A study was performed to characterize an optimum return trajectory for a sailplane after a rope-break failure during an aerotow launch procedure. The performance of an SGS 1-26E sailplane was simulated using the equations of motion for quasi-steady flight in a time-stepping routine and published aerodynamic polar data. A gradient-based optimization algorithm was implemented using the simulated trajectory considering the glide velocity, bank angles, and runway offset angle to determine the minimum rope-break altitude from which a successful return could be theoretically produced. The SGS 1-26E sailplane was used in a flight-test campaign for empirical turn modeling and validation of the performance simulation. The minimum altitude where a return trajectory and downwind runway landing could be successfully completed after a rope-break event was observed to be 76.4 ft above ground level. A headwind and crosswind presence was observed to decrease the minimum rope-break altitude with increasing wind velocity up to a critical value, after which rope-break altitudes began to increase. These minimum rope-break altitudes serve as a theoretical indication that safe trajectories can be performed at lower failure altitudes than the commonly practiced decision altitude of 200 ft for certain wind conditions.

进行了一项研究，以表征滑翔机在起飞过程中绳索断裂失败后的最佳返回轨迹。SGS 1-26E 滑翔机的性能使用时间步进例程中准稳态飞行的运动方程和已发布的空气动力学极地数据进行模拟。使用考虑滑行速度、坡度角和跑道偏移角的模拟轨迹实施基于梯度的优化算法，以确定理论上可以产生成功返回的最小断绳高度。SGS 1-26E 滑翔机用于飞行试验活动，用于经验转弯建模和性能模拟验证。观察到绳索断裂事件后返回轨迹和顺风跑道着陆可以成功完成的最低高度为离地 76.4 英尺。观察到逆风和侧风的存在会随着风速增加到临界值而降低最小断绳高度，此后断绳高度开始增加。这些最小断绳高度作为一个理论指示，表明安全轨迹可以在比通常实践的 200 英尺决断高度更低的故障高度下执行，对于某些风力条件。