GB699991A - Helicopter aircraft landing gear - Google Patents

Abstract

699,991. Helicopter undercarriages. BELL AIRCRAFT CORPORATION. Oct. 8, 1951. No. 23410/51. Class 4. An undercarriage for a helicopter comprises landing skids extending fore and aft of the centre of gravity of the aircraft one at each side below the aircraft structure and rigidly suspended from the outwardly projecting ends of abeam structure extending transversely of the aircraft structure and rigidly connected intermediate its ends to the aircraft structure, said beam structure being the sole means of connection between the and the aircraft structure and being so constituted as to absorb by distortion or deflection the landing loads transmitted thereto from the skids. The undercarriage comprises a pair of skids 22 formed with rigid upwardly extending legs 18 each attached to the extremity of a resilient transverse tubular beam 14 fast with the aircraft structure 2. Each skid carries a wheel 25 pivotally attached thereto below the centre of gravity 40 of the aircraft by a cranked axle 26 which may be moved by manual operation from the position shown where the wheel lies above the lower surface of the skid to a lower position to enable the aircraft to be wheeled. The skids extend a greater distance forward of the centre of gravity 40 than they extend aft thereof and a number of different sections and stiffness criteria are given for the beams 14 which are intended to deflect within their elastic range during a normal landing but to be permanently deflected beyond their elastic limit by a crash landing.