System and method to assist in the braking of an aircraft on a landing runway

Abstract

The system comprises a means of acquiring the position of the aircraft on the runway and its speed in the taxiing phase, a means of storing data concerning the runway and a predefined deceleration law, a function for calculating the distance that the aircraft will have traveled on the runway when it has reached a certain speed and/or the speed that it will have reached when it has traveled a certain distance: the calculated distance makes it possible to adapt the braking by comparison with the distance remaining to reach the end of the runway; the calculated distance makes it possible to adapt the braking by comparison with the distance remaining to reach the end of the runway; the calculated speed makes it possible to adapt the braking by comparison with the maximum speed to take the exit.

1 . A method to assist in adjusting the braking intensity of an aircraft on a landing runway comprising the steps of:
 recovering data concerning the aircraft or concerning the runway where the aircraft is landing;   acquiring the position of the aircraft on the runway and its speed in the taxiing phase;   calculating the distance that the aircraft will have traveled on the runway when the aircraft has reached a certain speed and/or the speed that it will have reached when the aircraft has traveled a certain distance, the distance and/or the speed being calculated assuming that the speed of the aircraft decreases according to a predefined time function;   wherein the limitation of the difference between the calculated distance and a determined distance and/or between the calculated speed and a determined speed allows the braking intensity to be increased or reduced.   
   
   
       2 . The method to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 1 , wherein the position characterizing the start or the end of the runway and the length of the runway are recovered in the data recovery phase and the distance that the aircraft will have traveled on the runway when it has reached a zero speed is calculated in the calculation phase, the limitation of the difference between the calculated distance and the distance remaining to reach the end of the runway allowing the braking intensity to be increased or reduced. 
   
   
       3 . The method to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 1 , wherein the position characterizing the start or the end of the runway, the length of the runway and the controlled speed of the aircraft below which the aircraft can perform any turn maneuver when taxiing are recovered in the data recovery phase and the distance that the aircraft will have traveled on the runway when the aircraft has reached its controlled speed is calculated in the calculation phase, the limitation of the difference between the calculated distance and the distance remaining to reach the end of the runway allowing the braking intensity to be increased or reduced. 
   
   
       4 . The method to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 1 , wherein the position characterizing a runway exit and the maximum speed to take this exit are recovered in the data recovery phase and the speed that the aircraft will have reached on the runway when it has traveled the distance to the exit is calculated in the calculation phase, the limitation of the difference between the calculated speed and the maximum speed to take the exit allowing the braking intensity to be increased or reduced. 
   
   
       5 . The method to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 1 , wherein the position characterizing a runway exit and the angle that this exit makes with the axis of the runway are recovered in the data recovery phase, this angle making it possible to deduce a maximum speed to take this exit, and the speed that the aircraft will have reached on the runway when the aircraft has traveled the distance to the exit is calculated in the calculation phase, the limitation of the difference between the calculated speed and the maximum speed to take the exit allowing the braking intensity to be increased or reduced. 
   
   
       6 . The method to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 1 , wherein the distance and/or the speed are calculated assuming that the speed of the aircraft decreases according to a time-dependent function only. 
   
   
       7 . The method to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 6 , wherein the distance and/or the speed are calculated assuming that the speed of the aircraft decreases according to a linear time function. 
   
   
       8 . The method to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 1 , wherein the distance and/or the speed are calculated assuming that the speed of the aircraft decreases according to a function depending on time and on other variables characterizing the instantaneous braking quality given the state of the runway or of the aircraft and being estimated when taxiing on this runway. 
   
   
       9 . The method to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 1 , wherein the distance and/or the speed are calculated by taking into account only the speed component along the axis of the runway. 
   
   
       10 . The method to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 9 , wherein the axis of the runway is determined by extraction from an airport database containing the position of the thresholds and of the ends of the runway or containing the geographic orientation of the runway. 
   
   
       11 . The method to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 9 , wherein the axis of the runway is obtained by calculation based on the coordinates of notable points of the runway on which the aircraft is, such as the thresholds or the ends of the runway obtained from an airport database. 
   
   
       12 . The method to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 9 , wherein the axis of the runway is supplied by on-board systems. 
   
   
       13 . A system to assist in adjusting the braking intensity of an aircraft on a landing runway comprising:
 a means of acquiring the position of the aircraft on the runway and its speed in the taxiing phase;   a means of storing data concerning the runway where the aircraft is landing and a predefined deceleration law;   a function for calculating the distance that the aircraft will have traveled on the runway when it has reached a certain speed and/or the speed that it will have reached when it has traveled a certain distance, the distance and/or the speed being calculated assuming that the speed of the aircraft decreases according to the deceleration law;   the limitation of the difference between the calculated distance and a determined distance and/or between the calculated speed and a determined speed allowing the braking intensity to be increased or reduced.   
   
   
       14 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 13 , wherein the position characterizing a runway start or end point and the length of the runway are stored in the storage means and the distance to be traveled by the aircraft to reach a zero speed is calculated by the calculation function, the limitation of the difference between the calculated distance and the distance remaining to reach the end of the runway allowing the braking intensity to be increased or reduced. 
   
   
       15 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 13 , wherein the position characterizing a runway start or end point, the length of the runway and the controlled speed of the aircraft below which the aircraft can perform any turn maneuver when taxiing are stored in the storage means and the distance to be traveled by the aircraft to reach the controlled speed is calculated by the calculation function, the limitation of the difference between the calculated distance and the distance remaining to reach the end of the runway allowing the braking intensity to be increased or reduced. 
   
   
       16 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 13 , wherein the position of the point characterizing a runway exit and the maximum speed to take this exit are stored in the storage means and the speed that the aircraft will have reached on the runway when it has traveled the distance to the exit is calculated by the calculation function, the limitation of the difference between the calculated speed and the maximum speed to take the exit allowing the braking intensity to be increased or reduced. 
   
   
       17 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 14 , comprising an automatic braking module allowing the braking intensity to be increased or reduced by limitation of the difference between the stopping distance or the distance to reach the controlled speed of the aircraft and the distance remaining to reach the end of the runway or by limitation of the difference between the speeds at the exits and the maximum speeds to take the exits. 
   
   
       18 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 14 , comprising an audible alert module raising an alert if the stopping distance or the distance to reach the controlled speed of the aircraft is greater than the distance remaining to reach the end of the runway or if no exit can be reached at a speed less than or equal to its maximum exit speed. 
   
   
       19 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 14 , comprising a visual alert module raising an alert if the stopping distance or the distance to reach the controlled speed of the aircraft is greater than the distance remaining to reach the end of the runway or if no exit can be reached at a speed less than or equal to its maximum exit speed. 
   
   
       20 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 14 , comprising a module displaying the stopping distance or displaying the distance to reach the controlled speed or displaying the speeds at the exits. 
   
   
       21 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 20 , wherein the current position of the aircraft on the runway is graphically represented. 
   
   
       22 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 20 , wherein the stopping distance or the distance to reach the controlled speed of the aircraft is graphically represented. 
   
   
       23 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 20 , wherein the tendency to shorten or lengthen the stopping distance or the distance to reach the controlled speed of the aircraft is graphically displayed. 
   
   
       24 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in one of  claim 20 , wherein at least one exit is graphically represented. 
   
   
       25 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 24 , wherein the graphic representation of an exit already passed is different from the graphic representation of an exit not yet passed. 
   
   
       26 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 24 , wherein only the exits not yet passed are graphically represented. 
   
   
       27 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 26 , wherein only the exits that can be reached at a speed less than their maximum exit speed are graphically represented. 
   
   
       28 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 24 , wherein the graphic representation of the exits that can be reached at a speed less than or equal to their maximum exit speed is different from the graphic representation of the exits that cannot be reached at a speed less than or equal to their maximum exit speed. 
   
   
       29 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 22 , wherein the moving graphic representations of the stopping distance or of the distance to reach the controlled speed of the aircraft do not jerk about. 
   
   
       30 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 24 , wherein the fixed graphic representations of the exits that can be reached or not at a speed less than or equal to their maximum exit speed do not blink. 
   
   
       31 . The system to assist in adjusting the braking intensity of an aircraft on a landing runway as claimed in  claim 24 , wherein the graphic representations of the exits are different in automatic braking mode and in manual braking mode.