Why don't they fill airplanes with helium?
zalzon
bomber. So i was wondering, why don't design airplanes that are filled
with highly pressurized helium? That should make it much easier taking
off. The entire flight would also require less fuel, even the landing.
The plane might also be able to carry a heavier load.
It sounds to me like the perfect match - blimps and planes.
Dave Kearton
"zalzon" <zalzon...@zalll.com> wrote in message
news:pan.2004.07.22....@zalll.com...
The aircrews would revolt if they had to talk with those high, squeaky
voices.
Cheers
Dave Kearton
Krztalizer
and there isn't as much of it as you may think.
v/r
Gordon
<====(A+C====>
USN SAR
Its always better to lose -an- engine, not -the- engine.
Thomas Schoene
> A lot of energy is expended getting off the ground for an airplane
> like a bomber. So i was wondering, why don't design airplanes that
> are filled with highly pressurized helium? That should make it much
> easier taking off. The entire flight would also require less fuel,
> even the landing. The plane might also be able to carry a heavier
> load.
Let's start with some basic physics. The more you pressurize a lifting gas,
the less useful it is (higher pressure => greater density => less buoyancy).
Indeed, the ideal lifting gas would be a hard vacuum, which is obviously
somewhat impractical.
The benefit of what you propose is surely pretty marginal, if it exists at
all. Planes don't generally have huge empty void spaces that they could
fill, and any large unfilled spaces not needed for something requiring
oxygen (i.e., passenger compartments) are generally not sealed, so that
pressure changes don't cause structural damage. Small void spaces might be
sealed and filled, but would return almost no net lift. It takes huge
volumes of helium to lift even modest paylaods.
--
Tom Schoene Replace "invalid" with "net" to e-mail
"Our country, right or wrong. When right, to be kept right, when
wrong to be put right." - Senator Carl Schurz, 1872
Greasy Rider
proclaimed:
I mix helium with my lawn fertilizer. In the fall when everybody in my
neighborhood is raking leaves mine simply float away.
Steve Mellenthin
Planes also have to carry cargo, passengers, and fuel. Not a lot of room for
enough helium to make a difference.
Steven P. McNicoll
Okay. I'll play. Highly pressurized helium is heavier than air. That's
why helium cylinders don't float away.
Brett
One of the space launcher configurations in the X prize competition
(Canada's Da Vinci Project) is based upon a balloon carrying the manned
spacecraft to 24,000 meters before the vehicles engines are fired.
Evan Williams
"Brett" <Br...@192.168.10.1> wrote in message
news:JZYLc.8661$QO....@bignews5.bellsouth.net...
That is true, but it only goes up and down. Not from LA to NYC
Evan Williams
Regnirps
news:pan.2004.07.22....@zalll.com...
>
> A lot of energy is expended getting off the ground for an airplane like a
> bomber. So i was wondering, why don't design airplanes that are filled
> with highly pressurized helium? That should make it much easier taking
> off. The entire flight would also require less fuel, even the landing.
> The plane might also be able to carry a heavier load.
>
> It sounds to me like the perfect match - blimps and planes.
I prefer to just use helium paint.
As for your idea, hydrogen is quite a bit lighter, and don't pressurize it.
DC-3's are still flying because they are not pressurized. Why not give pressure
suits to pax and crew and avoid stressing the structure?
-- Charlie Springer
Eunometic
> zalzon wrote:
> > A lot of energy is expended getting off the ground for an airplane
> > like a bomber. So i was wondering, why don't design airplanes that
> > are filled with highly pressurized helium? That should make it much
> > easier taking off. The entire flight would also require less fuel,
> > even the landing. The plane might also be able to carry a heavier
> > load.
>
> Let's start with some basic physics. The more you pressurize a lifting gas,
> the less useful it is (higher pressure => greater density => less buoyancy).
> Indeed, the ideal lifting gas would be a hard vacuum, which is obviously
> somewhat impractical.
You are of course correct.
You would get about 1.2kg lifting force per cubic meter. Given a
B747's fueselage diameter of about 6m and lenght of just over 60m that
would at best give us 1800 cubic meter for a lifting force of about 2
tons. That is pretty negligable in an aircraft with a Maximum takeoff
weight of nearly 400 tons.
That is not to say that hybrid lifting body dirigible/zepplins could
not be made and would not posses advantages.
Also, although pressurisation increases the density of a gas Helium is
so light pressurising it to two atmospheres would not decrease lifting
force more than 10%.
The Atlas missile had its structure stabalised by pressure.
A lightweight vehicle could have its wings and fueselage pressurised
to keep them in tension and to keep them from buckling.
>
> The benefit of what you propose is surely pretty marginal, if it exists at
> all. Planes don't generally have huge empty void spaces that they could
> fill, and any large unfilled spaces not needed for something requiring
> oxygen (i.e., passenger compartments) are generally not sealed, so that
> pressure changes don't cause structural damage. Small void spaces might be
> sealed and filled, but would return almost no net lift. It takes huge
> volumes of helium to lift even modest paylaods.
Hybrids are surely possible. For instance a lenticular lifting body
vehicle that uses rotating X22 osprey type blades to lift itself and a
load in combination with the helium and then uses forward motion to
provide lift aerodynamic lift as the lift blades convert to propulsion
blades.
Eunometic
> Helium = $$$$$$$$$$$$$$$$$$$$
>
>
> and there isn't as much of it as you may think.
Most of it (helium) seems to come out of Natural Gas deposites, for
some reason located mainly in the USA, where it accumulates due to
radioactive decay. Helium is afterall simply an alpha particle that
has grabed some electrons from somewhere else.
Helium can be extracted from the atmosphere but that is expensive.
Maybe the Germans were forced to do so in the second world war? It
was considered a stratgic material by the USA for some reason,
presumably that it might be used for military blimps or long range
strategic bombing of the USA or something.
Interestingly the other noble gases Argon (1% of the atmosphere) and
Xenon (much less) are both lighter than air and can and are extracted
by crygenic seperation from air in commercial quantities. Whereas
Helium should generate about 1.040 kg lifting force per cubic meter
Argon should manage 0.6kg.
The Germans had great success in developing safe opperation of
Zepplins as the Graf Zepplin showed. Had Helium been available to
them the future of the airship may have been a little brighter.
(Admitedly investigation from the NASA guy who designed the Space
Shuttle tank showed that it was the nitrate and aluminium impregnated
and doped Hindenbergs fabric envelope that burned and NOT the
Hydrogen. I've seen hydrogen burn before (invisible or light blue)
and always wandered why there were so many flames on the Hindenberg:
the orthodoxy was so strong I never questioned it further.
Incidently there is one other gas lighter than air: steam. (molecular
weight of water is 18 compared to air of about average 29 and when hot
it is even less dense) A few people (on the web) have been trying to
develop steam bouyant airships using engine waste heat and special
insulating envelope.
Keith Willshaw
Its sounds like a very silly idea if for no other reason than an
aiframe strong enough to hold higly pressurused helium
would have to weigh so much the thing would never leave the ground.
Keith
Keith Willshaw
"Eunometic" <euno...@yahoo.com.au> wrote in message
news:e935396a.04072...@posting.google.com...
> vehicle that uses rotating X22 osprey type blades to lift itself and a
> load in combination with the helium and then uses forward motion to
> provide lift aerodynamic lift as the lift blades convert to propulsion
> blades.
Its been done, take a look at the Skyships range of blimps.
They use rotatble ducted fans and the envelope provides
lift when in forward motion.
Keith
Brett
The flight plan has the vehicle with a downrange flight distance based on
launch angle after the rocket engines burn out (see figure 11 in the
follwoing pdf).
http://www.davinciproject.com/beta/EADSpaper_n39_2.pdf
> Not from LA to NYC
So you go UP at LA and DOWN at NYC
John Cook
Its not as crazy as it sounds, if you were to build a B2 (ish) shaped
blimp with a bit of a stiffer exterior so it keeps its shape, you
would get a highly manouvarable airframe with some potentially
excellent steath potential, add in ducted fan engines and you may end
up with an aircraft like that one reported in the UK.
A large black triangle that can fly slow, silent and low and turn on a
sixpence!!.
Just speculation!!!! ;-)
Cheers
John Cook
Any spelling mistakes/grammatic errors are there purely to annoy. All
opinions are mine, not TAFE's however much they beg me for them.
Email Address :- Jwcook@(trousers)ozemail.com.au
Spam trap - please remove (trousers) to email me
Eurofighter Website :- http://www.eurofighter-typhoon.co.uk
Keith Willshaw
"John Cook" <Jwc...@ozemail.com.au> wrote in message
news:reu1g0d7mlc00bgah...@4ax.com...
> On Thu, 22 Jul 2004 23:13:47 GMT, zalzon <zalzon...@zalll.com>
> wrote:
>
> >A lot of energy is expended getting off the ground for an airplane like a
> >bomber. So i was wondering, why don't design airplanes that are filled
> >with highly pressurized helium? That should make it much easier taking
> >off. The entire flight would also require less fuel, even the landing.
> >The plane might also be able to carry a heavier load.
> >
> >It sounds to me like the perfect match - blimps and planes.
>
>
> Its not as crazy as it sounds, if you were to build a B2 (ish) shaped
> blimp with a bit of a stiffer exterior so it keeps its shape, you
Would get an unstable shape that was too heavy to rise
by buoyancy alone. An airship envelope needs to enclose
maximum volume with minimum weight. This requirement
is not compatible with being B-2 shaped
> would get a highly manouvarable airframe with some potentially
> excellent steath potential, add in ducted fan engines and you may end
> up with an aircraft like that one reported in the UK.
>
The G pulled by a combat aircraft is a function of
speed and turn radius and radar reflects very nicely
off ducted fans, wiring and the cockpit internals
> A large black triangle that can fly slow, silent and low and turn on a
> sixpence!!.
>
But with no payload carrying capacity to speak of
> Just speculation!!!! ;-)
>
And militarily useless.
Keith
Evan Williams
would be be at the mercy of the wind while hauling cargo/people from point A
to point B and eventually making it back to point A to do it again. BTW did
I read fig.11 correctly? It calls for a horizontal distance of 200 km? If
so, using both balloon and rockets, you wouldn't even make it out of
California.
Evan Williams
W. D. Allen Sr.
helium, bags, aero covering, framework, gondola, engines, wheels, etc off
the ground.
Now imagine how much more helium at the same pressure would be needed to
provide a modicum of assistance in getting off the ground for an airplane.
Wouldn't you expect a truly huge blimp needed to lift that airplane?
WDA
end
"Krztalizer" <krzta...@aol.comint> wrote in message
news:20040722193927...@mb-m20.aol.com...
Brett
Which corresponds to the flight profile demanded for the manned rocket
vehicle to win the X prize. The initial comment was about eliminating the
weight penalties associated with the typical flight profile, taxi, takoff
run and climb to altitude - a helium balloon carrying a conventional
aircraft design to 40,000+ feet and then releasing it would eliminate the
need for the aircraft to carry fuel to cover taxi, takeoff and climb to
cruising altitude (you should also need to use less powerful engines). The
X-1,X-2.....X-15 all used a mother ship to get them to altitude prior to
them being released, the da Vinci Project uses a mother balloon instead of a
mother ship based upon a B-29 or B-52.
Richard Brooks
Because they're thinking of using the Ziotron death ray which doesn't work
too well with helium especially on Galaxion IV!
Richard.
Dave Kearton
news:cds9m4$hkk$1...@news8.svr.pol.co.uk...
Galaxion IV was neutralised at the end of the Zircon Wars. Michael
Moore is making a movie about it (that's the blimp connection).
Cheers
Dave Kearton
B2431
>Date: 7/23/2004 3:25 PM Central Daylight Time
>Message-id: <ZrSdneMSCtC...@adelphia.com>
>
>Consider the weight of helium commonly used in blimps to lift the weight of
>helium, bags, aero covering, framework, gondola, engines, wheels, etc off
>the ground.
>
>Now imagine how much more helium at the same pressure would be needed to
>provide a modicum of assistance in getting off the ground for an airplane.
>Wouldn't you expect a truly huge blimp needed to lift that airplane?
>
>WDA
>
lift a relatively light, compared to modern transports, airship. Helium is
heavier, but you get the idea.
Dan, U. S. Air Force, retired
Regnirps
>Because they're thinking of using the Ziotron death ray which doesn't work
>too well with helium especially on Galaxion IV!
But at the hybrid speeds you simply grapple and the Air Pirates leap from ship
to ship.
Oh, noticed the .uk I have been seeing ads for a live human movie of
"Thunderbirds Are Go!" I wonder who will play the princess?
-- Charlie Springer
Fred the Red Shirt
>
>
> As for your idea, hydrogen is quite a bit lighter, and don't pressurize it.
> DC-3's are still flying because they are not pressurized. Why not give pressure
> suits to pax and crew and avoid stressing the structure?
>
>
Yes, hydrogen is just about half the density of helium, but buoyancy is
determined by the differency in density between the lifting gas and the
ambient atmosphere, not the ratio.
So at sea level hydrogen gives you a bit less than 8% more buoyancy
than helium, despite being half as dense.
To maximize lift what you need is an extremely high strength to
weight pressure vessel. Just evacuate it and float away. Still
less than 16% of an improvement over helium though.
--
FF
Richard Brooks
I can't remember a princess. Look out for 'No Strings Attached: The Making
of Thunderbirds' . We just got to see it today (Saturday).
I've just remembered about the danger of any leakage of helium into the
cabin regarding the helium.
ATC: "Hey guys, listen to this. There are a couple of chipmunks calling
mayday!"
Richard.
Peter Stickney
"Richard Brooks" <richar...@kdbanglia.freeserve.co.uk> writes:
> Regnirps wrote:
>> "Richard Brooks" richar...@kdbanglia.freeserve.co.uk wrote:
>>
>>> Because they're thinking of using the Ziotron death ray which
>>> doesn't work too well with helium especially on Galaxion IV!
>>
>> But at the hybrid speeds you simply grapple and the Air Pirates leap
>> from ship to ship.
>>
>> Oh, noticed the .uk I have been seeing ads for a live human movie of
>> "Thunderbirds Are Go!" I wonder who will play the princess?
>>
>> -- Charlie Springer
>
> I can't remember a princess. Look out for 'No Strings Attached: The Making
> of Thunderbirds' . We just got to see it today (Saturday).
I suspect that he means Lady Penelope Ceighton-Ward.
In any event, it's Sophia Miles.
--
Pete Stickney
A strong conviction that something must be done is the parent of many
bad measures. -- Daniel Webster
Richard Brooks
> In article <cdv70r$mja$1...@news8.svr.pol.co.uk>,
> "Richard Brooks" <richar...@kdbanglia.freeserve.co.uk> writes:
>> Regnirps wrote:
>>> "Richard Brooks" richar...@kdbanglia.freeserve.co.uk wrote:
>>>
>>>> Because they're thinking of using the Ziotron death ray which
>>>> doesn't work too well with helium especially on Galaxion IV!
>>>
>>> But at the hybrid speeds you simply grapple and the Air Pirates leap
>>> from ship to ship.
>>>
>>> Oh, noticed the .uk I have been seeing ads for a live human movie
>>> of "Thunderbirds Are Go!" I wonder who will play the princess?
>>>
>>> -- Charlie Springer
>>
>> I can't remember a princess. Look out for 'No Strings Attached: The
>> Making of Thunderbirds' . We just got to see it today (Saturday).
>
> I suspect that he means Lady Penelope Ceighton-Ward.
>
> In any event, it's Sophia Miles.
Blimey! I didn't know she had a surname. It had to be double-barreled
though.
As to the princess, I thought there migt have been an episode with a
princess in somewhere so didn't question it.
What's next for the new film treatment: Stingray, Supercar or Fireball XL5 ?
Richard.
windeagl...@gmail.com
SolomonW
> I agree, but then everything that flies should have either hydrogen or helium for the fuel savings advantage.
A lot of money has been spent on developing hydrogen planes with limited
success. Hydrogen planes need a much larger fuel tanks and have a higher
operating cost. Currently it is very experimental.
Jim Wilkins
news:38aeac2d-e95e-4efc...@googlegroups.com...
>or helium for the fuel savings advantage.
strong enough to safely contain the gas as it tries to expand at high
altitude.
https://www.avs.org/AVS/files/c7/c7edaedb-95b2-438f-adfb-36de54f87b9e.pdf
At airliner cruising altitude the air pressure outside the tank is
only 1/4 of the sea level (or greater) pressure within the tank.
If gas leaks out up there its containing space (the wing?) will be
crushed when the plane descends to land.