Few aircraft are designed with tandem landing gear. As the
name implies, this type of landing gear has the main gear
and tail gear aligned on the longitudinal axis of the aircraft.
Sailplanes commonly use tandem gear, although many only
have one actual gear forward on the fuselage with a skid
under the tail. A few military bombers, such as the B-47 and
the B-52, have tandem gear, as does the U2 spy plane. The
VTOL Harrier has tandem gear but uses small outrigger gear
under the wings for support. Generally, placing the gear only
under the fuselage facilitates the use of very flexible wings.