АЛГОРИТМ РОЗРАХУНКУ ДИСТАНЦІЇ ПЕРЕРВАНОГО ЗЛЬОТУ В РЕЖИМІ РЕАЛЬНОГО ЧАСУ

• Datum: 2020
• Hauptverfasser: Belousov, A.A., Kuleshyn, V.V., Vyshenskiy, V.I.
• Format: Artikel
• Sprache: English
• Veröffentlicht: V.M. Glushkov Institute of Cybernetics of NAS of Ukraine 2020
• Schlagworte: перерваний зліт; довжина ділянки гальмування; алгоритм у реальному часі; рівняння Ріккаті
• Online Zugang: https://jais.net.ua/index.php/files/article/view/458
• Назва журналу: Problems of Control and Informatics

A rejected takeoff or aborted takeoff is the situation in which it is decided to abort the takeoff of an airplane. When an aircraft crew needs to take a «go – no go» decision, they compare the current speed with the «takeoff decision speed». Based on this speed, it is possible to estimate if the aircraft can stop safely within the AccelerateStop Distance Available. These values are taken from the aircraft flight manual before the takeoff. The accident analyses show that if the current speed is near the «takeoff decision speed», the real Accelerate-Stop Distance can be different from the value calculated in advance. Accelerate-Stop Distance can be underestimated, that leads to overrun after taking «no go» decision. It can be also overestimated, that prevents the crew from choosing «no go» decision though it is still safe. The proposed real-time algorithm for calculation of the Accelerate-Stop Distance uses step interpolation of the jet thrust. The two thrust change intervals (thrust decreases from maximum to zero and then increases to the nominal reversal thrust) can be interpolated by three intervals of constant thrust (maximum forward thrust, zero thrust, nominal thrust reversal). With this interpolation, the Riccati equation of the aircraft motion has three different solutions, corresponding to three different constant thrusts. This approach allows to obtain the explicit solutions of the aircraft motion equations. It is possible to use these solutions in real-time calculations. The algorithm takes into account various aircraft parameters (velocity, thrust, etc.) before the moment of the decision. As a result, the Accelerate-Stop Distance can be evaluated more accurately comparing with pre-calculated value. It is especially important if the aircraft speed is close to the «takeoff decision speed». In this situation, the aircraft crew obtains more accurate information about Accelerate-Stop Distance, and avoid the overrun during rejected takeoff. So the «go – no go» decision will be more reliable and safe.