fuel

Part of every piston-pilots preflight ritual is sumping the fuel tanks to check for water. Given that a modern Cessna has 13 of these fuel drains, wouldnt it be better just to keep the water out? Thats what Stay-Sealed attempts with a fuel cap to put in place over your existing fuel cap. The company offers covers that fit most single-engine Cessnas and Pipers. The covers arent interchangeable, so order the right type for your airplane. The cap is applied by pressing down and physically locking over the existing fuel cap. You need to pull up on the ring at the center to make sure its really in place. It shouldnt pop off. The company claims it will stay on in an 80 mph wind. It comes off with a slight pop when you pull from the corner with no scuffing to the paint. We tested the Stay-Sealed cover on two high-wing Cessnas by smearing a paste that changes color in the presence of water just inside the filler neck, closing the cap and then drenching the wing until there was standing water. We tried it with an unprotected fuel cap, a canvas aircraft cover and the Stay Sealed cover. (A big thanks to the folks at Cumberland and York Aviation in Biddeford, Maine, for their help with this.)

Ten years ago, when avgas prices soared to the point of being noticeably painful, fuel costs were still the smallest percentage of total operating costs. In an era of $5-plus avgas, thats less true for owners who operate airplanes burning 8 GPH or more. So now, the question is no longer how to find cheap avgas-there isn’t any-but how to avoid getting your eyes gouged out on a typical fill-up. An unpleasant reality is that avgas prices have become wildly spiky from airport to airport-its not unusual to see a $1.50 or $2 difference between airports in the same region or even across town. Our favorite example is the poster child for high gas prices-Jet Aviation in Teterboro, New Jersey, which was charging a salty $8.68 at press time. Yet 21 miles away, Greenwood Lake Airport was asking $5.36 for a difference of a whopping $3.32. For a modest fill-up of, say, a Cessna 172, that amounts to $116 total. For a big single, its more like a $250 and a total charge of $650. Owners who travel with their airplanes by necessity have to plan around high fuel prices-forget winds and weather; find an airport with affordable fuel. But whats the best way?

Not to alarm you, but the highest price avgas in the U.S. recently topped $8, although the average hovers closer to the mid-5s. Long before this distressing development, a reader wrote with this suggestion: “You know, you really should look at the fuel economy of various airplanes. Im beginning to wonder if there’s a big enough mileage difference to make it worth looking at something else.” Answer: We can, we have and there is. A certain class of owner-OK, the cheap screws-have always considered fuel efficiency above all else, either because they don’t have to carry much in the airplane or they don’t want or need to go fast. Of such stuff are Mooney owners made. (And we can prove it.) Since it costs $250 to fill up a Cherokee, more owners than ever are dropping back to survival mode and asking what kind of capability 8 gallons an hour will buy. (More than you think, perhaps, but in any case better than padlocking the hangar door.)

Give pilots and aircraft owners credit for one thing: It takes a strong constitution to remain functional and focused when the avgas truck creaks to a halt and you realize that what you thought was a 5 on the price placard at 100 yards was actually a 6. So you whimper softly and pay the man, perhaps salving yourself with the idea that the new Jet-A burning airplanes will make this nightmare go away. But will they really? Are diesels that much more efficient than gasoline engines? Yes, possibly. But it depends on the engines being compared. When it comes to efficiency, Lycoming and Continental are not created equal. But the larger issue-and whats driving the Jet A piston revolution-is that Jet A-burning pilots (piston or turbine) neednt get their pants snagged worrying about their fuel being phased out in 10 years. They can also count on it being available in every country on the planet and at ever more airports. And thats why we write stories about Jet A piston engines, not because theyre cheaper to operate-they can be-and not because theyre more efficient-they are, but not as much as you might think.

When famed researcher-and inventor of the electric starter motor-Charles Kettering discovered that no compound worked as we’ll as tetraethyl lead to kick up the octane of gasoline, he couldnt have guessed that nearly 100 years later, science would still be looking for something almost as good. That the search hasnt born fruit is one reason-although not the only one-that we still fly behind magnetos, not the electronic ignitions that have been commonplace in cars for three decades. Its not for lack of trying. Teledyne Continental has had a certified FADEC for piston engines for some eight years, homebuilders fly with various iterations of electronic ignitions and General Aviation Modifications intriguing PRISM system thus far exists only as a test article. And the tests confirm that these ignition systems can prevent detonation in high power engines burning lower octane unleaded aviation fuels. So whats the problem?

Twice a week. On average, thats how often GA pilots run out of gas. One reason for this-we surmise-is that pilots either don’t know how to manage fuel or they just do it poorly. The iffy gas gauges found in typical legacy airplanes aggravate the problem. Although the real reason for fuel exhaustion lies between the pilots ears, there’s a not-too-expensive upgrade that can help: a fuel totalizer. It will provide instantaneous fuel consumption data along with fuel remaining, endurance and, perhaps most important, a reliable indication of lean state. With gas at $6 a gallon, you need all the help you can get. When connected to a loran or GPS, a totalizer can supply distance-to-empty and reserve-at-destination information, along with your real-time mileage. Most fuel totalizers are stand-alone products; others require either a compatible GPS or an installed engine monitor to do their thing. Either way, none will guarantee you wont run out of fuel, but you’ll have to work at it.

During a typical pre-buy inspection or an annual for that matter most of the expensive scrutiny is aimed at the engine, that pricey lump of parts that can soak up money like a dry sponge in water. No one thinks much about fuel tanks, bladders and wet wings because, well, they arent very sexy.

Its economics, mainly. There’s no discernible push to eliminate lead from avgas and as long as money is being made, the alternatives are simply DOA.

Weve been writing sky-is-falling stories about the demise of avgas for 20 years. Heres why its still around.

After some tweaking, GAMIs precision nozzles knocked a couple of gallons off fuel flow and tamed spikey temperatures.

When we reported on the improved fuel injection nozzles made by General Aviation Modifications two years ago, we got a steady trickle of testimonial letters affirming that, yes indeed, these devices work as claimed.

But also some complaints: Why no nozzles for Lycomings? The simple answer is that GAMI is a small company and couldnt get around to the R&D work until about a year ago. (Besides, GAMI figured Lycoming engines wouldnt benefit as much from improved nozzles, a notion that turns out to be correct by degree.)

In any case, GAMI is now delivering improved nozzles for most Lycoming engines. These range in price from $699 for normally aspirated four-cylinder engines, $899 for tur…