Inventors:
Kioumars Najmabadi - Clyde Hill WA, US
William F. Shivitz - Renton WA, US
Edward Ernest Coleman - Forest Park WA, US
John Koon-hung Ho - Shoreline WA, US
Richard D. Johnson - Edmonds WA, US
William F. Carver - Shoreline WA, US
David W. Grubb - Monroe WA, US
Robert James McIntosh - Bothell WA, US
Assignee:
The Boeing Company - Chicago IL
International Classification:
G01C 23/00, G06F 17/10, B64C 3/58
US Classification:
701 3, 701124, 244 49, 244213
Abstract:
A computer implemented method, apparatus, and computer usable program product for symmetric and anti-symmetric control of aircraft flight control surfaces to reduce wing-body loads. Commands are sent to symmetrically deploy outboard control surfaces to shift wing air-loads inboard based on airplane state and speed brake deployment. Surface rate retraction on a wing with peak loads is limited to reduce maximum loads due to wheel checkback accompanied by utilization of opposite wing control surfaces to retain roll characteristics. Airloads are shifted inboard on a swept wing to move the center of pressure forward, thereby reducing the tail load required to perform a positive gravity maneuver. In a negative gravity maneuver, speed brakes are retracted, thereby reducing the positive tail load and reducing the aft body design loads. High gain feedback commands are filtered from wing structural modes above one hertz by a set of linear and non-linear filters.