Autorecovery system from dangerous height with prognosis of height of completion recovery maneuver

Aviation technologies


Evdokimchik E. A.

Russian Aircraft Corporation «MiG», 7, 1st Botkinsky passage, Moscow, 125284, Russia



When the pilot flies at medium and low altitudes in adverse weather conditions, he can make downward maneuver that cannot be completed without crossing a dangerous height (dangerous height is height below which the collision with obstacles is very probable). Necessity for monitoring of dangerous height increases the load on the pilot and diverts him from performing a specific task. So the efficiency of implemented task is reducing.

The object of article is to create an autorecovery system, which would allow to fly without focusing attention on the control of dangerous height.

At the present time there are the ground collision systems based on the prediction of the aircraft trajectory and the formation of a safe corridor. Using these systems for highly maneuverable aircraft is limited because of their ability to perform intensive and low predictable maneuvers. Also, there are the ground collision systems based on calculation of a altitude which is lost during the execution automatic recovery maneuver. This height is calculated as a function of the motion parameters. The disadvantage of these systems is that the loss of height is determined at the time of inclusion of the automatic recovery and not taken into account changes in the permissible and available g-loads that may occur during the recovery maneuver. Some algorithms do not use the maximum possible g-load on current fly mode. As a result, the area in which the «Recovery» mode intervene in the control of the aircraft increases.

The paper proposes a system based on integration of simplified differential equations of aircraft motion. The system consists of trajectory and velocity prediction block, model of pilot actions, and the aircraft model. This approach makes it possible to predict the height of the completion of the recovery maneuver and other aircraft motion parameters. These parameters are taken into account in determining the permissible and available g-loads during the recovery maneuver, which increases the accuracy of the system. A command occurs when the height of completion recovery maneuver is equal to dangerous height. Recovery maneuver consists of a roll to wings level combined with a pull up at 5g or the maximum available.

Result of the work is improving the safety near the ground. As a result of the paper the parameters of the proposed system for the MiG-29 K(KUB) is defined. A mathematical modeling has showed the acceptable performance of the system.


autorecovery system from dangerous height, prognosis of height , of completion recovery maneuver


  1. Baburov V.I., Volchok J.G., Gal’perinT.B., Gubkin S.V., Maslov A.V., Sauta O.I. Patent RU 2376645 С1, 20.12.2009.
  2. Bushe K., Demort’e Z. Patent RU 2375757 С2, 10.12.2009.
  3. Gregory W. Bice, Mark A. Skoog, John D. Howard. Patent US 4924401, 08.05.1990.
  4. Koziorov L.M., Lerner I.I. Patent RU 2368954 С2, 27.09.2008.
  5. Lebedev A.A., Chernobrovkin L.C. Dinamika poleta bespilotnykh letatel’nikh apparatov (Flight dynamics of pilotless flight vehicles), Moscow, Mashinostroenie, 1973, 616 p.

Download — informational site MAI

Copyright © 2000-2021 by MAI