A question about giant pterosaurs taking off.

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I was watching a video about something (I forget what) and it mentioned that the common idea of these animals jumping off cliffs to get airborne is wrong and it's now known that these animals took off from level ground by jumping to get airborne and timing their first flap to gain lift at roughly the top of their take-off jump. I hadn't thought about flying animals taking off, so I watched some slo-mo footage of some modern birds taking off and that's how they do it.

But giant pterosaurs had a wingspan of over 10 metres. That makes me wonder how they got enough clearance for that first flap. Surely they couldn't jump 5 metres high. They weighed ~200Kg! Would a partial flap be enough to gain a little more height?

For the purposes of this question, assume that the pterosaur is not on a treadmill :)
 
Man of Honour
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I'd make a huge assumption they were a bit like swans in this respect and had the same kind of issues with flight.
 
Soldato
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I would also factor in that they may have had better lift with the skin rather than feathers. Also, reptiles are able to make huge bursts in acceleration due to how their muscles work, I know dinosaurs were not strictly reptiles but they could have had a similar bio function that was enough to launch the thing off the ground.
 
Soldato
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I heard the same theory, they based in on watching vultures and the like as I recall. don't remember the specifics but i'd guess if they lifted their wings and flapped down hard, given the size of the wing and the lift it would generate they'd gain height fairly fast. also, being as a wing is flexible and not like an aircraft wing, i'd thing it contacting the ground wouldn't be an issue - in fact, maybe it you actually give a bit of a shove upwards?
 
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I was watching a video about something (I forget what) and it mentioned that the common idea of these animals jumping off cliffs to get airborne is wrong and it's now known that these animals took off from level ground by jumping to get airborne and timing their first flap to gain lift at roughly the top of their take-off jump. I hadn't thought about flying animals taking off, so I watched some slo-mo footage of some modern birds taking off and that's how they do it.

But giant pterosaurs had a wingspan of over 10 metres. That makes me wonder how they got enough clearance for that first flap. Surely they couldn't jump 5 metres high. They weighed ~200Kg! Would a partial flap be enough to gain a little more height?

For the purposes of this question, assume that the pterosaur is not on a treadmill :)

I won't bother to speculate on the technique used to get airborne, but out of interest did they say how we 'know' this now? Did they discover old video footage?!
 
Man of Honour
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I was watching a video about something (I forget what) and it mentioned that the common idea of these animals jumping off cliffs to get airborne is wrong and it's now known that these animals took off from level ground by jumping to get airborne and timing their first flap to gain lift at roughly the top of their take-off jump. I hadn't thought about flying animals taking off, so I watched some slo-mo footage of some modern birds taking off and that's how they do it.

But giant pterosaurs had a wingspan of over 10 metres. That makes me wonder how they got enough clearance for that first flap. Surely they couldn't jump 5 metres high. They weighed ~200Kg! Would a partial flap be enough to gain a little more height?

For the purposes of this question, assume that the pterosaur is not on a treadmill :)
Oxygen/Climate conditions were different then too, these creatures would have had immense strength and agility.
 
Soldato
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I'd guess if they ran forwards with wings spread, but flat to air resistance, then jump and angle wings to generate some lift, and get an explosive first downwards movement, even if not too great, they'd get lift.

Be interesting to see if they developed models to test it.
 
Soldato
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As you mention they have skin wings rather than feathered.
As this is the case you need to think of them more like bats. From this, you can deduce that giant pterosaurs would hang upside down and drop into a glide.

Failing that, treadmills.
 
Associate
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200kg weight may be an overestimation. Higher oxygen did allow for higher metabolism, but skin is worse for wings than feathers, weighs too much for area.
Cliff edge start was probably the main way to take off.
For flat ground I saw a video modeling their take off.
Pterosaurs had access to quadripedal movement, using "knuckles" on wing limbs to push off the ground. Rear legs are weak and tiny, can't get any speed just out of those.
Strategy was broadly similar to swans, except on ground rather than in water. To pick up enough horisontal speed to get sufficient lift once it spreads wings basically inches from ground, utilize wing-in-ground effect, then slowly pick up altitude
 
Soldato
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That's cool, I do agree that cliff assist was probably their best bet (plenty of birds still do that, even though they can take off without), but getting into the air from the ground is probably an essential survival skill anyway. Even if you were huge.
 
Soldato
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I'd never considered how a Swan takes flight before reading this thread. Now I've just watched half a dozen videos of them taking off and it's hilarious at full speed.

No wonder they stay in the water!
 
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