Being able to make a trip nonstop is more than just convenience—it can be a safety of flight issue as the risk of an accident is highest during takeoff and landing. The reality is that most flights of four- and six-place airplanes are conducted with only one or two of the seats occupied and at something below gross weight. For many owners, that means that some sort of auxiliary fuel tanks can give their airplanes more range and potentially increase safety.
We surveyed the six major companies that provide aux fuel tanks and found that they weren’t as expensive as we expected, and there are some that can tack on at least two hours of fuel for a large proportion of the general aviation fleet. While every mod involves tradeoffs, the penalties in terms of drag and weight seem to be minor and the benefits—including, in some cases, gross weight increases—can be quite nice.