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In this world, jetpacks among the "pack" part, also have wings, where the thrusters are suited, so you don't have to buy fireproof pants.

These wings are retractable when not in use, but aside from that, they aren't moving too much during flight (if they do, that's for direction changing).

  • The jetpacks were designed for use in Earthlike atmospheres.
  • Energy and fuel problems are not a concern (the "pack" part can turn the air into fuel)
  • The jetpacks are used both by military and civilians.

human using a jetpack
The Jetpack. Wingspan is 2,8 m

a bird's wing
A bird's wing

Would avian style wings with movable bone and muscle-like structures and artificial feathers, give any advantage to the jet pack?
Or would they be just for aesthetics?
Or would they be a hindrance?

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    $\begingroup$ You should wait at least 24 hours before accepting an answer to give other users a chance to look at your question and discuss the existing answer. It's your choice when to accept an answer, but you might get more unexpected answers by waiting a bit. As of writing this your question was asked one hour ago and has 29 views, which means that only a very small percentage of the people using WB.SE looked at your question. $\endgroup$ – Sec SE - clear Monica's name May 27 '17 at 21:02
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    $\begingroup$ @Secespitus He knows this. He's done the same things on many questions before; he's also high enough rep to know that by default by now even if we didn't point it out. $\endgroup$ – Aify May 27 '17 at 22:22
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    $\begingroup$ @Aify He's just been out of the latest suspension and his question ban, so I wanted to give him the chance to let the broader community have a view at his "first" question. I know very well how he acted in the past. $\endgroup$ – Sec SE - clear Monica's name May 27 '17 at 22:26
  • $\begingroup$ «turn air into fuel» the oxygen is considered the oxidizer not the fuel, and every airplane and automobile out there is air breathing. So this is not noteworthy in this context, and I think you misunderstand the fuel budget. $\endgroup$ – JDługosz May 28 '17 at 4:11
  • $\begingroup$ Please consider that in our world (let's assume there was a market for jet packs), if we had two designs, one was as you described a creepy birdwing and the other one was nice, the birdwing would only sell to a very small demographic and those people actually already buy wings and don't need jet packs attached to them. Also they don't wear it in public that often. While technically (if you can turn air into fuel, who cares anymore ...) your idea is possible, it is just horrible design $\endgroup$ – Raditz_35 May 28 '17 at 5:17
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Yes, they would be very advantageous for flight.

I presuppose that you allow not a 1:1 slavish rebuild of an avian wing, but a foldable wing with complicated (but now robust enough) inner workings changing the structure of the wing and overtaking the parts of flaps and slats.

Such wings can indeed perform maneuvers which are hard or even impossible for fixed wings. For example, if you land with a fixed wing you need to reduce speed, but you also still need lift, so with a fixed wing you need to increase the angle of attack if you do not want to fall out of the sky. A flexible wing in contrast can bend itself to slow you down quickly and give you the ability to a graceful pinpoint landing (Ever see a big bird landing?).

It also enables you to optimize drag conditions for different flight routines. And last but not least it allows enormous maneuverability by folding wings partly in flight.

All those conditions comes with a price: The mechanical complexity is enormous, so the wing must be really a very fine piece of work. But if it really works, it would rock.

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  • $\begingroup$ Nanotech is a handwave in my story and A.Is don't do it for the cash, that's one problem eliminated, 10/10, would Vote Up again. $\endgroup$ – Mephistopheles May 27 '17 at 20:53
  • $\begingroup$ Uh sorry, the accepting thing will be re-applied if 24 hours pass without... $\endgroup$ – Mephistopheles May 27 '17 at 21:15
  • $\begingroup$ What makes you so sure that those wings go together with the kind of thrust and speed a jet pack might create? I'm not an engineer, just curious $\endgroup$ – Raditz_35 May 28 '17 at 5:29
  • $\begingroup$ A jet pack must have per definitionem a better thrust to weight (including person) ratio than 1. It also needs something that allows to throttle the thrust continously otherwise you cannot land. You always need to stay upright without wings, because it is the only stable position which also limits the horizontal speed. Fixed wings are a vast improvement because you can now fly in lying position, gather speed and spare fuel , range and speed increase drastically (You can also see the difference between people free falling and using a wingsuit!). Adjustable wings are the next natural step. $\endgroup$ – Thorsten S. May 28 '17 at 9:50
  • $\begingroup$ This by the way demonstrates maneuverability beyond fixed wings. $\endgroup$ – Thorsten S. May 28 '17 at 9:58
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Incidentally, human birdwings are a reality, though the design is rather limited when compared to a bird's abilities to fold them, twist, turn, and dive.

Assuming the wearer has full control over the skeletal structure of each wing independently, the wing is significantly more manoeuvrable. It would allow the wearer to push and pull air in most any direction, similar to how flippers and webbed hands give humans added mobility in water.

However you'll need to consider the control systems, it's probably not trivial to give the user full control over each wing independently, although the basics for powered flight shouldn't be too difficult. In the video linked above, there is a separate blog post about the power mechanism he used.

If you're interested to go more deeply, there is a good structural analysis of bird wing design here, and feather arrangement.

The tradeoff will be directional velocity. Jetpacks have the clear advantage there. As far as I understand, winged creatures cannot exceed terminal velocity in a dive.

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  • $\begingroup$ The birdwings would still have the thrusters. $\endgroup$ – Mephistopheles May 28 '17 at 7:41
  • $\begingroup$ Winged creatures cannot exceed terminal velocity in a dive. Uh, yes? Unpowered creatures can only drop so fast as when their wing efficiency is 0. If something is powered, the speed limit is given when the thrust is equalled by air resistance. As wings have lift and cause therefore induced drag, winged designs are slower downwards than unwinged designs, but they are by no means limited by terminal velocity. $\endgroup$ – Thorsten S. May 28 '17 at 10:08

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