Every pilot admires the way birds fly (most birds, anyway). But researchers at the University of Central Florida (UCF) Department of Mechanical and Aerospace Engineering have launched a study on how birds execute their best “perching” maneuver—landing on tree branches, wires or other tight spots.
The group found that some birds pitch their wings upward to a high angle of attack just before touchdown, while others fold their wings, instead, in a sweeping motion that helps them decelerate with great precision. Doctoral aerospace engineering candidate Dibya Raj Adhikari observed that the sweeping motion enables enhanced control of aerodynamic forces by changing the shape of the bird’s wings, just as extending flaps and slats do on an airplane, but with much more minute adjustments.
“A complete understanding of this perching maneuver,” Adhikari said, “would help to quantify the performance of the natural flyers and aid in the design of safer aircraft.” “This perching maneuver also allows the birds to land smoothly within a short distance,” he added, suggesting that somehow mimicking the swept-wing characteristics of these birds could enable shorter landings for aircraft.
The university’s research has found that the swept-wing motion stabilized the leading-edge vortex, one of the main aerodynamic elements that enhance lift. “This stabilization ultimately leads to a better landing in birds—and potentially in aircraft,” according to UCF. You can read the group’s findings here in the engineering online outlet Physical Review Fluids.
Sitting on the deck watching the smallest of birds making near suicidal feints and attacks on the big Red Tail hawk who is trying to penetrate the defensive screen to get at the chicks in the nests for a snack. The screams and squawks have to be heard as they make their runs and then break violently away to avoid getting eaten themselves.
Aerobatics with no grace, just violent G pulling snap rolls and spins.
Watching Cardinals fly across my yard at full speed and land in the small holes of my chain link fence is unbelievable. Their full body and wings tucked just fit inside the holes. I would love to see that in slo-mo.
LOL – I’ve seen birds do this too. Incredible!
Cooper’s Hawk’s are agile, they roll to large angle to go between trees and buildings.
In general, birds move wings and perhaps body quickly to finish the landing, balancing.
Or… pilots could learn best landing techniques and practice accordingly, enhancing safety in that manner rather than adding complexity to the hardware. Though I do agree, there is a lot to be learned from birds, such as how to stay up all afternoon making no more than one circle in each thermal, and how to get my engine to run on earthworms and seeds. JK (= disclaimer)
The owl has the largest wing per pound of any bird. Weight or size, speed and mission all come into play in the design of birds. Human designers tend to forget that birds were not made to carry tons of cargo, many passengers, fly at supersonic speeds, burn fuel at the rate of 1 gal per second or be used in warfare. When flying is simplified such as in sailplanes, hang gliders or motorgliders, bird design can be really useful. Just think of how many major problems could be solved if we all could own or have access to personal flight. Mans problems and anxieties of life have all been brought upon himself. In that arena, birds cannot help us!
Well, birds have to survive, many do not.
Mortality of Great Blue Herons is 50% in first year of life, foraging skills are a problem, hogging of food by adults as well. In contrast, crows keep their young with them through their first winter.
After hangaring my plane a few years ago, when looking up at the sky and observing an approaching thunderstorm close by, seeing an eagle soaring, thinking that it knew where to be and when not to be there, and that only birds know how to truly fly.
I have a bird feeder outside my dining room window, so I watch several varieties of birds every morning durning breakfast. Some of them are extremely talented, speeding in at breakneck speed and landing wherever they’ve chosen to land, absolutely perfectly. Some others speed in at breakneck speed, miss the perch, and go around for another stab at it. And unfortunately some fewer speed in at breakneck speed, miss the perch, hit the window, and break their necks.
The only real difference I’m seeing between the birds and sitting on the sidelines watching pilots land at OSH is that the birds all wait until the very last second to slow down. Of course, that’s true of some pilots, too, I guess. It’s all fascinating.
Interesting stuff, but I’m not sure how these studies will ever apply to fixed wing or GA aircraft. Honestly my only concern with the flight of birds is how well they (and me) react in cllose proximity in the same airspace. THEN I hope that birds are good at doing fancy manuvering!
Ahrg, Just had 2 close encounters with birds in the pattern this afternoon after writing the above.
I see an imperative for artificial intelligence as how these amazing landings of aircraft will become reality… I don’t see human sense/react/perform as capable in any scenario of achieving the reliable and save razor thin margins of a landing song bird or even an eagle.
Who would have imagined?
God’s flying machines are better than our own?
Low level high speed formation flying while avoiding obstacles. Just look to Mallards. I live on a pond and their twilight arrivals and departures are always amazing
As a South Florida native I’ve always enjoyed the outdoors including the diversity of bird species in our unique environment. Once I earned the ability to fly my focus changed and I started learning more details about the many cool birds in our skies. The latter is a more gratifying and educational experience. One of the coolest birds we enjoy part of the year is the Swallow-tailed Kite.
https://www.audubon.org/field-guide/bird/swallow-tailed-kite?site=fl§ion=search_results#
The way they employ the V-tail reminds me of an F-22
https://www.youtube.com/watch?v=jSWgXz994XE
BTW the Swallow-tailed Kites life cycle and migration patterns are unique and worth additional exploration.
The Kite is my favorite. They put us to shame without much effort!
‘Who would have imagined?
God’s flying machines are better than our own?’
Only in religion will one find competition in a spiritual creation.
‘the university’s research has found that the swept-wing motion stabilized the leading-edge vortex, one of the main aerodynamic elements that enhance lift’
Am I mistaken, but is this what vortex generators help accomplish on the wing leading-edge?
There are also studies about how a fly lands upside down on a ceiling, mind boggling. Although they have to get through a learning process too as this short video shows. https://www.youtube.com/watch?v=3pbXy9vyahQ&ab_channel=ScienceMagazine
THAT are some really “bounces” they make, and what would we call a missed approach for them, (DA) for Drop Around or so? 🙂
Landing gear that grabs, whoa!
This video is very enlightening about how flies maneuver as well. https://www.youtube.com/watch?v=jBPFCvEhv9Y
Great video! It’d be great to see what Bertorelli can do on this topic.
If my airplane could only flex its wings like a bird and dump all that lift, then I’d be able to land on a branch, too. Of course, my main wheels would also have to be equipped with talons to grab the branch. It might be a few years before they figure out how to do that.