# US 5,353,022 A · Airplane takeoff and landing performance monitoring system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,353,022 A - Document ID: US5353022A - Status: Granted - Kind: A - Application number: 08/045,337 - Filed: 1993-04-06 - Granted: 1994-10-04 - Earliest claimed: 1987-08-06 - Assignees: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration - Inventors: David B. Middleton; Raghavachari Srivatsan; Lee H. Person, Jr. - Web page: https://patentgrep.com/patent/US5353022A ## CPC - G05D 1/0083: {to help an aircraft pilot in the rolling phase} - G08G 5/21: located onboard the aircraft - G08G 5/52: for take-off - G08G 5/54: for approach or landing - G08G 5/55: for a single aircraft - G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES - G08G: TRAFFIC CONTROL SYSTEMS (guiding railway traffic, ensuring the safety of railway traffic B61L; arrangement of road signs or traffic signals E01F9/00; radar or analogous systems, sonar systems, lidar systems specially adapted for traffic control G01S13/91, G01S15/88, G01S17/88; {radar or analogous systems, sonar systems, lidar systems specially adapted for anti-collision purposes G01S13/93, G01S15/93, G01S17/93}) ## 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 (VR) 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 ### Claim 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 will 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 will 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; means for continuously displaying a fixed indicator indicative of a recommended engine operating condition on said display means; means for continuously displaying a movable indicator indicative of actual engine operating status in a spatial manner on said display means relative to the displayed fixed indicator; and means for altering the appearance of the movable indicator indicative of actual engine operating status in response to a difference between the actual engine operating status and a computed engine operating exceeding a predetermined tolerance level. ### Claim 2 (depends on 1) The monitoring system according to claim 1, further comprising 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 of the airplane and a predicted acceleration of the airplane. ### Claim 3 (depends on 2) The monitoring system according to claim 2, 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. ### Claim 4 (depends on 2) The monitoring system according to claim 2, 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. ### Claim 5 (depends on 2) The monitoring system according to claim 2, further comprising means for displaying a go symbol when the airplane acceleration error falls within the specified tolerance band and inadequate runway remains for the airplane to stop in a determined safe manner. ### Claim 6 (depends on 1) The monitoring system according to claim 1, wherein the means for continuously displaying a movable indicator indicative of actual engine operating status displays a first movable indicator on the right side of the runway indicative of the actual operating status of a right engine of the airplane and a second movable indicator on the left side of the runway indicative of the actual operating status of a left engine of the airplane. ### Claim 7 (depends on 1) 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 required for the airplane to reach the rotation speed at a nominal thrust. ### Claim 8 (depends on 2) The monitoring system according to claim 2, 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 required for the airplane to reach the rotation speed at a nominal thrust. ### Claim 9 (depends on 1) The monitoring system according to claim 1, wherein the size of movable indicator indicative of the actual engine operating status corresponds to the actual engine operating status. ### Claim 10 (depends on 2) The monitoring system according to claim 2, further comprising means for displaying an error symbol when a difference between the measured acceleration of the airplane and the predicted acceleration exceeds a minimum determined acceleration error, wherein the length of the error symbol corresponds to a current difference between the measured acceleration and the predicted acceleration. ### Claim 11 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 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 where the rotation speed of the airplane shall 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; continuously displaying a fixed indicator indicative of a predicted engine operating condition on said display means; continuously displaying a movable indicator indicative of actual engine operating status in a spatial manner on said display means relative to the displayed fixed indicator; and altering the appearance of the movable indicator indicative of actual engine operating status in response to a difference between the actual engine operating status and a computed engine operating status exceeding a predetermined tolerance level. ### Claim 12 (depends on 11) The monitoring method according to claim 11, further comprising 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 a predicted acceleration of the airplane. ### Claim 13 (depends on 12) The monitoring method according to claim 12, further comprising displaying a symbol on the displayed runway indicative of where the airplane can be stopped when the abort symbol is displayed. ### Claim 14 (depends on 12) The monitoring method according to claim 12, 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. ### Claim 15 (depends on 12) The monitoring method according to claim 12, further comprising displaying a go symbol when the airplane acceleration error falls within the specified tolerance band and inadequate runway remains for the airplane to stop in a determined safe manner. ### Claim 16 (depends on 11) The monitoring method according to claim 11, wherein the step of continuously displaying a movable indicator indicative of actual engine operating status comprises displaying a first movable indicator on the right side of the runway indicative of the actual operating status of a right engine of the airplane and displaying a second movable indicator on the left side of the runway indicative of the actual operating status of a left engine of the airplane. ### Claim 17 (depends on 11) The monitoring method according to claim 11, further comprising displaying a symbol on the displayed runway indicative of a position of the ground roll limit distance, wherein the ground roll limit distance is defined as the distance required for the airplane to reach the rotation speed at a nominal thrust. ### Claim 18 (depends on 12) The monitoring method according to claim 12, 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 required for the airplane to reach the rotation speed at a nominal thrust. ### Claim 19 (depends on 13) The monitoring method according to claim 13, wherein the length of movable indicator indicative of the actual engine operating status corresponds to the actual engine operating status. ### Claim 20 (depends on 12) The monitoring method according to claim 12, further comprising displaying an error symbol when a difference between the measured acceleration and the predicted acceleration of the airplane exceeds a minimum determined acceleration error, wherein the size of the error symbol corresponds to the current difference between the measured acceleration and the predicted acceleration. ### Claim 21 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 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; 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; and means for displaying an error symbol when a difference between the measured acceleration of the airplane and the predicted acceleration exceeds a minimum determined acceleration error, wherein the length of the error symbol corresponds to a current difference between the measured acceleration and the predicted acceleration. ### Claim 22 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; 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; and 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 required for the airplane to reach the rotation speed at a nominal thrust.