民用飞机控制律对偏航机动载荷影响分析

飞机机动过程中方向舵快速大幅偏转会使方向舵和垂尾上产生较大气动载荷并传递到后机身,导致 驾驶员来回往复蹬舵造成安全事故。针对 CCAR-25部25.351条规定的偏航机动情况及 CS-25部25.353规定的偏航机动新条款——方向舵往复偏转,本文首先对两种偏航机动条款分别进行分析;然后考虑控制律进行 偏航机动情况机动仿真计算;最后通过比较分析飞机响应运动参数及垂尾载荷计算结果,并分析控制律对偏航 机动载荷的影响。结果表明:对于偏航机动,考虑控制律后飞机的响应幅度有所缓减,导致垂尾载荷有所降低; 对于偏航机动新条款,由于方向舵反向偏转导致侧滑角贡献和方向舵偏度贡献垂尾载荷两者叠加,从而导致垂 尾载荷大幅增加;P-Beta控制律有效降低了方向舵往复偏转的垂尾载荷。

Influence of Control Law on Yaw Maneuver Load about Civil Aircraft

Based on yaw maneuver situation stipulated in article 25.351 of CCAR-25 and rudder control reversal situation stipulated in article 25.353 of CS-25, this paper firstly makes an understanding of article CCAR25.331 and CS25.353, then carries out maneuver simulation calculation for two yaw maneuver situations with/without the consideration of control law respectively, and finally makes a comparative analysis of the aircraft response and the vertical-tail load. The results of calculation and analysis show that: 1) for the yaw maneuver situation, the response attitude of the aircraft is reduced after considering the control law, and the vertical-tail load is reduced; 2) after considering the rudder control reversal, the response attitude of the aircraft and beta are increased, and the vertical-tail load is finally increased;3) the vertical-tail load caused by the rudder control reversal can effectively be reduced after considering the P-Beta control law.