US 12,227,286 B2
Method of and transonically operating aircraft having devices for suppressing aeroelastic instabilities
Kai Backhaus, Wolfenbüttel (DE); Jürgen Arnold, Diemarden (DE); Holger Hennings, Rosdorf (DE); and Lorenz Tichy, Göttingen (DE)
Assigned to Deutsches Zentrum für Luft—und Raumfahrt e.V., Bonn (DE)
Filed by Deutsches Zentrum für Luft—und Raumfahrt e.V., Bonn (DE)
Filed on May 12, 2022, as Appl. No. 17/742,926.
Application 17/742,926 is a continuation of application No. PCT/EP2020/081465, filed on Nov. 9, 2020.
Claims priority of application No. 10 2019 130 596.9 (DE), filed on Nov. 13, 2019.
Prior Publication US 2022/0324553 A1, Oct. 13, 2022
Int. Cl. B64C 21/02 (2006.01); B64C 21/00 (2023.01); B64C 23/04 (2006.01)
CPC B64C 21/02 (2013.01) [B64C 21/00 (2013.01); B64C 23/04 (2013.01); B64C 2230/00 (2013.01)] 24 Claims
OG exemplary drawing
 
1. A method of suppressing aeroelastic instabilities on a transonically operating aircraft comprising a pair of wing halves that are configured so that a transonic flow forms spatially limited supersonic flow regions that each, in a main flow direction of the flow, end in a compression shock, the method comprising,
providing devices for suppressing aeroelastic instabilities on the transonically operating aircraft, wherein the devices for suppressing aeroelastic instabilities are configured for, in at least one supersonic flow region at at least one of the two wing halves, thickening-up a boundary layer of the flow temporarily when approaching a flight envelope of the aircraft with increasing flight Mach number of the aircraft,
wherein the devices for suppressing aeroelastic instabilities are configured to thicken up the boundary layer of the flow to such an extent that the compression shock at the end of the respective supersonic flow region at the present flight Mach number of the aircraft induces a separation of the boundary layer of the flow from the wing half, and wherein:
the transonically operating aircraft has an aircraft model specific Maximum normal Operating Mach number MMO between 0.7 and 1.0; and
the devices for suppressing aeroelastic instabilities comprise at least one of:
air exit points distributed in wingspan direction which are connected to activatable air supply channels, wherein the air supply channels are connected to motor driven or aerodynamically operative pressurized air sources; or
elements at the wing halves which can be activated into an aerodynamically effective position for thickening up the respective boundary layer, wherein the elements comprise activatable spoilers by which each respective wing half may be temporarily provided with a step extending crosswise with respect to the main flow direction and stepping back along the main flow direction.