Cargo aircraft

A cargo aircraft is an airplane designed and used for the carriage of goods, rather than passengers. This role demands a number of features that makes a cargo aircraft instantly identifiable; a "fat" looking fuselage, a high-wing to allow the cargo area to sit near the ground, a large number of wheels to allow it to land at unprepared locations, and a high-mounted tail to allow cargo to be driven directly into and off the aircraft. The cargo class should be compared to the freight aircraft, which is a conversion of an existing passenger design, which lacks most of these "custom" features.
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An aircraft that is used to transport cargo and is not engaged in carrying passengers. The terms cargo aircraft only, cargo-only aircraft and cargo aircraft have the same meaning. (49CFR171)