How to calculate the furthest an animal could fly?

In my story several flying mythical creatures have been brought in a more realistic world. some creatures like Gargoyles can only fly for short distances while others like the heavenpiercer (a type of wyvern) which spends most of it's adult life high above the clouds. and i'm curious to know if there is an equation i could use to calculate the furthest one of these animals could fly by plugging in there length, wingspan, wingwidth, ect. or use to find the dimensions needed for a creature to fly a certain length?

• I doubt it's quite as simple as that. Take a European swift. Aerodynamic efficiency plays a big part, the apparent lack of need to land to sleep plays another part. 10 months on the wing is no mean feat for a bird about the size of a swallow (swallows are useless in comparison). Too many factors for a single simple equation. Feb 28, 2020 at 2:09
• the furthest an animal could fly? as far as it is fed.
– L.Dutch
Feb 28, 2020 at 2:10
• Simple; just use the average flight speed and the maximum time the bird is able to fly without needing to stop and there you get it. :grin: Feb 28, 2020 at 5:04
• Even actual existing animals don't have easy equations to calculate this. Just make it up. It'll seem more BS if you claim to have some kind of math behind it. Feb 28, 2020 at 5:15
• There clearly isn't an equation for this... why do you want it? I bet somebody could come up with a good enough equation for, like, a roleplaying game (although it will probably have some fudge factors). Feb 28, 2020 at 7:15

You can't. Flight endurance depends on not just the animal, but also the environment and circumstances. Even if you had an equation for the animal, real-world performance would still depend on environment and circumstances.

But, you can look at different bird morphologies to get a sense of what makes some birds fliers and other birds flitters.

The Albatross is famously adapted to long-duration flight, and can essentially stay in the air indefinitely. Pretty much the only thing they need to come back to land for is mating and hatching chicks.

https://www.smithsonianmag.com/science-nature/the-amazing-albatrosses-162515529/

Meanwhile, the turkey vulture is a scavenger. Because they never know when and where their next meal will be, they're capable of eating so much that they cannot fly. (Many other birds are also capable of eating so much that it affects their flying ability.)

https://www.yellowstonewildlifesanctuary.org/turkey-vulture

Other birds use wind patterns and columns of hot air called thermals to fly for long periods without flapping and expending almost no energy.

https://web.stanford.edu/group/stanfordbirds/text/essays/Soaring.html

There is no standard formula, but the basic principle is that birds have a certain store of energy, and exertion drains that store. At the same time, metabolic activity can replenish that energy even while it is being drained. If they use too much then they are exhausted and they have to stop until they have rested.

You can fly longer if you are more efficient (use less energy to fly, such as in the Soaring link above), or if you improve your ability to generate energy by increasing heartrate and lung capacity.

You can see this in people too. Any healthy and fit person can go out and run a few miles. An overweight person has to stop sooner and walk because they need more energy to run, and after a while they can run a little more. Marathon runners and ultramarathonners have trained to the point where they have boosted their energy-generation ability so they essentially run indefinitely.

For one more morphology, falcons are not particularly high-endurance birds, but they are very fast. The peregrine falcon can reach speeds over 200 miles per hour (320 km/h).

https://en.wikipedia.org/wiki/Peregrine_falcon#Feeding

• Though the falcon's speed is arguably not flying, but diving. Feb 28, 2020 at 7:20
• -1 for not elaborating on the ability to carry coconuts in flight coconuts, but +2 for the extensive, in-depth answer. Feb 28, 2020 at 11:18
• @Renan They could grip it by the husk Feb 28, 2020 at 14:12
• The albatross might not be landing on land, but it is landing on the sea at regular intervals to catch prey. If it doesn't, it will starve to death! :-) Feb 28, 2020 at 16:06