Waypoints: Running on hope

How about providing a decent fuel-indicating system?

June 1, 2013

Thomas B. HainesWould you ever continue an instrument approach below legal minimums without seeing the runway environment? What would it take for you to make a precautionary off-airport landing—to land a perfectly functioning airplane in a field, causing probable damage and perhaps leading to injury?

As with every debate in aviation, there are multiple situations that might lead to either of the above, but certainly one to consider is an extremely low fuel status—or an unknown fuel status caused by tank leakage or other system malfunction. While fuel systems do fail, the reason we continue to lose an airplane about every five days to fuel problems has far more to do with the highly complex but frequently ineffective system between our ears. But, to be fair, we pilots of legacy airplanes are presented with just about the worst possible information when it comes to fuel status. Sure, a wristwatch works just fine if you’re really familiar with the airplane and its fuel burn at various power settings and atmospheric conditions. But what if you’re not starting with full tanks? OK, use a measuring stick. But, what if you’re flying an airplane, such as a Bonanza, with long, narrow tanks where you can have half fuel left, but no fuel visible through the filler port?

Here’s an idea: How about providing a decent fuel-indicating system? They do it in cars, after all. My 10-year-old car will tell me down to the mile how far I can travel (experience has shown it to be a pessimistic reading—don’t ask how I know this). Here’s the complexity: Cars keep a relatively small amount of fuel in one tank and they travel in two dimensions. Airplanes have much more fuel to manage in at least two and frequently more tanks, and they travel in three dimensions while being jostled in turbulence. Fly a twin? You’ve got even more complexity with the ability to crossfeed tanks.

According to the Air Safety Institute’s Joseph T. Nall Report, we’re losing about 74 airplanes a year to fuel mismanagement accidents. The rate is on a downward trend, as we introduce technologically advanced aircraft (TAA) that have much better fuel-measuring information. But even with good instrumentation, pilots sometimes refuse to believe the reality that engines need fuel and not just hope to run. A Cirrus SR20 pilot pulled the airplane’s parachute and landed in trees just short of Danbury, Connecticut, after reporting that he was out of fuel. Fortunately, thanks to the chute, all three on board walked away uninjured. The airplane—not so much. The pilot had good fuel-indicating information available to him in his TAA, but apparently decided hope might get him back to the airport after a 150-nm flight.

The first piece of gear I added to the 1977 Cessna 172 I bought in 1997 was a JP Instruments EDM 700 engine analyzer—not so much to report on the workings of the simple Lycoming engine, but to get the benefit of the optional fuel transducer, which kept track of the fuel down to ounces. Similarly, the first thing I added to the 1972 Bonanza A36 I bought in 1999 was an EDM 800 analyzer with fuel transducer. In this case, I did care to know about the parameters of the big-bore Continental, but I also felt lost without the highly accurate fuel information because the gauges were extremely unreliable—and they still are. However, when refueling, the amount put into the tanks at top off matches to within a half-gallon the amount the 800 says will be needed. Since then, JPI has introduced the Fuel Scan 450, which only shows fuel information—and does so for less than $1,000. It’s the best “airplane unit” (the financial term I use at home to psychologically soften the impact of airplane purchases) you can spend.

Such information might have saved a newly instrument-rated Piper Arrow pilot who early this year was fatally injured after attempting instrument approaches at four different airports in the Delaware area on a low-IFR day. He had flown all the way from Georgia, and declared a fuel emergency on the last approach to Dover Air Force Base. He didn’t make it to the airport, but crashed instead in a field. Knowing his critically low fuel status, what if on one of the earlier approaches he had made the choice as PIC to descend below minimums and hope for the best? On a well flown, stable approach one could assume that a slow, controlled descent would put one on or near a flat, clear surface in the airport environment—a better choice than an uncontrolled descent through the muck into a random field. Better yet, what if he had noted 100 miles earlier the poor weather and low fuel status, and simply stopped for more gas?

What would you do?

Editor in Chief Tom Haines owns and flies a 1972 Bonanza A36 for recreation and business. Email thomas.haines@aopa.org. Follow on twitter.com/tomhaines29.