For some things, sure. But, the issue is that the two gases that you might use are either flammable, or in absurdly short supply. (unless we crack the fusion problem soon)

TTFN (ta ta for now)
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Why don’t you knock it off with them negative waves?

another day in paradise, or is paradise one day closer ?

But, it's my PASSION, and I'm pretty good at it

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
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thx for the LPS ... it took time (a couple of minutes) to find the quote.

another day in paradise, or is paradise one day closer ?

An Oddball way of looking at things

"Know the rules well, so you can break them effectively."
-Dalai Lama XIV

Congratulations. You get a cookie.

Love that movie.

RB...

Considering new lightweight fabric materials for H2-gas impermeability and strength/stiffness/toughness... and navigation-autonomous-communication flight systems... and high efficiency light weight solar cells and batteries [including rapid plug-in recharging] and high efficiency electric-motor propulsion... and sensors that can be tuned for tramp H2 detection... and environmental threats and mitigation... [static/lightning, etc]... and visibility finishes and lighting for anti-collision... this is NOT at all a crazy idea, to me.

In fact... in locations/climates of stable fair weather [western US, deserts, etc] it seems outright feasible... and sorta fun challenge... to me.

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

If I take a regular latex rubber balloon and rub it on my head it will stick to the ceiling. I've done this and sometimes the balloon will remain in place for days.

Can the same principle be used to stick blimps in the sky so they don't need hydrogen or helium to stay up? Seems about as practical.

Until then I'm working on sail driven automobiles. The tough part is selling the DOT on zig-zag highways for when one needs to tack upwind.

Len
1) at altitude, there is usually clear skies, above the clouds.
2) I thought of the solar cells as a way to recharge the batteries, not necessarily to charge on the ground. If cloudy, then plug in to recharge.

another day in paradise, or is paradise one day closer ?

RB.. Yep... 'dust accumulation' is likely to be insignificant above the pollution/inversion layers... although 'forest/range-fire smoke' could be a problem.

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

I'm no proponent of blimps or electric propulsion... but, if you're going to do it, bring extra H2 onboard for

1. replenishing the gas bags
2. powering a fuel cell for the electricity

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

I used to work with someone who was a chief engineer for an Airship program. His comments on airships were they were a bit lost cause really. I recall him commenting that with Helium it was difficult to prevent leakage.
Hydrogen was explosive over such large mixture range(5% to 95% I think) that its a very hard risk to manage. An interesting couple of a sides, was that the mass for docking loads was 3 x the weight of the airship due to the airmass traveling with the ship & that they tend to bridge gusts, so the loads aren't as simple as aircraft.


You are stuck with a S/L lift capacity of ~ 1kg per Meter^3, so @35000 ft ~270 gm/m^3 & 132 gm/m^3 @ 50,000 ft. I think we need to move to a planet with a thicker atmosphere to see the rise of airships.

airships seem to come round every decade or so.

Their plus points are fairly specific uses and the down side many.

This lot are one of a few I think. https://www.hybridairvehicles.com/

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

I don't understand why a vacuum airship isn't given more thought with before mentioned new lightweight materials.
fire up a jet, suck the air out... let it float up. slowly let air back in, increase weight get the load on wings and fly fast. follow directions in reverse for landing. I mean even if you had it fractionally reduce wing load that would be neat.

A vacuum has only a slight advantage over H2 and HE in terms of buoyancy in air.
I guess the structure to support the vacuum might weigh quite a bit, fully erasing this advantage. Then there's the problem of maintaining the vacuum, i.e. counteracting leakage.

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

yes, the structure to support a vacuum would be ridiculously heavy

another day in paradise, or is paradise one day closer ?

Been awhile sine I've seen the Goodyear Blimp.

Perhaps the blimp idea on a 'UAV' scale has more merit?

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

Quote:

Perhaps the blimp idea on a 'UAV' scale has more merit?

Not in any military discussion, I don't think; blimps are large and slow, two things that military UAS' try to avoid being. To carry a Shadow UAV's payload would require a couple thousand cubic ft of He and present a target that's roughly 100 times bigger

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
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Ahhhh…

BUT with a small submarine 'shape' with all-moving tiny wings and stabilizers' [fore/aft?], radar transparent/absorptive body material, low IR/vis 'day/night' coatings, and radar hidden/absorptive components [surveillance, electronics, propulsion, etc]... and 'SATCOM' and guidance/nav antennas along the upper-back [pod-sheltered or pod-retracted-stored], etc... this 'slow mover' at moderately high altitude might be essentially invisible... it would have to be 'stumbled-over' to spot it.

I suggest using slow-turning/silenced pusher-counter-rotating all plastic variable pitch props for forwards/backwards movement... with the ability to pitch-yaw the props... for precision aiming/movement.

Hey, just dreaming the possibilities...

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

One possible use of blimps, or actually, super-pressure balloons https://en.wikipedia.org/wiki/Superpressure_balloo..., would be as radar pickets at the borders of a country to detect hypersonic glide vehicles. They would be flying around 30 km altitude, where the winds are close to zero, allowing them to potentially stay on station for months at a time.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
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"blades" ... sounds either (radar) noisy or "steam-punk" ?

I wonder if you could use the Dyson fan effect to generate thrust ? Maybe for the cruise engines that need only low power, and "proper" engines for "proper" control/thrust at lower altitudes ?

another day in paradise, or is paradise one day closer ?