Myth busters

Curious, the husband called his mother-in-law. “Because that’s the way my mother does it,” she said.

Finally, the husband called Grandma to get what he hoped was the definitive answer.

“Why do I cut the last two inches off?” Grandma said. “Because when we were first married we didn’t own a pan that was big enough.”

Why do we do so many things that have become common practice in the aviation community? The reasoning that “that’s the way we always did it” has a lot to do with the existence of aerial misunderstandings and, sometimes, downright bad flying practices. Here are 20 pieces of dubious wisdom to reconsider.

“Pump the brakes to keep them cool.” The concept of applying brakes in short bursts of pressure comes out of the time when aircraft had old-fashioned drum brakes: If pressure continued to be applied it would cause them to heat up and “fade,” losing their ability to stop the aircraft. Drum brakes haven’t been a part of aircraft design since the late 1940s, and the disk brakes that replaced them don’t fade when they get hot.

“Fast is good.” Slow airspeed on approach is a bad idea, so many pilots believe that carrying excess speed on approach is a good idea. It’s not. Any speed over the approach speed specified in the pilot’s operating handbook (or 1.3 VS0, if none is listed) leads to excess float and long landings.

“If it’ll fit, it’ll fly.” Exceeding the weight and balance limitations of an airplane contributes to a handful of accidents every year. Extra weight greatly compromises the performance, and moving the center of gravity aft makes the airplane less stable—maybe even totally uncontrollable. Just because an airplane has six seats doesn’t mean all those seats can accommodate FAA-standard 170-pound passengers, and just because there’s space left in the baggage compartment doesn’t mean it can be filled.

“Pump the throttle to help start the engine.” Pumping the throttle works fine in priming automobile engines because their induction systems are downdraft: The carburetors are on top, and the excess fuel the accelerator pump squirts into the carburetor flows down into the engine. Most aircraft engines are updraft, with the carburetors mounted upside down on the bottom of the engine, so the raw fuel pumped in drips down into the air induction system, setting the stage for an induction fire.

“Use more speed in a crosswind.” All that speed does in a crosswind is give the wind more time to bedevil the pilot while floating down the runway. If there is a high gust spread, add half the amount of the gust spread, but there will still be excess float. If it’s a tailwheel airplane, a wheel landing may be performed at a higher-than-normal speed. It can be nailed on rather than being hoisted or dropped by the gusts as it could be in a full-stall, three-point landing. This is the sole purpose of a wheel landing on a taildragger. (Let the email rebuttals begin.)

“Tailwheel aircraft are dangerous.” It’s a good thing we didn’t know tailwheels were dangerous for the first 50 years of aviation. A taildragger does require more refined, specialized pilot technique, but that can be learned in five hours of flight training, give or take an hour or two, and is well worth the effort.

“Crosswinds are dangerous.” Avoiding crosswinds means a pilot won’t get to fly very often. Crosswinds are a part of nature and something to be understood and conquered, not avoided. They aren’t the boogeyman under the bed—and a few hours of specialized training will prove that.

“Runways less than 2,000 feet long are dangerous.” “Dangerous” is a term pilots use when they are out of their comfort zone. The length of pavement required to safely land light general aviation airplanes, from a Cessna 152 to a Beechcraft Bonanza—as shown in their pilot’s operating handbooks—ranges from under 500 feet to 962 feet at gross weight and sea level. What makes a runway short is the amount of runway left behind on touchdown, then the approach, the density altitude, the amount of wind on the nose, and, finally, the runway surface. A 2,000-foot, undulating grass runway cut into the trees in Colorado is a challenge. A 2,000-foot paved one in New Jersey with decent approaches is a piece of cake.

“Charts aren’t needed when flying GPS.” A chart, a pencil, and the compass don’t require batteries. And even if angry aliens knock every satellite out of the sky, charts and a compass will still work. The smart money keeps a thumb on a sectional and notices the compass heading.

“GPS is a lifesaver.” Sometimes yes, sometimes no. Counting on the “nearest airport” button to get out of bad weather can convince you to fly farther into weather, when a quick one-eighty is the proper maneuver.

“Advancing age is a reason to stop flying.” Age has little to do with the ability to fly. It does require some surplus cash and sometimes that’s a function of age, but it’s not necessarily a young person’s game. Plus, the physical demands are low. Age can’t extinguish the aviation passion unless we let it.

“Flying low is OK if in a slow airplane.” Is hedge hopping OK in a slow airplane? A hedge really doesn’t care how slow you’re moving when you hit it. Ditto a power line, a TV tower, a cell tower, or the tall tree in your buddy’s front yard. Not to mention, if you lose an engine when low, your choices of what to do and where to go are next to zero. Altitude is safety.

“Engines almost never quit.” The operative word in that sentence is “almost.” How many engine failures is enough? One is too many. The specter of losing the engine should constantly haunt a pilot to the point he or she always has a field picked out while in the air. The instant an engine quits, your brain will cease to function normally, so every decision to be made must have already been made.

“Fuel gauges are always pessimistic.” Some sort of twisted thinking says that when a fuel gauge is on empty, there’s always enough left to get you to an airport. That is wrong. For one thing, the fuel in most fuel tanks is almost never totally available. There’s almost always a gallon or two that won’t feed. Plus, the accuracy of fuel gauges is not to be trusted. So many accidents are the result of someone looking at a fuel gauge and saying, “We probably have enough.” Words like “probably” shouldn’t be uttered in the confines of a cockpit.

“A little prop nick is no big deal.” Wrong. Any scratch you can feel with your fingernail is at least 0.003 inches deep. At the sharp bottom of that scratch, the stress in the local area is concentrated many times over. On top of that, if it’s a nick in the propeller, that represents a pretty serious stress riser—and fatigue loves stress risers. Especially in aluminum. There’s nothing like vibration or pulsating loads to find that stress riser and turn it into a fatigue crack. Lose a chunk of the prop and it’s possible for the vibration to be so fierce that it tears the engine off the airplane. If a nick is found on the prop, ground the airplane until your local airplane and powerplant mechanic files it out.

“Even on a sloped runway, land into the wind.” Yes, we make a point to land into the wind. However, sometimes the slope on a major runway is such that landing downslope requires a significant headwind to counteract the effect of the slope. Landing uphill with a slight tailwind seems counterintuitive, but in some situations it is required.

“Density altitude is no big deal.” Boy, is that wrong—especially in parts of the country where temperatures and topography combine to suck the life out of an airplane. And you don’t have to be in Denver to experience the effects. At 80 degrees Fahrenheit, a runway that is 1,500 feet above mean sea level (msl) becomes nearly 2,900 feet above sea level; 90 degrees makes it 3,500 feet and 100 degrees shoves it up to 4,100 feet. Those density altitudes represent big drops in available power and aerodynamic efficiency, and your usually spritely little performer turns into a real dog and can’t get out of its own way.

“Don’t believe placards: They have a lot of margin built into them.” In some cases they do. However, there’s no way to know how much the margin is without knowing the engineering assumptions behind them. They might be based on structural concerns. In other words, believe what the placard says and behave accordingly.

“A really low-time engine makes an airplane worth more.” It’s hard to tell how many people have bought an airplane with a 200-hour engine on it, only to have it start grinding itself to death in a few hours. The villain isn’t the number of hours, but how long ago it was rebuilt and whether the airplane sat dormant for an extended period—and, equally important, where it was located during its extended slumber. Lycomings, for instance, hate not being used. Their camshaft often begins to rust. If the airplane is near water or industrial smog, the process is accelerated. Plus, the time on an engine doesn’t say who rebuilt it and to what specifications it was overhauled or rebuilt—both words that have specific meanings to the FAA.

“Fixer-upper airplanes are great bargains.” Unless you’re capable of doing the paint, engine work, and avionics upgrades yourself, you won’t save money this way. It might work on a few airplanes, but the vast majority of the time it’s better to buy the best airplane in the class. A DIY dream could turn into a nightmare.

In conclusion

We haven’t even scratched the surface of the myths hidden within aviation. So, don’t take everything you’re told on face value. Do a little research and find the truth for yourself. That’s what aviating is all about.