A collaboration between University of Michigan aerospace engineers and University of British Columbia biologists has revealed that the key to agility in bird flight is quickly switching between stable and unstable gliding. It had long been assumed that bird flight was almost entirely unstable.
Traditional evolutionary theory concluded that birds were steadily evolving toward less stable flight, but this research has shown that bird flight involves decidedly stable phases. By studying physical bird wing physiology and developing computational software to simulate flight, researchers discovered that birds can manipulate the stability of their flight by changing their wing configuration.
This discovery is important to the design of aircraft, most specifically in the design of uncrewed aerial vehicles (UAVs) that may need to handle navigation in crowded urban areas and staying balanced in gusty winds.
The findings were published in the journal Nature on March 9, 2022 in a paper titled, "Birds can transition between stable and unstable states via wing morphing"
nature.com/articles/s41586-022-04477-8