F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
F16F9/06—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium using both gas and liquid
B—PERFORMING OPERATIONS; TRANSPORTING
B64—AIRCRAFT; AVIATION; COSMONAUTICS
B64C—AEROPLANES; HELICOPTERS
B64C25/00—Alighting gear
B64C25/32—Alighting gear characterised by elements which contact the ground or similar surface
B64C25/58—Arrangements or adaptations of shock-absorbers or springs