Can you fly a plane on a gas giant?

[RCgothic]

It's not possible to fly on a gas giant for very long. It takes roughly 3x the power to maintain level flight. There's no way to turn bouyancy to your advantage without enormous heating power expenditure. There's no way to refuel. It takes way too much DV to escape to even a low orbit. When out of fuel the vessel will sink and be crushed. At any level that flight is possible gravity will be uncomfortable to intolerable to crew. 

Only nuclear powered craft would have any endurance in a gas giant's atmosphere and even they would eventually succumb.

[4D4850]

Gas giants and ice giants (a term that is or was used for Uranus and Neptune), at least in the Solar System, don't have oxygen, so a traditional airbreathing engine wouldn't be possible. In addition, it was mentioned previously how density is so low in the atmospheres of the giants that flight would be difficult. This means that (if I'm correct) pressure would be significantly higher where an Earth rocketplane could fly, which would be bad for those materials. However, if you made a submarine with wings, or something like it (a pressure-resistant rocket plane), it would, in theory, be possible to fly. Just my 2 cents, though, and I might be completely wrong.

[RCgothic]

XKCD WhatIf also covers gas-giant submarines: https://what-if.xkcd.com/138/

Although it doesn't specifically combine the two, I'm not sure what adding a submarine hull gets you. The craft can stand a higher density/pressure so needs less wing, but it's much heavier, so it needs much more wing, and it's flying at a much hotter level, which requires exotic cooling, which requires more wing and more power. My gut feel is that this isn't a net gain.

Do not exceed depth for a modern submarine (~300m >30bar) isn't even 200km below the 1bar level (at 71.5k km radius).

I'm not sure a submarine hull changes the basic conclusions.

[Davi SDF]

Perhaps if you had a nuclear reactor powered aircraft, and even then it would definetly be hard since a Gas Giant's atmosphere is very low density.

But with big enough wings, powerfull enough nuclear reactors and some damn good avionics, I would say definetly yes!

Edited March 14, 2022 by Davi SDF