Dragon flight muscles

Question

So, Mark Witton had a lengthy article on why paleontologists think the Quetzalcoatlus northropi could fly.

One interesting thing about it is that Witton and Habib think the Quetzalcoatlus had a 90-second window of anaerobic wing flapping to gain altitude, then transitioned to soaring, with glide ratios similar to storks.

Now dragons could do something like this, for everything else there's magic. However, they have to carry an extra pair of legs and a tail, and most likely a larger torso (though you can have most of it filled with air).

I don't have any concrete numbers, so we'll go for the maximum:

• The muscle fibers need the highest power output, with the least mass, i.e: a high specific strength
• How much of this muscle fiber can be packed into the dragon, assume similar flight mechanics (muscle and tendon placement, etc) to birds
• Tendons have the same tensile strength as spider silk, approx 1.3 GPa, bones are reinforced with goethite fibers, I tried to find a compressive strength, but with no results
• The flight muscles will only be used for 90 seconds

So, yeah, I basically ask if it's possible to create muscle tissue through biological processes (and a quite long time span) that can fulfill these criteria.

Answer 1

this is not just a problem of strength of the muscles than a problem with how big the wings are compared to the animal. There is a feedback loop inherent in flight, larger animals require proportionally larger wings thanks to the square cube law. if you make the wings bigger or heavier to move more air they that also adds weight, and you reach a point where the weight you add is more than the weight to can shift. If you make an animal much larger than a Quetzalcoatlus the wings end up being too large to be structurally sound, the bones and tendons can't withstand the forces needed to shift enough air to counter the animals mass. worse this also shifts more of the animals mass into the wings, so eventually the wings weigh more than the rest of the animal. There is also the issue that larger wings must beat slower, meaning there is a scale of diminishing returns for making the wings bigger.

source 1

source 2

As for making stronger muscles, there is no scientific way to make stronger muscles, evolution has had abundant drives to make stronger muscles and has not found a way. Muscles are already extremely effice power to weight wise. Comparable to electric motors. You need something like a rocket or jet engine to exceed it. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC123619/

Answer 2

Airplanes could fly. What airplanes do is to have tremendous power pushing them forwards, then because their wings are shaped so that the wind has to go faster on top of the wings than lower, creating lower air pressure above the airplane, so it goes upwards. You could do that with the wings, and the dragon could "paddle" through the air extremely fast so that it would go upwards, which would work.

Another method would be the dragon being lighter than air, so that it would actually float in the air like a helium balloon, or a submarine, where it could control it's float or sink. This would be possible if the dragon had something like a muscular helium injector to this large bubble inside of it.

But what you are asking is for it to be like a bird, to use it's downwards force extending it's wings, and gets it up making the wings smaller, so it gets more strength flapping downwards than upwards. This would be easy to do if it had this tendon on it's wing tip which it could control in flight. It also has to have muscles in it's connection between it's wings and it's body, strong enough to flap like that for 90 seconds.

I suggest you use all three, the first on it's body, and the others on the body and wings, the dragon could then be large enough to pose a threat while still being able to float. It also provides vulnerabilities at the tendon and the bubble, and because the bubble needs to refill it makes sense then that the dragon cannot fly immediately when being opposed to in it's lair.