance Nuckolls

Fuel Prices

You pilots in the U.S. are lucky that you still have fuel prices that you can afford to pay, like US$7 a gallon (QOTW, June 25). Brace yourselves for a shock now! 100LL in Greenland costs (at the current exchange rate) US$13.72 a gallon, so I am actually happy on the behalf of U.S. pilots that they don't have to struggle with the high fuel prices we have here and in Europe. Here I think is probably the highest in the world. Allan Larsen
I really envy you guys ... avgas for less than $6.00 on average. We are currently paying $13.75 here in Germany (most of it taxes) and it is continuing to rise. But we keep on flying, though at a sharply reduced rate. That's why the diesel engine is so popular over here and Thielert's troubles are deeply disturbing. Juergen Boettcher
The price of fuel is only one of the reasons I quit flying. Everywhere you turn, someone else has their hand out! Also, I am a certified A&P and I have been so long enough to have my own number (not SSN). Now, we can't fix things anymore ... it is always "replace," regardless of cost. I have a Cessna 150 and the seat pans have cracks and those have been repaired. Now the rule is, "If there is a crack, replace the seat pan!" All the "replace this" and "replace that," plus the costs of fuel ... I quit. John Newman

New AOPA President

Just read your news release regarding the appointment of Mr. Fuller as the next AOPA president (AVwebFlash, June 30). To say I'm disappointed would be a gross understatement. His pedigree and credentials lead me to believe that he aided and abetted in development of some of the worst political policies our country has experienced. Don't expect him to change his "stripes." Bob Jones


Referring to the Eric Rupp flight in the DG 300 of 444 miles (AVwebFlash, June 29). A German flew 3,018 km several years ago as a world record. That's about 1,886 miles! Ray Kleber

D-Jet Video

This was very professional and the type of video that makes me glad I pushed the play button (AVwebVideo, June 30). Nice job. Dan Cornell

Electric Planes

With regards to your latest question about electric planes (QOTW, July 3). We, in general aviation, need to get onto the latest bandwagon (hybrid aircraft) vs. this latest "pie in the sky" idea, electric aircraft. This may sound rather harsh, but maybe I should rephrase my statement and say we should "explore" the more technically obtainable hybrid package vs. the all-electric aircraft. Most of the engineering has been done by the auto industry (i.e., the batteries and regeneration procedures, etc.) What some enterprising folks need to do is to harness the potential of the air we fly in to turn an electric charger (a ram-air design) and reconfigure the propeller with a flywheel that can use the "electrical" potential in the cruise mode. We need to keep the engine (albeit we could reduce its size and fuel consumption) to provide the power for taxing, take off and as a back-up for landing. Just a more "real-world" approach than the "Star Wars" all-electric idea. Mike Munson
For me, four hours on a charge would be too limiting. I might need to fly six or seven hours in a day (add an hour reserve!), so eight on a 10-hour charge would be OK. That means solar cells on the wing, I suppose ... Jack R. Lewis

Medical Helicopters

The "elephant in the room" regarding medical helicopter crashes is the medical necessity for most of these flights in the first place (AVwebFlash, June 29). Transporting a sick or injured patient is glamorous, high-tech, dramatic, etc. But is a helicopter flight always necessary? A journal article published in Trauma a while back looked at this question and concluded that over half of the transports by air could have been done by ground. Hospital systems are competitive enterprises and strive to show the public that they are modern, high-tech, and justify their helicopter programs as an effort to "save lives" whenever questioned. But they simply pass on their costs to us, the general public, through insurance premiums and taxes, so they have a blank check to operate these very expensive programs. Yes, there are always anecdotes where an air transport actually did make a difference; but when a critical examination is made, these are the rare exceptions rather than the rule. Gary Johnson

Picture of the Week

Something about the first-place photo this week looked really familiar to me (POTW, July 3). A very similar photo won POTW a while back (the tail numbers are different) (POTW, May 23, 2007). It's a great shot nonetheless, and I'll be adding it to my screensaver rotation. Jim Lin
I am a semi regular contributor to Picture Of The Week, I have won it twice the past two years and my son won it once this year. I wouldn't go through the trouble of an email if I didn't think you guys totally blew it this week. The photo from "Lake Hood Sunset" by William Johnson of Fairbanks, Alaska, was easily the most beautiful and dramatic, easily topping all other photos. Such a wonderful photo, but at least he made the slideshow. The F-15 winning shot, though very nice, is a typical airshow afterburner photo pass, whereas Mr. Johnson's sunset shot is a one-of-a-kind, unique picture. Please pass my appreciation on to Mr. Johnson and, if I had his address, I would send him one of my AVweb POTW hats. Still a great contest I enjoy to participate in and view weekly. Jeff Randall

Looming Pilot Shortage

I know Karen Kahn would like to sell her books and book speaking engagements (AVwebPodcast, June 30). But how could you even advertise about the "looming pilot shortage" when every major airline is cutting pilots at 1000 a whack? In March, four airlines went out of business. Where is the shortage, because I'm looking for flying jobs. She must be talking about overseas, as in China and India. Steven Brower

FAA EASA Deal Signed

Did you know that the EASA deal is not a two way street (AVwebFlash, July 1)? TSOs and STCs from the U.S. do not have to be accepted by EASA. However, EASA TSOs and STCs do have to be accepted by the FAA. Harmonization only if you sing in French or German. We can thank our State Department for their wonderful negotiating skills. Mitch Oomens
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