Ask Pete!

by Pete Schoeninger

Q: Why do airliners usually NOT lower one wing (slip) into a crosswind when landing like light planes do? It seems they often touch down wings about level, but in a crab (sideways.) Their tires must take a terrible beating?

A: Some airliners have two or four engines hung under the wings. If a wing was lowered into a crosswind, it is very possible an engine would strike the ground. Tires are expensive, but engines cost lots more!

Q: An old timer told me that I should ALWAYS fill my fuel tanks at the end of day, to prevent condensation forming while in storage, and turning into water. Is that really true?

A: In the post World War II days, lots of training was done with airplanes, such as Piper J-3 Cubs, with small gas tanks and no readily accessible fuel drain. Those airplanes usually had one 12-gallon nose tank that provided a last drop range of about 3 hours. Keeping those tanks full when possible reduced the possibility of condensation (water) on fuel tank walls. Modern airplanes offer fuel tank drains and lots more fuel capacity, allowing a pilot to choose between lots of gas for a long flight, or more cabin capacity (people, baggage, etc.), but not both. If a person follows the manufacturer’s recommendations for fuel draining and sampling, you should be okay. Many Cessna 172RGs have 6.0 hours of fuel capacity, and some Piper Cherokees have 5.5 hours of fuel capacity. A friend of mine owns a Cessna 421C, which can carry up to 1600 lbs of fuel (useful load is 2100 lbs, leaving him only 500 lbs in the cabin with all tanks full.) If you constantly carry full fuel in these and other airplanes, you are limiting your cabin load, and hurting performance dragging around unneeded fuel much of the time. The other reason to top off your tanks in aircraft, such as Cessnas that have “fuel bladders,” is to keep the bladders moist and flexible, rather than dry and brittle that will reduce their life span.

Q: Recently, I saw a guy get a jumper cable start from a truck in his Piper Arrow, and then he took off on a long IFR night flight. The lineman who jumpstarted the aircraft told me the pilot admitted he had left the master switch on after a previous flight, and the battery had drained down to nothing. Was immediately taking off a wise decision on the part of the pilot?

A: NO! Right after engine start from the jumpstart, the alternator probably was providing enough electrical power to run radios, lights, etc., but if the alternator conked out, there would be almost no reserve power in the battery to navigate to a suitable airport, power the landing light, etc. A safer course of action would be to remove the battery from the airplane and place it on a suitable charger until fully charged (it can take many hours to completely recharge a dead aircraft battery). My advice is to take the time and do it right.

EDITOR’S NOTE: Pete Schoeninger is an aviation consultant and aircraft appraiser who lives in Wisconsin. He is an experienced fixed base operator, aircraft salesman and airport manager. Email your questions about all things aviation to: Pete.Harriet@gmail.com. For assistance with aircraft appraisals or fixed base operator and airport management consultation, call 262-533-3056. Any answers provided in this column are the opinion of the author and not this publication, or its editor, publisher, owners and affiliates.

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