Optimal paths through downbursts
Optimal paths through downbursts
复制标题
通过下击暴流的最佳路径
DOI：
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发表时间：
1989
期刊：
影响因子：
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通讯作者：
A. Bryson
中科院分区：
文献类型：
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作者：
Yiyuan J. Zhao;A. Bryson
对飞机的下突飞行控制是一个具有最小高度约束和两种不同性能指标的动态优化问题。主要考虑起飞飞行，讨论着陆飞行。路径是通过风切变和下气流来确定的，(1)最大化穿透后的空速和高度的组合，(2)最小化与预定飞行路径的偏差。(1)可以被认为是一种“生存”措施，(2)可以被认为是一种“保持性能”措施。对于轻度至中度下爆，性能策略以空速损失为代价保持高度，而生存策略将飞机下降到最小高度以获得更多空速。对于严重的下爆，两条最高路径是相似的，大部分时间都在最低高度。换句话说，飞机必须在剧烈的下爆中下降才能生存。由于下爆的强度很难评估，我们建议当飞行员认为他已经进入下爆时使用生存飞行路径策略。这种策略包括立即使用最大推力，同时快速下降
The control of an aircraft flying through a downburst is formulated as a dynamic optimization problem with a minimum altitude constraint and two different performance measures. Take-off flight is mainly considered while landing flight is discussed. Paths are determined through windshears and downdrafts that (1) maximize a combination of airspeed and altitude just after penetration and (2) minimize deviation from the intended flight path. (1) may be thought of as a "survival" measure and (2) as a "performancemaintaining" measure. For mild to moderate downbursts, the performance strategy maintains altitude at the expense of airspeed loss, while the survival strategy descends the aircraft to the minimum altitude to obtain more airspeed. For a severe downburst, the two op timal paths are similar, spending most of the time at the minimum altitude. In other words, the aircraft has to descend in a severe downburst to survive. Since the intensity of a downburst is difficult to assess, we recommend use of the survival flight path strategy when the pilot believes that he has entered a downburst. This strategy involves immediate application of maximum thrust, along with rapid descent