# What kind of g-forces do birds experience and how does it compare to humans? [closed]

So bit of an odd one, but I was just looking at a sea-gull flying and wondering what kind of G-forces it could see in day to day flight?

There are probably very fast birds of prey that when pulling out of dives must experience fairly high G Force, but can they (in general) handle more or less than a human flying an aircraft?

• Fun fact: The fastest bird in the world, the Peregrine falcon (240 mph in a dive) has pop-up vortex generator feathers delay flow separation during a dive! (But no winglets @Peter Kämpf) – TomMcW Jan 10 '17 at 14:24

Birds regularly experience up 10-14 G according to this website. After looking at how birds and insects fly, scientists came up with the conclusion as to how birds cope with this is because:

Animals will always have some advantages over machines, such as the ability to use their nervous systems to sense subtleties about the environment around them and alter their flight accordingly.

further up near the top, it mentions comparisons between birds and high performance military aircraft, such as this:

A Blackbird jet flying nearly 2,000 mph covers 32 of its own body lengths per second. But a common pigeon covers 75 of its body lengths a second. The roll rate of the aerobatic A-4 Skyhawk plane is about 720 degrees per second. The roll rate of a barn swallow is more than 5,000 degrees per second. Some military aircraft can withstand gravitational forces of 8-10 G (Earth's gravity is equal to 1 G). Many birds routinely experience G-forces greater than 10 G and up to 14 G.

According to another website the reason humans can't cope with high g's as well is because:

Every bit of our muscular-skeletal system is naturally crafted to deal with Earth’s gravity. Were you to travel to a planet that had a more significant gravity, a more massive planet with 5 G’s for example, you would either be unable to lift yourself off the ground, our the new weight-force would be so much that the air would be forced out of your lungs and your eyes would explode (something gruesome for sure).

• crazy stats about the pigeon covering it's own body twice as fast as an SR-71! and the 5000degs/sec roll rate. thanks for the informative answer! – andy-m Jan 10 '17 at 14:12
• How long does it take for a bird to pull out of a dive? The bird's body might change orientation in less than 0.1 seconds, but that doesn't imply that the first's downward momentum won't continue for some time after that. – supercat Jan 10 '17 at 16:33
• That claim about 5Gs causing human eyes to explode etc. sounds suspiciously like bunk. John Stapp is probably grimacing in his grave. – bright-star Jan 10 '17 at 18:49
• There is a type of pigeon called a Birmingham Roller that spins backwards at 10 or more revolutions per second (if they are good rollers). Very fast Rollers have been known to spin so fast that after they land there is occasionally blood in their eyes (broken capillaries). I think someone calculated that at 10 rps, they experienced 12-13 G's at the parts of their body at the outer edge of the spinning circle. The 10 rps is not a made up number - they have been filmed and the revolutions counted. – user19106 Jan 10 '17 at 22:57
• Fighter pilots routinely experience 5 Gs without any exploding of eyeballs. But they only experience it for relatively short periods of time. Living on a 5 G would is almost certainly possible, but it would present great physical challenges, at least for a while and possibly for life in some ways. One would eventually build up the muscles that would help deal with the increased gravity, and one would probably do little but sleep and eat and walk around briefly for the first several months at least. But I doubt it would be short-term fatal, although it might shorten lifespan. – Todd Wilcox Jan 11 '17 at 3:36