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(Related to Human Dragonfly wings)

Context

The mutant thread is back. For more context, see my previous questions.

One of my character is a "subtle" mutant (no outward sign) that has an affinity for biotechnology. Being able to interact and direct evolution of simple organisms, he chose to fight crime by designing a series of gadgets using biological mechanisms that can be found in nature, and mostly in insects.

One of those gadgets has to make him able to fly.

Question

(The thread mentioned above asks for a biological solution. I'm asking for a reasonable biotechnological solution)

Assuming access to sufficient energy, I looked into the advantages two pairs of light and flexible flapping wings would offer over a single pair. So far, I listed a few:

  1. Two sets of wings allow for better air control and maneuverability, faster acceleration and stationary flight. Some sources (coming up) I read mention also that the two-pairs option is more energy-efficient by about 20% for stationary flight (second pair helps in reducing energy waste).
  2. A dragonfly wing is comparatively thinner and weighs less than a bird wing (relatively to their respective sizes). I suppose this means flapping an insect-like wing requires comparatively less energy than flapping a bird-like wing. Having two sets would mean you can also share the required surface for lift-off between the two sets.
  3. Mechanically, it would probably be easier to emulate the movement of a insect wing, with no joints, than the movement of a bird's wings (that need joints and motors built-in to the wing). Following that, you could probably fold your insect wings with more ease than mechanical bird like wings.

The user of this "flying-backpack" using two pairs of wings:

  1. Use them outdoor, not indoors, in an urban environment. So they can be quite large, but the smaller the better.
  2. Won't haul cargo. So you "just" need the lift-off for 90~95kg of human and gear.
  3. Has access to a high-power, short duration source of energy, so he will probably use the wings for a few short trips (hundreds of meters) per day during short periods of time. (I don't know if the duration impact the answer - could be relevant to the stress put on the wings)

Is such device plausible (specifically, can it generate enough lift to actually fly, or does it need to be paired with some sort of jetpack)?
Answers who can provide maths relative to lift and precise the required wing surface/span/relevant parameter as well as any supplementary thrust that you would need are appreciated.

The other thread mentions the flapping speed of dragonflies. I suppose this is important when calculating the lift, so that and every other relevant parameter is up to the answerer to answer why or why not it would be feasible.

Edit 1: On the technology you can use, the character is about "enhanced biologic stuff". Example, enhanced arachnid silk for bulletproof vest. You can assume whatever the wings are made of are scaled-up, enhanced versions of their biological counterparts (in the way you need it - more resistant, more flexible, better heat dispersion, etc). Sadly, no force-field.

Edit 2: The question was a bit blurry, so I cleared it out to focus on: Is it plausible? I want to know if I can use such a device in my story without making it out of handwaivium.
As pointed by Lucas A, some other insect wing disposition might be better suited so feel free to post an answer for insect-like wing flying kit with a different wing patterns, as long as it is insectoid and you can provide a reason why it would be better suited. Edit 3: Excerpt from comments:

Exactly, power source is the handwaved part. Count about 80kg of pilot, 10 kg of gear and "battery" max and the remaining being the wings (the last 15 kg are negociable, I'm not fixed on the character being exactly 80kg )


In "folded" position, the wings need to be as unencombering as possible. So having them in the body axis, along the back would be preferable. So let's go for about 50cm (shoulder width) by 1m or so (back length + a bit is okay)

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  • $\begingroup$ What level of technology can we throw at the problem? Forcefields would resolve some of the mass related issues on the wing speed. $\endgroup$ – Separatrix Feb 13 at 14:01
  • $\begingroup$ The character is more about "enhanced biologic stuff". Exemple, enhanced arachnid silk for bulletproof vest. You can assume whatever the wings are made of are scaled-up, enhanced version of their biological counterparts (If that was your problem). Sadly, no force-field. $\endgroup$ – Nyakouai Feb 13 at 14:03
  • $\begingroup$ The SE Q&A model is one-specific-question/one-best-answer. I count three questions. Further, the help center states that questions of the form "your answer is provided along with the question, and you expect more answers" are unacceptable. This question is currently too broad, having too many questions, and downvotable for not conforming to help center question expectations. Please remember that SE is not a discussion forum. I will retract my VTC and DV if the Q is satisfactorily improved. $\endgroup$ – JBH Feb 13 at 19:45
  • $\begingroup$ True, the question is ill phrased. I'll try to correct that as soon as possible $\endgroup$ – Nyakouai Feb 13 at 21:09
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    $\begingroup$ Could the people downvoting please comment so I know what is the problem with this question? $\endgroup$ – Nyakouai Feb 17 at 1:13
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I believe it's plenty plausible, yes. (Assuming a handwavium power source)

The main problem of "personal flight" systems has always been the power source. Combustion (jet packs) require heavy fuel that is expended relatively quickly. The weight of battery packs is generally too large, compared to their power output, to make them viable. External sources, like solar, are not efficient enough. Nuclear is too dangerous for "personal" use. Etc. The handwavium energy source bypasses all of those complications.

The next problem would be structural integrity. Applicable animal based (especially insect) structural materials, other than maybe bone or leather (which are decidedly NOT insectoid material), don't really have stress tests done on them at these scales, so accurate strength information is all but impossible to find (I wasn't able to find any that is relevant to the sizes dealt with in this question, but maybe they exist somewhere). However, having said that, I suspect that Chitin (and other components of arthropod cuticle), the main component of insect wings and exoskeletons (as well as the exoskeletons of coconut crabs and lobsters), can be scaled up sufficiently for human use, while still remaining both strong enough and light enough for flight, given an appropriate power source. If we can grow a human ear on the back of a mouse, or grow spider silk in goat's milk, it should be no great (relative) challenge to grow some Chitin in the shape of a giant dragonfly wing.

The final issue is keeping it small, fitting in to about backpack size. Depending on the desired appearance, and level of mobility needed while folded, the options on this one can vary quite a bit. While Dragonflies, specifically, don't actually fold their actual wings, they just lay them across their back, some insect wings can fold quite compactly. An in-between option would be ladybird beetles (ladybugs) that fold their wings on 2 main seams, making 3 main sections. Personally, I'd go with 2 panels/sections on each of the 4 wings, 8 total "panels". Each panel being roughly 40-50 cm by 70-80 cm. (which also ends up being the total area of the 'backpack' when completely folded and stored. But that's just my preference

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You're going to need some handwavium, but two issues stand out to me:

  1. "Following that, you could probably fold your insect wings with more ease than mechanical bird like wings."

Insect wings don't fold the way you seem to be thinking of, as if they could fit into a backpack. The wings would be a fixed size and shape, and your character would have to be very aware of them to refrain from sitting on them, knocking them into things, closing doors on them, etc.

For reference, Meganeuropsis was the largest dragonfly ever, and only had a wingspan of 28 inches (71 cm) and a body length of 17 inches (43 cm). Your wings will have to be much larger in order to provide lift for a character that's taller than a foot and a half.

  1. Whether or not these extremely can provide the necessary lift is dependent on how you're supplying power to them, as well as how large and what shape they are.

Meganeuropsis lived when oxygen levels were much, much higher than they are today, and that made supplying flight muscles with oxygen proportionally easier.


https://en.wikipedia.org/wiki/Meganeuropsis

I answered a similar question that involved dragonfly wing anatomy awhile ago. I just checked that the links are still good. You can find it here:

Creating a Scientifically Semi-Valid Pseudo-Arthropod Primate Part 1: Pseudo-Dragonfly Wing Rib Muscles

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    $\begingroup$ While folding the wings wasn't my main concern, the link provided incidentally led me to a string of other questions that have been incredibly valuable. Still doesn't solve my problem for wing span, though, but I can approximate some things with the info of the other question. So +1 $\endgroup$ – Nyakouai Feb 18 at 10:03
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This may seem slightly irrelevant, but have you thought of having a compact design, and a broader-wing design?

Your broad design could be based off of your dragonfly design, it would be useful in large open areas where its manoeuvrability and speed could shine.

For a compact design it could be based off of a Bee, their secrets of flight (Previously aeronautical engineers had "proven" that bee's could not fly) have only been discovered recently. Their wings sweep back in a 90' arc, then flips over as it returns. Additional vortices are produced by the rotation of the wing, and as the wing flaps in its own wake it is more efficient than flapping in still air. Secrets of bee flight.

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    $\begingroup$ Two nitpicks. a) nobody "proved" the bee couldn't fly, people did prove that we were unable to model the mechanism by which it did (so we developed new models that could), and b) bee-style flight only works on small scales. On larger scales, the square-cube law comes into effect, and this style of flight no longer works. $\endgroup$ – Gryphon Feb 15 at 2:14

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