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New aircraft rises 'like a balloon'

bbc.com

11–20 of 75 posts

Re: New aircraft rises 'like a balloon'

#11
post #5

With the soaring price of helium, I wonder what it costs to fill up that gas bag and how quickly it leaks out. And at what point filling it up costs more than the "almost expendable" aircraft. In the novel/film Contact the character S.R. Hadden lives in an airliner that rarely lands. With a larger Phoenix that lifestyle could become available to somewhat less wealthy billionaires. Maybe it could eventually become an…

There are no really great lifting gases. Steam is ok but must be kept hot. H2 is dangerously explosive. Vacuum is the best (a so-called "null ship") but no known material can maintain the hull pressure under vacuum.

Excuse the silly question if it is one, but would one option be not a full vacuum but only marginally lower density of air inside the balloon, supplemented by solar-powered propellers? Could there be a material strong enough to handle a minimal density difference to provide enough lift for it to work?

Re: New aircraft rises 'like a balloon'

#12
post #5

With the soaring price of helium, I wonder what it costs to fill up that gas bag and how quickly it leaks out. And at what point filling it up costs more than the "almost expendable" aircraft. In the novel/film Contact the character S.R. Hadden lives in an airliner that rarely lands. With a larger Phoenix that lifestyle could become available to somewhat less wealthy billionaires. Maybe it could eventually become an…

> Maybe it could eventually become an atmospheric variation of seasteading.

It's like a miniature version of the Venus cloud city idea, but here on Earth.

Re: New aircraft rises 'like a balloon'

#13
University of the Highlands and Islands is considered a bit of a second rate institution in Scotland.

A nice bit of publicity for them none the less.

Hopefully they can develop this more and more. Scotland needs a boost to Aerospace after we got another Space port last year

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

Re: New aircraft rises 'like a balloon'

#14

Earlier quoted context omitted.

There are no really great lifting gases. Steam is ok but must be kept hot. H2 is dangerously explosive. Vacuum is the best (a so-called "null ship") but no known material can maintain the hull pressure under vacuum.

Excuse the silly question if it is one, but would one option be not a full vacuum but only marginally lower density of air inside the balloon, supplemented by solar-powered propellers? Could there be a material strong enough to handle a minimal density difference to provide enough lift for it to work?

No not even diamond is strong enough to allow generating a useful amount of lift that way.

Re: New aircraft rises 'like a balloon'

#15

University of the Highlands and Islands is considered a bit of a second rate institution in Scotland. A nice bit of publicity for them none the less. Hopefully they can develop this more and more. Scotland needs a boost to Aerospace after we got another Space port last year https://en.wikipedia.org/wiki/Sutherland_spaceport

[deleted]

Re: New aircraft rises 'like a balloon'

#16

Earlier quoted context omitted.

There are no really great lifting gases. Steam is ok but must be kept hot. H2 is dangerously explosive. Vacuum is the best (a so-called "null ship") but no known material can maintain the hull pressure under vacuum.

Excuse the silly question if it is one, but would one option be not a full vacuum but only marginally lower density of air inside the balloon, supplemented by solar-powered propellers? Could there be a material strong enough to handle a minimal density difference to provide enough lift for it to work?

To add to your Idea, could a "null ship" be carried to a greater height and then where the air is thinner have it's gas removed to take everything a little higher?

Like rocket stages but for airships.

Re: New aircraft rises 'like a balloon'

#17
Most of the mentioned use cases involve high altitudes. Higher altitudes = higher winds. The air is smooth up there but it does move. For instance, the upper level winds above my head right now are pushing 130knots. This thing will have to do more than glide gently up and down if it wants to maintain station at 10km+, airliner altitude.

Re: New aircraft rises 'like a balloon'

#18

Most of the mentioned use cases involve high altitudes. Higher altitudes = higher winds. The air is smooth up there but it does move. For instance, the upper level winds above my head right now are pushing 130knots. This thing will have to do more than glide gently up and down if it wants to maintain station at 10km+, airliner altitude.

I was wondering about this too. Then again, I don't know the air density difference. 130 knots at half the density (not that I know if half density is a feasible figure) would impart something like half the force, I imagine. Then again, lower density affects the ability of craft that use density for lift to operate.

Re: New aircraft rises 'like a balloon'

#19
post #5

With the soaring price of helium, I wonder what it costs to fill up that gas bag and how quickly it leaks out. And at what point filling it up costs more than the "almost expendable" aircraft. In the novel/film Contact the character S.R. Hadden lives in an airliner that rarely lands. With a larger Phoenix that lifestyle could become available to somewhat less wealthy billionaires. Maybe it could eventually become an…

I believe Hadden lives on a space station in both movie and book.

Re: New aircraft rises 'like a balloon'

#20

Earlier quoted context omitted.

There are no really great lifting gases. Steam is ok but must be kept hot. H2 is dangerously explosive. Vacuum is the best (a so-called "null ship") but no known material can maintain the hull pressure under vacuum.

Excuse the silly question if it is one, but would one option be not a full vacuum but only marginally lower density of air inside the balloon, supplemented by solar-powered propellers? Could there be a material strong enough to handle a minimal density difference to provide enough lift for it to work?

Yeah I had this idea also, steam vapor at 1/8 atm might be easier than a full vacuum. Havent done the math, though.
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