초록 ▼

Wind tunnel data for a three control surface aircraft is developed for lift, pitching moment, and drag coefficient characteristics. This data is then input into a Lagrange optimization program to determine a unique combination of canard, flap, and strake flap position that trimmed the pitching momen

Wind tunnel data for a three control surface aircraft is developed for lift, pitching moment, and drag coefficient characteristics. This data is then input into a Lagrange optimization program to determine a unique combination of canard, flap, and strake flap position that trimmed the pitching moment coefficient to zero and provided the minimum drag coefficient as a function of lift coefficient and/or angle of attack, Mach number, and altitude. This program is exercised over the entire Mach number, altitude, and angle of attack range of the aircraft. The output from the Lagrange optimization program are then tabulated and loaded into the memory of a digital flight control computer of an aircraft. As the aircraft flies, the angle of attack sensor, air data sensor and altimeter determine the angle of attack, Mach number and altitude of the aircraft. By means of the computer, the position of the control surfaces are changed to the predetermined settings of the look-up table for minimum drag.

대표청구항 ▼

In a mulitiplane aircraft having a plurality of control surfaces and provided with means for sensing angle of attack, Mach number, altitude and pitch rate, an automatic camber control system comprising: a computer having storing means for storing a look-up table containing pre-established angular po

In a mulitiplane aircraft having a plurality of control surfaces and provided with means for sensing angle of attack, Mach number, altitude and pitch rate, an automatic camber control system comprising: a computer having storing means for storing a look-up table containing pre-established angular position data for each of the control surfaces which achieve mimimum drag and zero pitching moment for corresponding sensed angle of attack, Mach number and altitude; actuating means connected between the computer and each of the control surfaces for deflecting each control surface to the pre-established angular positions after a non-zero pitching moment is found to exist for the aircraft; and means connecting the pitch rate sensing means to the computer for initiating a new cycle of control surface operation each time the pitch rate sensing means signifies the occurrence of a non-zero pitching moment on the aircraft.