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-   -   Airship Hulls (https://ecomodder.com/forum/showthread.php/airship-hulls-29121.html)

aerohead 05-31-2014 04:25 PM

Airship Hulls
 
Here are some airship hulls,with position of maximum cross-section aligned,and normalized to a constant cross-section with the lower table,noses aligned with the first.They're all streamline bodies of revolution.None of them 'cheat'.They maintain the classic streamline form.
http://i1271.photobucket.com/albums/...ntitled1-1.jpg
http://i1271.photobucket.com/albums/.../Untitled3.jpg
The bottom airship of the lower table would have the lowest drag of all the ships.It would not necessarily be the 'best',as it would be prone to giving the crew airsickness.Longer ships are preferred as a camera,electronics, or weapons platform.

bobdbilder 06-01-2014 09:38 AM

What do you think about this from Hybrid Air Vehicle UK. They brought back to UK a working unit that was supposed to see action in Afghanistan with the US military.

http://hybridairvehicles.com/images/range.jpg

user removed 06-01-2014 10:08 AM

I always like the idea of an inflatable pedal powered aircraft. Using a lighter than air gas, for inflation, would reduce the effective weight of the plane-pilot combo, but it would probably not be practical in any wind conditions.

regards
Mech

bobdbilder 06-01-2014 11:53 AM

I think there was an electronics packages such as EMP generators that never lived up to expectations. It has propulsion units sitting aft which means it sucks air right from the ...er...end.

Military Surveillance - Hybrid Air Vehicles Ltd

freebeard 06-01-2014 02:50 PM

An earlier tri-hull airship was the progenitor of the Aeron 26.

https://encrypted-tbn3.gstatic.com/i...e2kMUlJzJgppmr

It was destroyed in ground test when a crosswind sent it @ss over teakettle. Here's the Aeron itself, the 'Deltoid Pumpkinseed':

https://encrypted-tbn0.gstatic.com/i...nC_v4QEihJpRBa

Old Mechanic -- When the comedian Gallagher demoed a pedal power airship he did it inside a theatre (in 1985).
https://www.youtube.com/watch?v=3D63PK2IyJ4

Xist 06-01-2014 02:59 PM

Anyone ever hear of the Bussman Biplane?

freebeard 06-01-2014 03:11 PM

Google sez "Did you mean: Busemann Biplane ". A supersonic biplane?

Here's another indoor blimp, with rotors similar to the Aeromodeller2 in an airship hangar:
https://www.youtube.com/watch?v=-c9xUVjfcZM

Xist 06-01-2014 08:42 PM

Quote:

Originally Posted by freebeard (Post 427493)
Google sez "Did you mean: Busemann Biplane ". A supersonic biplane?

I stand corrected.

I was always intrigued by the amount of actual science that I learned from science fiction, although I was never quite certain of all of it, but that was from some novel that I read years ago.

The idea was that you could exceed the speed of sound without creating a sonic boom if you did not have wings and in order to fly, you needed a dirigible, so you basically had two circular airfoils inside of each other, filled with helium.

Sounds complicated! :D

freebeard 06-01-2014 11:01 PM

A supersonic zepplin? Sounds complicated.

I'd go will a tensegrity dome for the zepplin hull with pure steam as a lifting gas and a blimp bag inside filled wih hot hydrogen at a slight vacuum.

Xist 06-01-2014 11:30 PM

Quote:

Originally Posted by freebeard (Post 427558)
A supersonic zepplin? Sounds complicated.

I'd go will a tensegrity dome for the zepplin hull with pure steam as a lifting gas and a blimp bag inside filled wih hot hydrogen at a slight vacuum.

I read one novel where a guy floated using a sphere filled with vacuum. I am going to guess that it was powered by a tiny stable black hole.

elhigh 06-02-2014 09:58 AM

Quote:

Originally Posted by Xist (Post 427563)
I read one novel where a guy floated using a sphere filled with vacuum. I am going to guess that it was powered by a tiny stable black hole.

The tinier they are, the more unstable they become, until *poof* it vanishes in a blast of raw heat and x-rays and, oddly, radiated gravity.

Ironically if you feed them on a regular basis, that tends to cool them down and they stabilize and remain docile. Kind of like having an edgy Doberman.

Physics is weird.

doviatt 06-02-2014 10:55 AM

Quote:

Originally Posted by Xist (Post 427563)
I read one novel where a guy floated using a sphere filled with vacuum. I am going to guess that it was powered by a tiny stable black hole.

Quote:

Originally Posted by elhigh (Post 427595)
The tinier they are, the more unstable they become, until *poof* it vanishes in a blast of raw heat and x-rays and, oddly, radiated gravity.

Ironically if you feed them on a regular basis, that tends to cool them down and they stabilize and remain docile. Kind of like having an edgy Doberman.

Physics is weird.

But, if you tie one (black hole) to a stick and hang it off the front of your airship....now that, is fast!:)

freebeard 06-02-2014 12:09 PM

All this talk about black holes goes right over my head. Aren't black holes an hypothetical construct offered by astronomers who can't or won't accept the implications of plasma physics on a galactic scale?

Anyway, Magdeburg hemispheres - Wikipedia, the free encyclopedia. Vacuum bubbles don't scale.

OTOH pure steam has approx. the same lift as helium. The Flying Kettle Project - balloons and airships filled with steam!

EDIT: Here. This is an icosahedral cage around a tensile bag, stretched to a 3.2 fineness ratio.

http://ecomodder.com/forum/member-fr...2-10-11-32.png

A more developed design would have a subdivided shell with a low-stressed, insulative skin. The inner skin would be highly tensed and made from some unobtanium that would have to be impervious to the corrosive effects of water on one side and the embrittlement effects of hydrogen on the other.

The upside is that instead of all the insulation being in a thin outer skin, the heat is inserted into the hydrogen in the inner bag and the steam become a layer of insulation as well. The steam would be at overpressure; so, worst case, the hydrogen might be at ambient pressure. Deeper vacuum = more lift.

Condensing the steam kills lift to facilitate ground handling. If it is designed to ever land.

aerohead 06-02-2014 06:11 PM

think
 
Quote:

Originally Posted by bobdbilder (Post 427461)
What do you think about this from Hybrid Air Vehicle UK. They brought back to UK a working unit that was supposed to see action in Afghanistan with the US military.

http://hybridairvehicles.com/images/range.jpg

Isn't it a successful heavy-lift craft which can perform very efficiently with certain specific tasks?

aerohead 06-02-2014 06:14 PM

wind
 
Quote:

Originally Posted by Old Mechanic (Post 427465)
I always like the idea of an inflatable pedal powered aircraft. Using a lighter than air gas, for inflation, would reduce the effective weight of the plane-pilot combo, but it would probably not be practical in any wind conditions.

regards
Mech

I think Gallagher's attorneys would only allow him to pilot his White Dwarf on a tether.

basjoos 06-02-2014 06:34 PM

Quote:

Originally Posted by Xist (Post 427527)
The idea was that you could exceed the speed of sound without creating a sonic boom if you did not have wings and in order to fly,
:D

Supersonic wingless aircraft do create sonic booms. When the V2's bombarded London in WW11, they produced a characteristic double boom. The first boom was the explosion of the missile when it hit the ground, the second heard boom was the sonic boom created by the missile when it entered the upper atmosphere which lagged behind the missile in reaching the ground. The V2 impacted at about Mach 2.

botsapper 06-02-2014 08:15 PM

I remember when it was tested here, even using an old US Navy blimp hanger. The Aeroscraft 'Dragon Dream', a new gen rigid aluminum-skinned airship prototype with compressed helium-bladder system that controls buoyancy and altitude. Lift off is augmented by turbofan engines and steerable rear props to move it forward. At speed, the aero shape is controlled by front canards and rear empennages. All fly-by-wire signals use fiber optics, immune to EMF interference and unaffected by lightning strikes. It even uses vacuum pods system to anchor it down without the need for an extensive landing crew. https://www.youtube.com/watch?v=t2clnsFvFOs

gone-ot 06-02-2014 10:06 PM

I really liked how they integrated "automatic" bouyancy compensation control for loading/unloading of cargo.

some_other_dave 06-03-2014 03:04 PM

Ouch, that footage is pretty badly damaged...

-soD

freebeard 06-03-2014 07:31 PM

'Dragon Dream' is seriously underpowered, and there are spots on the skin that had been overstressed and stretched already.

I believe the landing gear is hovercraft skirts. Using vacuum to anchor it wouldn't work until it is completely on the ground, if then.

bobdbilder 06-03-2014 11:46 PM

Hav
 
Quote:

Originally Posted by aerohead (Post 427684)
Isn't it a successful heavy-lift craft which can perform very efficiently with certain specific tasks?

Yes, its no longer a concept on a drawing board. Its working. But it gets to the point where great ideas needs to get buying customers. They've made one under contract for the US Military for surveillance, Electronics Warfare and UAV control platform. Something went wrong. They mothballed it and the UK guys just got it back. Donnington I think where they still have a hangar. But that area is under threat of development for housing. If they run out of prospects, the government will push to close their hangar down.

freebeard 06-04-2014 02:41 AM

Maybe they could crowd-source funding to fly it to Tillamook, Oregon.

They just regained control of a NASA satellite that way. Aargh, it be a pirate satellite, now, matey.


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