as the title, my question is how big a pelican like creature with its pouch mouth need to be in order to carry grown up human and still fly.

since as far as i know hollow bone is to fragile for human to ride big flying creature on their back, and i want to know the possibility by carrying them using pelican type of mouth, beside i am not good with math and only know stone age physic at best.

if its not clear, i dont mean the pelican eat them or swallow them, but just carry them inside the pouch as a flying transportation, and i do at least think a way to make sure they dont accidentally get swallowed by using cormorant fishing method by tying their neck to make sure they dont swallow thing as big as human size while maybe i can incorporate it into a leash too to control the flying.

  • the world is pretty much like earth

  • its fine if the answer end up says its impossible in reality, but at least provide the math or physic of it to show of how absurd it will be.

  • feel free to include or suggest alternative way if my method is impossible, (still related to the mouth) like for example carrying them like stork carrying baby either using cloth or basket like in this image.


enter image description here

and feel free to edit my grammar and the tag to the appropriate one, (though i appreciate it if this is not removed when you edit it, give other a chance to know that they are welcome to fix or edit this, because sometimes the edit is not perfect or still has some flaw)

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    $\begingroup$ It couldn't fly, it would be too big. I would suggest a note to accept that fact as the rest of it can be calculated. $\endgroup$
    – Separatrix
    Mar 27, 2020 at 8:58
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    $\begingroup$ Some of their favourite snacks weigh up to 3.5kg, let’s say they can comfortably fly with half that in their mouths... average human weight is apparently 62kg (sounds a bit light to me). It’s a gonna be a big bird. $\endgroup$ Mar 27, 2020 at 10:39
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    $\begingroup$ It's not hard to calculate the wing area * flap rate required to lift a given mass. It's much harder to claim any organic animal can support wings that size before bones and ligaments shatter. $\endgroup$ Mar 27, 2020 at 15:56
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    $\begingroup$ From a technical standpoint, there's nothing saying that organic animals can't eventually evolve to have jet turbines and aircraft grade aluminum skin. $\endgroup$
    – John O
    Mar 27, 2020 at 18:13
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    $\begingroup$ There's another problem beyond the bird not being able to fly (without super-powered muscles &c), which is weight and balance. There are fairly strict limits to where the center of gravity of a winged object can be in order to maintain stable flight. It can be a real problem in light airplanes (and sometimes even larger commercial ones), where having heavy objects too far forward or rearward can cause a crash. $\endgroup$
    – jamesqf
    Mar 27, 2020 at 18:16

1 Answer 1


The largest extinct flying birds include:

Agentavis magnificens:

The heaviest bird ever capable of flight was Argentavis magnificens, the largest member of the now extinct family Teratornithidae, found in Miocene-aged fossil beds of Argentina, with a wingspan up to 5–6 m (16–20 ft), a length of up to 1.26 m (4.1 ft), a height on the ground of up to 1.5–2 m (4.9–6.6 ft) and a body weight of at least 71 kg (157 lb).3

Harpagornis moorei:

Rivaling Argentavis in wingspan if not in bulk and mass, another contender for the largest known flying bird ever is Harpagornis moorei, which had a wingspan of up to 7.3 m (24 ft).7


Pelagornis sandersi:

The new species, Pelagornis sandersi, had an estimated wingspan of 20 to 24 feet (6.1 to 7.3 meters) when its feathers are included. This is up to more than twice as big as that of the royal albatross, the largest living flying bird, which has a wingspan of about 11.4 feet (3.5 meters).

To find out how P. sandersi could take off and stay aloft despite its giant size, Ksepka fed data about the bird's mass, wingspan and wing shape into a computer program designed to predict flight performance. The researchers estimated the bird weighed from 48.2 to 88.4 lbs. (21.9 to 40.1 kilograms).


The largest flying reptiles were even larger, real "terror dactyls".

I found a list of 18 species of flying reptiles with estimated wingspans greater than 5 meters or 16 feet. 11 of those species had estimated wingspans of 6 meters (20 feet) or wider, and 5 of them had estimated wingspans of 9.1 meters (30 feet) or wider.

The estimated wingspans of extinct birds include estimates of the length of their feathers at the wingtips, while the estimates for flying reptiles go to the tips of their wing bones.

https://en.wikipedia.org/wiki/Pterosaur_size#Pterosaurs_with_largest_wingspan 4

Some species of pterosaurs grew to very large sizes and this has implications for their capacity for flight. Many pterosaurs were small but the largest had wingspans which exceeded 9 m (30 ft). The largest of these are estimated to have weighed 250 kilograms (550 lb). For comparison, the wandering albatross has the largest wingspan of living birds at up to 3.5 m (11 ft) but usually weighs less than 12 kilograms (26 lb). This indicates that the largest pterosaurs may have had higher wing loadings than modern birds (depending on wing profile) and this has implications for the manner in which pterosaur flight might differ from that of modern birds.

Factors such as the warmer climate of the Mesozoic or higher levels of atmospheric oxygen have been proposed but it is now generally agreed that even the largest pterosaurs could have flown in today's skies.[17] Partly, this is due to the presence of air sacs in their wing membranes,[18] and that pterosaurs launched into flight using their front limbs in a quadrupedal stance similar to that of modern bats, a method faster and less energy taxing that the bipedal launching of modern birds.19

https://en.wikipedia.org/wiki/Pterosaur_size#Speculation_about_pterosaur_size_and_flight 6

The heaviest flying creature ever might possibly have been Quetzalcoatlus northropi:

Weight estimates for giant azhdarchids are extremely problematic because no existing species share a similar size or body plan, and in consequence, published results vary widely.5 Generalized weight, based on some studies that have historically found extremely low weight estimates for Quetzalcoatlus, was as low as 70 kg (150 lb) for a 10 m (32 ft 10 in) individual. A majority of estimates published since the 2000s have been substantially higher, around 200–250 kg (440–550 lb).5


At the present time, Asia is the continent with the lightest average adult human weight, at 57.7 kilograms (127.2 pounds), and North America is the continent with the heaviest average adult human wight, at 80.7 kilograms (177.9 pounds).


Thus the largest known flying creatures on Earth weighed a few times as much as an average adult human. Would that make humans weight a small enough fraction for them to be able to take off carrying the extra weight? What is the greatest fraction of its own weight that any bird has ever carried?

Would any flying creature have a long and wide enough lower jaw for an adult human to fit through the jaw and go into any pouch the flying creature might have had? Would such a pouch be strong enough to hold the weight of an adult human, or would the human tear through the pouch and plummet to their death?

Would the neck bones and muscles of the flying creature be strong enough to carry their head with the addition of the weight of an adult human?

If your setting is another planet, you might want to make it a planet with lower gravity and a denser atmosphere.

As a general rule, the higher the gravity of the planet the denser the atmosphere will be, but there are exceptions due to planetary conditions. For example, Titan has much lower gravity than Earth but a somewhat denser atmosphere, and Venus has slightly less gravity than Earth and many times as dense an atmosphere.

In a fantasy story, the giant flying creatures might be tamed by giants who train them for various tasks. At fairs the giants might offer rides on their giant flying creatures, or in their pouches, to dwarfs or halfings.

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    $\begingroup$ There's something wrong with your links... $\endgroup$
    – Matthew
    Mar 27, 2020 at 18:38
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    $\begingroup$ @Matthew The links all seem to work now, even though their numbers are still inconsistent. $\endgroup$ Mar 28, 2020 at 17:38

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