民用运输类飞机最小离地速度试飞风险控制

对于民用运输类飞机,最小离地速度是制定飞机起飞特征速度的关键,是保障飞机安全起飞离地的基础速度,必须通过飞行试验确定飞机的最小离地速度,并演示飞机在该速度下能够安全地起飞离地。由于进行最小离地速度试验时,飞机是在一种大迎角状态下起飞,加之地面效应的影响,飞机离地后极易触发失速告警,甚至进入失速状态。对于受几何结构限制的飞机,在地面保持大姿态滑跑时,由于规章有擦地时间的要求,因此对试飞员的驾驶技术要求极高,一旦操作不当,可能造成飞机结构的损伤。文章研究了最小离地速度试飞的风险点,制定了飞机结构保护措施和试飞驾驶技术,在研的运输类飞机最小离地速度合格审定飞行试验可参考使用。

For the civil transport aircraft, the minimum unstick speed （Vmu） is the key to determining the take-off characteristicvelocity and the basic speed for the safe take-off of the aircraft. The minimum unstick speed of the aircraft must be determinedthrough flight tests, and demonstrates that the plane can safely take off from the ground at this speed. Due to the fact that the air-craft takes off at a high angle of attack and the impact of ground effect, it is easy to trigger the stall alarm and even enter the stallstate when the Vmu test is carried out. For the aircraft restricted by geometric structure, when the plane glides in a large attitude onthe ground, the rules and regulations require the time to wipe the ground, so the driving technology of the test pilot is very high;once the operation is improper, it may cause damage to the aircraft structure. In this paper, the risk point of the flight test at theminimum unstick speed is studied, and the structure protection measures and flight test technology of the aircraft are established,which can be used for reference in the approved flight test of the transport aircraft at the minimum unstick speed.