Airplane takeoff and landing performance monitoring system

• US 5,499,025 A
• Filed: 07/21/1994
• Issued: 03/12/1996
• Est. Priority Date: 08/06/1987
• Status: Expired due to Fees

• Current Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Original Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Inventors: Srivatsan, Raghavachari, Middleton, David B., Person, Lee H. Jr.
• Primary Examiner(s): Swarthout, Brent
• Application Number:
  US08/281,799
• Time in Patent Office: 600 Days
• Field of Search: 340/959, 73/178 T, 364/427, 364/428
• US Class Current: 340/959
• CPC Class Codes: G05D 1/0083 to help an aircraft pilot in the rolling phase
• CPC Class Codes: G08G 5/0021 located in the aircraft
• CPC Class Codes: G08G 5/0065 for taking-off
• CPC Class Codes: G08G 5/025 Navigation or guidance aids radar or analogous systems specially adapted for landing purposes G01S13/913

Abstract

The invention is a real-time takeoff and landing performance monitoring system for an aircraft which provides a pilot with graphic and metric information to assist in decisions related to achieving rotation speed (V_R) within the safe zone of a runway, or stopping the aircraft on the runway after landing or take-off abort. The system processes information in two segments: a pretakeoff segment and a real-time segment. One-time inputs of ambient conditions and airplane configuration information are used in the pretakeoff segment to generate scheduled performance data. The real-time segment uses the scheduled performance data, runway length data and transducer measured parameters to monitor the performance of the airplane throughout the takeoff roll. Airplane acceleration and engine-performance anomalies are detected and annunciated. A novel and important feature of this segment is that it updates the estimated runway rolling friction coefficient. Airplane performance predictions also reflect changes in head wind occurring as the takeoff roll progresses. The system provides a head-down display and a head-up display. The head-up display is projected onto a partially reflective transparent surface through which the pilot views the runway. By comparing the present performance of the airplane with a continually predicted nominal performance based upon given conditions, performance deficiencies are detected by the system and conveyed to pilot in form of both elemental information and integrated information.

Claims

1. In an airplane takeoff and landing performance monitoring system with a display means for graphically and continuously depicting the position of an airplane on a runway, the improvement comprising:

means for generating a value indicative of a rotation speed of the airplane necessary to achieve take-off;

means for continuously displaying both a stationary symbol indicative of an initial prediction of a position where the rotation speed should occur and a movable symbol indicative of a current prediction of a position where the airplane should reach the rotation speed on the runway wherein the movable symbol is superimposed on the stationary symbol when there is no difference between the initially predicted position of the airplane and currently predicted position of where the airplane should reach the rotation speed and wherein the movable symbol is spatially distanced from the stationary symbol along the runway when there is a difference between the initially predicted position and the currently predicted position; and

means for displaying an abort symbol when an acceleration error of the airplane exceeds a specified tolerance band, wherein the acceleration error is defined by a difference in a measured acceleration and an initially predicted acceleration of the airplane.

2. The monitoring system according to claim 1, further comprising means for displaying a symbol on the displayed runway indicative of where the airplane can be stopped when the abort symbol is displayed.

3. The monitoring system according to claim 1, further comprising means for displaying a go symbol when the acceleration error is within the specified tolerance band and the current speed of the airplane exceeds a predetermined decision speed.

4. The monitoring system according to claim 1, further comprising means for displaying a go symbol when the airplane acceleration error falls within the specified tolerance band but inadequate runway remains for the airplane to stop in a determined safe manner.

5. The monitoring system according to claim 1, further comprising means for displaying a symbol on the displayed runway indicative of a position of a ground roll limit distance, wherein the ground roll limit distance is defined as the distance from the point where the takeoff roll begins to the last point on the runway at which the airplane upon achieving rotation speed, can, with one engine inoperative and using scheduled throttle settings, clear a predetermined height at the departure of the runway.

6. A method of monitoring an airplane takeoff and landing performance including graphically and continuously depicting the position of an airplane on a displayed runway, the improvement comprising:

generating a value indicative of a rotation speed necessary to achieve takeoff;

continuously displaying a stationary symbol on the runway indicative of an initial prediction of a position where the rotation speed of the airplane necessary to achieve take-off should occur;

continuously displaying a movable symbol on the runway indicative of a current prediction of a position where the rotation speed should occur, wherein the movable symbol is superimposed on the stationary symbol when there is no difference between the initially predicted position where the rotation speed of the airplane should occur and currently predicted position of where the rotation speed of the airplane should occur, wherein the movable symbol is spatially distanced from the stationary symbol along the runway when there is a difference between the initially predicted position and the currently predicted position; and

displaying an abort symbol when an acceleration error of the airplane exceeds a specified tolerance band, wherein the acceleration error is defined by a difference in a measured acceleration of the airplane and to initially predict acceleration of the airplane.

7. The monitoring method according to claim 6, further comprising displaying a symbol on the displayed runway indicative of where the airplane can be stopped when the abort symbol is displayed.

8. The monitoring method according to claim 6, further comprising displaying a go symbol when the acceleration error is within the specified tolerance band and the current speed of the airplane exceeds a predetermined decision speed.

9. The monitoring method according to claim 6, further comprising displaying a go symbol when the airplane acceleration error falls within the specified tolerance band but inadequate runway remains for the airplane to stop in a determined safe manner.

10. The monitoring method according to claim 6, further comprising displaying a symbol on the displayed runway indicative of the position of a ground roll limit distance, wherein the ground roll limit distance is defined as the distance from the point where the takeoff roll begins to the last point on the runway at which the airplane upon achieving rotation speed, can, with one engine inoperative and using scheduled throttle settings, clear a predetermined height at the departure of the runway.