Pegasi versus Pterosaurs · 8:49pm Oct 17th, 2016
In Top Bolt we get to see more pegasi showing off their amazingly awesome flying skills. Can we ever have too much of that? It really is quite impressive what they can do—from high-speed horizontal rolls to supersonic drives. But perhaps the most impressive physics-defying move is the way they can hover in mid-air with the daintiest little flaps of their wings, not creating the slightest breeze to inconvenience anypony else. All this, together with the walking-on-clouds thing, kind of suggests that pegasus flight has not so much to do with differential air pressure, but is instead sustained by some combination of magical high-octane flutterpony dust and a big shot of narrativium. Even if a gust of wind at a forty-five degree angle can propel you into a flipping loop.
In our more restricted world, where movement is harshly constrained by the laws of physics, could a winged pony ever get off the ground?
Last year, students from University of Leicester compiled a short project entitled The Wings Of Pegasus. Using a simple mathematical model of flight, they estimate that to stay airborne, a 600kg horse would need wings of area at least 15.8 square meters, or a wing span of over ten metres. Not the kind of friend you would want to have flying inside your house. Fortunately it would seem this factor is not so critical in Equestria.
Is such a creature actually possible? The next step in the calculation would be to determine how much energy it would need to fly, which might conclude that it necessitates a rather efficient metabolism, and an awful lot of oats. The largest flying creatures we can see today are birds like the albatross and Andean condor, which can have a wing spans of over three metres, yet weigh only about 11kg, thanks to light-weight hollow bones and other avian tricks.
If we take a historical perspective, our world can do much more awesome than that. Go back 65 million years, when dinosaurs walked the Earth, the skies above them were filled with pterosaurs, some of which grew to have a wingspans of over ten metres. It is believed they migrated enormous distances around the prehistorical world. Landing on the ground, they would have stood as tall as giraffes, and probably weighed in at over 200kg.
Quite how these giants managed to get into the air is a bit of a mystery, even allowing for the fact that the atmosphere was a bit thicker in those days. Once up there they would have glided and soared on thermal currents like large modern birds, but what about take-off? Some researchers have suggested they could only achieve this by jumping off cliffs, or even questioned whether they flew at all (although no one has proposed an alternative reason why they would evolve such big wings).
But pterosaurs did not fly like birds. This had their own tricks and probably moved more like bats. Mark Witton (University of Portsmouth) proposed a theory that instead of jumping into the air on their legs, they used their powerful wing muscles to propel themselves into the air in a kind of pole vaulter mechanism to achieve the necessary vertical acceleration.
This does lead to the question of whether pterosaurs ever existed in Equestria, before ponies, griffons and dragons took to the skies. And if so, what sort of tricks did they get up to at the Wondersaur Academy? Another research project for Petunia Paleo.
Insert seapony joke.
Shoutout to Horizon for his "Tear a dactyl" pun in Thou Goddess
Hmmm, interesting point. The only justification for the wing gust maneuver (possibly tying into the direct wing lifting) is that the wind is a by-product that exists because in the ponies minds (or by narrative imperative, if you prefer) it SHOULD exist. The actual magic, literally, is in a transfer of magic energy, channelled through the wings.
I would think some kind of flying saurian being existed in prehistoric Equestria. Dragons had to come from somewhere.
And we've actually seen proof that magic is necessary for pegasus flight. Tirek quite handily demonstrated that sucking them dry allows gravity and aerodynamics to team up and steal their proverbial lunch money.
4259793
My colt - sorry I cod not do better. Of horse I can always fish out some more mare-ine puns. They might well sound a little pony. Let me mullet over.
4259808
We do all have so much fun finding the most pterrible dinosaur puns in the thesaurus.
4259871
Maybe the wings are just for oramentation and it's all just a trick to boost confidence?
4259935
Ah yes - presumably the pegasaurus.
4259964 No, I think the wings do serve a purpose. Consider Scootaloo and Bulk Biceps. They have tiny wings and can barely fly. I would venture to guess that instead of moving air, the wings move magic, so to speak. This would still require a minimum wingspan (or wing flap rate in Bulk Biceps' case) to achieve sufficient lift, but it wouldn't follow quite the same rules of aerodynamics. Hmmm... suppose magic acted as a semi-permeable fluid in the sense that that only interacts with other magic things. This would also explain why a distributed magic field can allow a unicorn to hover, but why the non-magical animals of Equestria still seem to obey Earth rules.
...The question is if the properties that requires fit with other uses of magic. That would take a little more time to work out than I care to spend on it, though.
4259964
At this point I think your audience is getting salty. I think you need some fresh water puns.
4259808
not even sorry
4260001 I've always seen it as moving the magic in the air.
4260001
Fortunately, you can do it by proxy, since I've previously spent time on that exact subject myself (you're welcome!). Short version: yes, though the details of how they end up compatible vary depending other choices the author makes regarding magic in the setting. As a bonus, it also provides a potential Watsonian rationale for why pegasi might "gallop" while flying, as shows up a couple of times: the "fluid magic" may well be sufficiently push-off-able to let their legs generate lesser but still significant effects, letting them boost performance at (presumably) the cost of disproportionately increased energy consumption.
Also, don't forget to account for the other knock-on implications of that explanation! Aether currents in addition to normal wind and water ones, analogous "solid magic" that's impermeable to magical beings and items but which nonmagical ones pass through just fine, magical geography/oceanography/etc that make magical effects vary from place to place like "mundane" environments influence more familiar physical effects... there's a lot of fun stuff to be extrapolated from the premise.
4260355 That's more or less the same thing.
4260396 Link? I was referring mostly to in the show... head canon overlays complicate matters further. There need not be 'solid' magic, actually. Hydrogen, for instance, has no solid phase, and the Lumineferous Aether theory (which plays into my model of the Equestrian solar system) required a viscous fluid that had no (known) solid phase. I would say that clouds that Pegasi build on would qualify... but it's been established that an additional spell is needed for unicorns and earth ponies to walk on them, indicating it's not purely magically solid on its own, but only by interaction with a specific magic frequency. Kind of like the reverse of how antennae pick up specific frequencies.
I saw a paper (Pineta linked to it somewhere) where someone spent over 200 pages deriving an 8-dimensional relativistic quantum field to describe magic. Didn't get through the whole thing. Frankly, I've got other things to do... including but not limited to real world physics. Also writing and video games.
4259964
So if you had the ponysaurus and the pegasaurus, would there also be a uniceratops?
Magical dinosaurs sound kinda amazing, actually.
4259964 I may have very slightly laughed a bit way too hard at 'thesaurus'.
4260396
Ooh, that makes me want to dream up some cool stuff so much! Not that I actually write any of it, but oh it gives so many ideas...
Yikes, sorry about the ridiculously super-late response. After my first comment I ended up way too busy to reply for like a week (as they say, free-time flees when you're having "fun"), and I, uh, kind of forgot about it by the time I could actually do so. Thanks to 4304826 for the reminder!
4260455
As far as I'm aware, there's not really any significant canon info on how magic actually works in the show, so every interpretation is pretty much entirely headcanon. To use the obvious example, the semi-permeable fluid magic idea under discussion is hardly the only explanation for pegasus flight that's consistent with what's been shown so far.
You're thinking of helium, which has no solid phase at standard pressure but can solidify under more intense compression. So far as I know, all chemical substances end up in solid form under at least some conditions. Though of course, that doesn't mandate that magic need follow suit unless it's also chemical in nature (an idea which I've yet to see attempted; if anyone does write a story trying to make that work, I'd definitely be interested in giving it a read).
It wasn't stated in my original comment, but I hadn't actually been thinking of cloudwalking as an example of the solid magic idea, though it would be compatible with it in a fashion analogous to the one you describe (at least, assuming I'm interpreting what you said there correctly...).
Anyway, note that the ideas in the second paragraph were meant more as examples of possible ways one could extend the concept, not things that specifically must result from it. The main point was that while the details will vary depending on the choices the author makes, there will always be broader implications as a result, and it's important to think them through, both to shore up the story and because a lot of the time the extended effects are very interesting themselves. I just jotted down a few possibilities off the top of my head that seemed like they'd best capture the imagination - and judging by 4304826's response, that part appears to have worked!
4305284 ...Now it's been too long and I'm not sure where I was going with some of what I said. XP I'll give it a shot, though.
Fair enough, but I don't thiiiink that's what I meant (again, been awhile). I think I was trying to ask whether the semi-permeable magic fluid model has implications that are contradictory to the effects of magic seen in the show (at least without introducing additional complicating factors: Occam's Razor applies in that case).
This one I do know what I was thinking. I did mean hydrogen, but I was confused. I knew that at VERY high T-P, Hydrogen is a liquid (called liquid metallic hydrogen): https://en.wikipedia.org/wiki/Metallic_hydrogen What I did not know is that there is an intermediate point at which it is solid. I was, in fact, confusing that point with Helium, which as you say requires low T (1-1.5 K!) and high P (in the MegaPascals apparently) to form a solid. It's 'solid' phase, though, is semi-fluid. https://en.wikipedia.org/wiki/Helium What I should have said is that there exist materials which have no solid phase under atmospheric pressure or lower, regardless of temperature. Actually I'm not sure what ones there are other than Helium... my thing is physics, not chemistry.
I was mostly ravelling a thread, so by the end I was saying that's it's not a 'proper' example. Reading it back, it was a bit confusing. Cloud walls, however, would probably qualify. Unless Pegasi building routinely get broken up by ponies like Rainbow Dash in seasons 1-4ish who aren't so good at the stopping part of flying... which would be good for silliness but less so for a serious story. XP
I'm pretty sure I was trying to say something like this and not communicating it well. :P
4305386
Ah, gotcha. I'm not aware of it having any implications that are inherently incompatible with the evidence as seen thus far.
4305284
This could be a lot of fun. I'm studying to get a Bachelor's in Animal Behavior right now and I already have an Associate's in Marine Science, so the oceanography stuff especially gave me some ideas. I love how the natural world works and is infinitely complex, and dreaming up a world with magic is just extra fun. 
Lol, glad I could help! I should jot down ideas I come up with based on some of the suggestions you made--which you're right, were just the thing to stimulate the imagination
4305526 Another good excuse for Sea Ponies. XP
4305535
Oh yeah, you better BELIEVE I like to daydream of seaponies xD
4307618 Feel like I gotta say it.
Shoo-be-do. Shoo-shoo be do!
4307650
I found this post linked from another in my globe feed, anyway…
The ponies of Equestria mostly seem to be closer to Falabella miniature horses and most would be around 100kg as most. Unfortunately, I couldn’t load the paper to see if I could run the calculations with a significantly smaller horse to calculate the necessary wingspan for a mini horse.