PFR - Aerospace Engineering Sciences Senior Design Projects ...

Project Final Report – CUDBF April 30 th , 2009
ASEN 4028: Aerospace Senior Projects
Mission 1, where two laps will be timed for the score and in Mission 3 where flight endurance is
crucial.
The three landing gear configurations considered for the design included tricycle, bicycle, and
tail-dragger style landing gear and are shown in Figure 28. A tricycle configuration has one nose
gear and two wheels on a main gear just aft of the aircraft center of gravity. A bicycle
configuration has one nose gear and one nose wheel inline on the centerline of aircraft, and
sometimes employs wing-tip outriggers for lateral balance. The tail-dragger configuration is
similar to an inverted tricycle gear, where a tail gear is used and the two wheels on the main gear
are just forward of the aircraft center of gravity.
Figure 28: Landing Gear Configuration Options
After examining the three landing gear configuration’s characteristics in each of the four main
parameters, the tricycle configuration was determined to be the best all around performer. The
tricycle configuration is widely regarded as the most ground stable due to the aircraft center of
gravity’s location just forward of the main gear. The tricycle configuration is not as vulnerable
to tip over from take-off side gusts. Tail-dragger and bicycle configurations are vulnerable since
they must pivot about one wheel. Ground authority on a tricycle landing gear is simpler than the
tail-dragger which has nose over and ground loop issues. The tricycle gear’s ground stability
also outperforms the bicycle gear which must balance on the center-line mounted landing gear.
The bicycle gear is also particularly vulnerable to tip over with the large expected lateral CG
shifts. The tricycle gear is the only one of the three that has the capability to rotate during the
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