Most sensible air travelers dread turbulence. A little atmospheric hiccup can shake airplanes, rattle nerves and spill beverages. A Cornell-led collaboration has found that birds don't mind at all.
By combining wind speed data with the measured accelerations of a golden eagle outfitted with GPS tracking instruments, the researchers suggest that, rather than hindering flight, turbulence is a source of energy that birds may use to their advantage.
This counterintuitive discovery could revise what we know about avian flight, and help the aerospace industry develop faster, more efficient ways to fly in turbulent environments.
[...] While the flight of birds may appear easy and graceful to earthbound spectators, winged animals are actually navigating air flow that is structured, textured and constantly in flux, according to Gregory Bewley, assistant professor in the Sibley School of Mechanical and Aerospace Engineering, who led the team.
[...] In order to take his experiments out of the lab and into the sky, Bewley's team partnered with two groups -- Conservation Science Global and Cellular Tracking Technologies. Scientists from these companies captured a female golden eagle in Alabama, rigged it with a solar GPS telemetry unit with an accelerometer weighing less than 3 ounces, then released the bird.
[...] They found a "highly irregular, fluctuating pattern" in the eagle's accelerations, which resembles the typical trajectories of particles in turbulent airflows. At timescales ranging from 0.5 to 10 seconds -- which translates to approximately 1 to 25 wingbeats -- the eagle's accelerations and atmospheric turbulence were completely in synch.
[...] "If you could find a path in which every vortex is pushing you the right way, then obviously you get there a little faster with a little less energy," Bewley said. "We're still working hard to understand turbulence by itself. I think it's fascinating that there might be some practical empirical knowledge embodied in wildlife that we don't appreciate yet."
Journal Reference:
Kasey M. Laurent, Bob Fogg, Tobias Ginsburg, et al. Turbulence explains the accelerations of an eagle in natural flight [$], Proceedings of the National Academy of Sciences (DOI: 10.1073/pnas.2102588118)
(Score: 1, Insightful) by Anonymous Coward on Tuesday June 15 2021, @08:55AM (1 child)
When your wings are your fingers; you feel your way around the winds. I will bet (without googling it) that birds have more nerves in the wings more than about any part of the body. Except of course the ding-a-ling bell.
(Score: 0) by Anonymous Coward on Tuesday June 15 2021, @02:41PM
Modded insightful because you knew the ACs would add that final sentence if you didn't.
(Score: 0) by Anonymous Coward on Tuesday June 15 2021, @01:34PM (3 children)
turbulent flow and its cousin, chaos, don't actually look that erratic.
throwing the output of a calculation back into the original equation yields pattern that a normal person would not deem "random".
for " turbulent flow" ofc the main problem seems to be that there cannot be a one-to-one mapping of a single particles trajectory; math (and i am not good at it) has no way to map a curve or trajectory that loops back onto itself (in turbulent flow, a particle might move against the general flow, multiple times).
but the human mind does "see" patterns in turbulance and chaos and it looks like birds can predict and adapt to this turbulence.
i don't find the fact that birds "feel the way to fly" instead of "calculating" it, astonishing (but as mentioned, i am no math nerd). also you can ride a bike without knowing math.
(Score: 1) by js290 on Tuesday June 15 2021, @02:38PM
(Score: 0) by Anonymous Coward on Tuesday June 15 2021, @02:43PM
> math (and i am not good at it)
has no way to map a curve or trajectory that loops back onto itselfLet me stop you there so you don't embarrass yourself any further.
(Score: 2) by JoeMerchant on Tuesday June 15 2021, @06:59PM
>throwing the output of a calculation back into the original equation yields pattern that a normal person would not deem "random".
That depends entirely upon the equation... many will converge to a point, many more will explode to infinities, and among the oscillators there are strong periodic oscillations, quasi-periodic oscillators, and chaotic oscillations which tend toward the random - within some bounds.
I would imagine like Eskimos and all their words for snow, the birds have "many words" to describe turbulence and these would characterize the texture of it and the degree to which it can be exploited, possibly also the scale of the periodicity which may determine whether it gives more advantage to big birds or little birds.
Україна досі не є частиною Росії Слава Україні🌻 https://www.pravda.com.ua/eng/news/2023/06/24/7408365/
(Score: 2) by JoeMerchant on Tuesday June 15 2021, @06:55PM
If I were a bird, I'd be looking first for every free ride up that I could get - forward propulsion is nice too, but the real energy sink for birds (which fly in circles mostly when not migrating) is gaining altitude.
Україна досі не є частиною Росії Слава Україні🌻 https://www.pravda.com.ua/eng/news/2023/06/24/7408365/