Patent ID: 7429019

Claim:
A steerable auxiliary nose undercarriage for a rotary wing aircraft, the undercarriage being retractable substantially rearwards and comprising at least: a wheel set having a wheel axle about which at least one wheel rotates; a generally longitudinally-extending oscillating system having a first end supporting the wheel axle, and a hinged front end that is longitudinally opposite from the first end, the oscillating system being pivotally mounted via at least one transverse hinge for anchoring to a force-transmission structure for being rigidly secured to the aircraft, and the wheel axle being arranged on the oscillating system via a steering pivot wherein the oscillating system extends substantially in a longitudinal X-direction while in the fully extending position; and a shock-absorbing actuator having a connection end hinged to the oscillating system, the shock-absorbing actuator having a coupling end axially opposite from the connection end, the coupling end being hinged to the structure, the oscillating system presenting an elevation stroke about its hinged front end that is greater than a shock-absorbing stroke; wherein: said steering pivot comprises a steering axis substantially intersecting the wheel axle, said steering pivot enabling the wheel to be steered on either side of a position corresponding to the aircraft running in a straight line, a steering actuator being substantially integrated about said steering axis so that said steering axis extends through said steering actuator; the shock-absorbing actuator extends substantially in the longitudinal direction and possesses means for retracting the oscillating system beyond an abutment position marking the end of the shock-absorbing stroke, so that the oscillating system and the shock-absorbing actuator perform both a function of absorbing shocks and a function of retracting the undercarriage; and said coupling end is hinged to a reinforced structural bottom floor of the structure, while said connection end is connected to a crank fitting of the oscillating system.