# US 2010/0168937 A1 · Method for Flight Control of a Plurality of Aircraft Flying in Formation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2010/0168937 A1 - Document ID: US20100168937A1 - Status: Published application - Kind: A1 - Application number: 12/063,186 - Filed: 2006-08-03 - Published: 2010-07-01 - Earliest claimed: 2005-08-09 - Assignees: EADS Deutschland GmbH - Inventors: Marco Willem Soijer; Manfred Zoberbier; Roland Goerke - Web page: https://patentgrep.com/patent/US20100168937A1 ## CPC - G08G 5/53: for cruising - G05D 1/104: {involving a plurality of aircrafts, e.g. formation flying (traffic control systems for aircraft G08G5/00)} - G08G 5/55: for a single aircraft - 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}) - G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES ## Abstract In a method for the flight control of a plurality of aircraft flying in formation with respect to one another, correction signals are generated for an autopilot system or a command display in order to allow one or more following aircraft within the formation to follow a lead aircraft in the formation in a predeterminable relative position. A nominal trajectory of the following aircraft, parallel to the trajectory (1) of the lead aircraft, is calculated at each instantaneous position P′act of the following aircraft, which trajectory runs through the instantaneous actual position P′act and a reference point P′RP. (The reference point P′RP is the projection of a point PRP, which is separated by the longitudinal nominal distance xnom between the lead aircraft and the following aircraft, on the trajectory of the lead aircraft, taking into account the lateral and vertical actual distances yact and zact between the trajectory of the lead aircraft and that of the following aircraft. The trajectory of the following aircraft is calculated taking into account the lateral actual distance yact from the trajectory of the lead aircraft by determining support points P′ on the trajectory of the following aircraft which have the same time coordinates as the corresponding support points on the trajectory of the lead aircraft. The correction signals are determined by i) measuring the longitudinal, lateral and vertical actual distances xact, vact and zact between the trajectory of the lead aircraft and that of the following aircraft at the instantaneous position P′act of the following aircraft, ii) calculating the longitudinal deviation Δx, the vertical deviation Δz and the lateral deviation Δy of the instantaneous actual position P′act and of the nominal position P′nom of the following aircraft from the respective nominal values xnom, znom, ynom and the measured actual values xact, zact, yact, iii) calculating the nominal speed and the nominal acceleration of the following aircraft at the point P′RP, and iv) calculating the nominal curvature, the nominal climbing rate and the nominal curvature angle Ψ of the trajectory of the following aircraft at the instantaneous position P′act of the following aircraft. ## Claims ### Claim 1 A method of flight control for a plurality of aircraft flying in formation with respect to one another, with correction signals being generated for an autopilot system or a command display in order to allow one or more following aircraft within the formation to follow a lead aircraft in a predeterminable relative position, said method comprising: at each instantaneous position P′act of the following aircraft, calculating a trajectory of the following aircraft, which is parallel to the trajectory of the lead aircraft, with the calculated trajectory of the following aircraft running through an instantaneous actual position P′act and a reference point P′RP, that is the projection of a point PRP which is separated by the longitudinal nominal distance xnom between the lead aircraft and the following aircraft, on the trajectory of the lead aircraft, taking into account the lateral and vertical actual distances yact and zact between the trajectory of the lead aircraft and that of the following aircraft; calculating the trajectory of the following aircraft taking into account the lateral actual distance yact from the trajectory of the lead aircraft by the determination of support points P′ on the trajectory of the following aircraft which have the same time coordinates as the corresponding support points on the trajectory of the lead aircraft; and determining correction signals by the steps of measuring longitudinal actual distance xact, lateral actual distance yact and vertical actual distance zact between the trajectory of the lead aircraft and that of the following aircraft at the instantaneous position P′act of the following aircraft; calculating a longitudinal deviation Δx, a vertical deviation Δz and a lateral deviation Δy of the instantaneous actual position P′act and of the nominal position P′nom of the following aircraft from the respective nominal values xnom, znom, ynom and the measured actual values xact, zact, yact; calculating nominal speed and nominal acceleration of the following aircraft at the point P′RP; calculating a nominal curvature, a nominal climbing rate and a nominal curvature angle Ψ of the trajectory of the following aircraft at the instantaneous position P′act of the following aircraft. ### Claim 2 (depends on 1) The method according to claim 1, wherein: a plurality of support points P are determined on the trajectory of the lead aircraft; and for the support points P, the space coordinates are known and a time coordinate is known with respect to a time basis which is uniform for the formation. ### Claim 3 (depends on 1) The method according to claim 1, wherein a ground course angle Ψ of the following aircraft is determined as the angle between a direction of the trajectory (2) of the following aircraft and its instantaneous position P′act and the true north. ### Claim 4 (depends on 1) The method according to claim 1, wherein the reference point PRP and the reference point P′RP have the same time coordinate. ### Claim 5 (depends on 2) The method according to claim 2, wherein time-tagged support points P on the trajectory of the lead aircraft are equidistant to one another. ### Claim 6 (depends on 1) The method according to claim 1, wherein the longitudinal deviation Δx in a length indication is determined as the sum of individual length segments adjacent support points between the support point of reference point P′RP and the actual position P′act of the following aircraft. ### Claim 7 (depends on 1) The method according to claim 1, wherein the longitudinal deviation Δx in a time indication is determined as the difference between the time coordinate of the support point of the reference point P′RP and the actual position P′act of the following aircraft. ### Claim 8 (depends on 1) The method according to claim 1, wherein the trajectory of the lead aircraft is calculated as the trajectory of a following aircraft relative to a lead aircraft of a higher-ranking formation. ### Claim 9 (depends on 1) The method according to claim 1, wherein the lead aircraft transmits an actual spatial position and an actual time coordinate to at least one following aircraft, by radio.