A Calculation Method of Elevator Preset Deflection for Aircraft Takeoff

Abstract

The invention discloses a method for calculating preset skewness of an elevator at taking-off time of an airplane. The method comprises: step one, a taking-off longitudinal control force design speed point of an airplane at a take-off stage is determined; step two, a weight is selected, and an elevator skewness value (delta e front) of a gravity center front limit at the design speed point as well an elevator skewness value (delta e rear)of a gravity center rear limit at the design speed point under the weight is calculated; step three, the delta e front and the delta e rear are divided by an elevator transmission ratio k1 to obtain corresponding longitudinal control displacement values, and then a longitudinal control force corresponding to the gravity center front limit and a longitudinal control force corresponding to the gravity center rear limit are calculated; step four, an F target is taken, wherein the F target meets a formula: F target=Fe1+Fe2) / 2; and whether an absolute value of the F target meets a specification requirement is checked; and step five, taking-off elevator preset skewness values at different gravity centers are obtained. According to the invention, corresponding elevator preset skewness values are set based on gravity center changing situations of different flying tasks, so that the longitudinal control force meets the specification requirement when the airplane takes off.

Description

technical field [0001] The invention relates to the technical field of aircraft maneuverability stability design, in particular to a method for calculating the preset deflection of an aircraft take-off elevator. Background technique [0002] There are many types of aircraft flight missions, resulting in drastic changes in the center of gravity of the aircraft when performing different flight missions, and large changes in the longitudinal control force during takeoff. The national standard stipulates that the longitudinal control force required for takeoff should be between 230N pull rod force and 90N push rod force. For some flight tasks, the longitudinal control force may not meet the requirements when the aircraft takes off, and in different flight tasks, due to the different center of gravity, the longitudinal control force changes drastically during take-off, which not only increases the pilot's control burden, but also brings certain Security risks! These problems ca...

AI Technical Summary

Problems solved by technology

[0003] The existing technology can make the take-off longitudinal control force meet the specification requirements by setting the adjustable horizontal stabilizer and presetting the deflection of the take-off horizontal stabilizer. However, the setting of the adjustable horizontal stabilizer not only increases the structural weight of the aircraft, but also increases the system design difficulty

[0004] And on some fixed horizontal stabilizer aircraft, the above-mentioned prior art cannot be used

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