Author Topic: New Airship Designs  (Read 27478 times)

Offline Hyperion5

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New Airship Designs
« on: 03/31/2016 03:14 am »
In a very exciting bit of news for possible rocket transportation (amidst a sea of other potential uses), Lockheed Martin has signed a 480 million dollar deal to deliver twelve 20-ton capacity hybrid airships to Straight Line Aviation of the UK to help supply remote oil facilities.  Deliveries are slated to being in 2018, with the last airship being delivered in 2021.  Even larger variants up to 500 tonnes in capacity are already on the drawing boards.  Lockheed's LMH-1 design is a heavier-than-air semi-rigid airship (semi-rigid in that it has a structural skeleton but not a rigid outer frame).  It is about a third heavier than air, eliminating the need for ballast and improving ground handling, and also comes with suction pads to enable it to better adhere to the ground in high winds.  It can hover as well land on water (as can just about every new airship design). 

http://www.cnbc.com/2016/03/29/lockheed-has-liftoff-sells-new-airships-in-480m-deal.html

This deal appears to be at the forefront of a resurgence in airship designs and commercial interest worldwide.  In the UK, Hybrid Air Vehicles is about to start comprehensive testing of its 302 ft-long Airlander 10, which will soon be the world's largest aircraft.  It was a hybrid airship previously developed for the Pentagon but almost doomed by budget cuts and a crash.  Although similar to Lockheed's Skunkworks-developed LMH-1, the Airlander has only half its cargo capacity (hence 10).  A 5X as capable variant, the Airlander 50, is already on the drawing boards, and unlike its sibling would be powered by 4 gas turbines, rather than 4 diesel engines, allowing it to possess a much faster cruise speed of 105 knots (195 km/h or 121 mph). 

http://www.hybridairvehicles.com/aircraft/airlander-10

Perhaps the most technologically advanced designs underway are those from Tustin, California's Aeroscraft.  Unlike its competitors, Aeroscraft (formerly World Wide Aeros) finished a rigid hybrid airship, the first built on Earth since 1939, when the Hindenburg's sibling, the LZ 130 Graf Zeppelin II, was finished.  The design was also unique for its COSH system (Control of Static Heaviness), which could vary the airship’s buoyancy like a submarine.  To do this it can compress helium, creating a negative pressure inside the aeroshell, which then allows its air expansion sacs to fill, thus making the vehicle heavier.  This allows the Aeroscraft to off-load payload with ease.  To increase lift, it simply releases the compressed helium, which forces the air out of its expansion sacs, thus making the vehicle lighter-than-air or very nearly.  Although the prototype was scrapped due to a hangar roof collapse damaging it, the firm recently announced a design freeze and beginning production on the smallest production model (the 60-tonne capacity ML866).  http://www.sciencealert.com/production-is-underway-on-the-world-s-largest-aircraft

There are several other firms working on designs, including a firm in Russia, as well as a Canadian firm working on a solar-powered airship design.   I’m sure there are others who I have not remembered, so please let me know if I’ve missed any manufacturers. It’s worth remembering the history of airships to put this in perspective.  Up until the 1930s, airships were prominent in the field of aviation, being the first pilotable aircraft and setting the precedent of being the first aircraft to circle the Eiffel Tower (also first aircraft to bomb London).  They died out in the 1930s, either due to accidents (see America’s flying aircraft carriers, the USS Macon & USS Akron, Britain’s R101, or the Hindenburg), decommissioning (the USS Los Angeles) or the coming of World War II (the Graf Zeppelin II).  When the Zeppelin company was wound down, funds left over were placed in an endowment under the guardianship of the Mayor of Friedrichshafen (the Zeppelin company’s hometown in Germany).  Use of the funds was limited to constructing airships.  By the late 1980s, a half century after the company’s demise, the endowment had grown large enough to seriously consider building a new airship.  The result was the re-born Zeppelin company’s Zeppelin NT semi-rigid airship, which did not fly until 1997 (https://en.wikipedia.org/wiki/Zeppelin_NT).  Recently this design has begun replacing Goodyear’s blimps, thanks to their higher speed, quieter operation, greater range and greater size. 

Since the Zeppelin NT’s flight, there was a slow revival of airships, thanks partly to Pentagon funding of the LEMV (see the Airlander 10) and DARPA’s funding of the Walrus HULA project (see Aeroscraft).  There have also been some false starts, including the bankruptcy of Cargolifter AG.  With the Lockheed deal in place, the future for airships hasn’t looked this bright since the 1930s.  So have fun, sound off on the merits of each firm’s design approach, and let us know what uses you envision for these new airship designs (besides transporting non-volume limited rockets of course). Special dedication to Sanman, who did a great job on the Aeroscraft thread. 
« Last Edit: 03/31/2016 03:16 am by Hyperion5 »

Offline mikelepage

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Re: New Airship Designs
« Reply #1 on: 04/01/2016 04:36 am »
Glad to hear Aeroscraft has gone into production.  I've always thought that if I had the ear of someone feeling particularly philanthropic, it would an amazing project to buy one or more of these and convert them into fully functional trauma hospitals/mobile pathology labs for use in humanitarian disaster relief.  A number of countries have ships in their navies that are set up for such work, but they often have difficulty getting to where they are needed, and many of the high-tech pieces of equipment you really want in such a location (CT scanners/flow cytometers etc) are bulky and tend not to be so robust when moved/vibrated around a lot on planes/ships etc.

As far as space applications go, I imagine the bigger airships would be quite good at moving rockets to launch sites, and could make more viable some of the currently less accessible launch sites - which nonetheless would be useful for accessing a specific (low radiation) orbit like Equatorial LEO.

Offline Aussie_Space_Nut

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Re: New Airship Designs
« Reply #2 on: 04/02/2016 05:17 am »
Yes I think they have tremendous potential. And it seems that there are now a few serious irons in the fire so to speak. So hopefully we will see an economically viable system emerge in the not too distant future. My hunch is that the Aeroscraft has the best chance simply because it lifts 66 tons with a generous size envelope. So long as the airfreighting of ungainly items can carry the costs of the Aeroscraft that is.

So much has been promised over so many years can we see this concept finally succeed?

Well flying wings were a rubbish idea for years, then they built the B2.

RTLS rockets were a rubbish idea, then they built the Falcon 9.

So I hope so!

Offline Hyperion5

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Re: New Airship Designs
« Reply #3 on: 04/04/2016 03:05 am »
Glad to hear Aeroscraft has gone into production.  I've always thought that if I had the ear of someone feeling particularly philanthropic, it would an amazing project to buy one or more of these and convert them into fully functional trauma hospitals/mobile pathology labs for use in humanitarian disaster relief.  A number of countries have ships in their navies that are set up for such work, but they often have difficulty getting to where they are needed, and many of the high-tech pieces of equipment you really want in such a location (CT scanners/flow cytometers etc) are bulky and tend not to be so robust when moved/vibrated around a lot on planes/ships etc.

As far as space applications go, I imagine the bigger airships would be quite good at moving rockets to launch sites, and could make more viable some of the currently less accessible launch sites - which nonetheless would be useful for accessing a specific (low radiation) orbit like Equatorial LEO.

I was checking the dimensions of the proposed ML86X, and it appears that its cargo bay and lifting capacity are more than adequate for lifting a BFR.  Even a 15-meter rocket would have some margin to fit inside.  If I remember right from the Aeroscraft thread, you could alternatively have fit 2 Saturn Vs side-by-side in the internal cargo bay.  The interesting thing to me is, when I have read experts' takes on airships, they often point out that these 'small' airship designs are not ideal.  To be truly economical from a cost-time perspective, airships need to be much larger (lifting 500-1000 tonnes at a time).  The problem is they have to be absolutely enormous to do that, greatly increasing the risk, infrastructure and costs involved.  It will be interesting to see how quickly they scale up from 10-20 tonne cargo lifters to something more economical.  Last I looked every single one of the main 3 competitors so far (Lockheed Martin, Hybrid Air Vehicles and Aeroscraft) had a much larger variant on the drawing board. 

To me the most surprising thing was the 3 different approaches taken by each of the competitors

Lockheed:
Heavier-than-air semi-rigid airship with suction pads & dynamic lift

Hybrid Air Vehicles:
Lighter-than-air semi-rigid airship with dynamic lift, high-altitude ceiling and limited variable buoyancy

Aeroscraft:
Lighter-than-air rigid airship with suction pads and submarine-like variable buoyancy


I personally think Aeroscraft has the best approach, but it's hard to argue that Lockheed has a bad approach after landing a dozen sales.  What I like about the Aeroscraft approach is you can get the superior fuel economy of a more classical airship but still enjoy good ground handling while off-loading.  The catch of course is the added weight of the frame and the helium compression system.  That means a HAV or Lockheed airship is likely to be more capable at the same size. 

Aside from uses on Earth, I'm excited to see this tech return because it augurs well for the possibility of an airship mission to Titan.  Titan of course being the only moon in the solar system with a wonderfully thick atmosphere like the Earth's.  It would require some unique tricks to get the airship to inflate only after Titan atmospheric entry, but the science pay-off would be tremendous.  There has also been some mention of using this approach for Venus scientific missions. 

Offline Hyperion5

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Re: New Airship Designs
« Reply #4 on: 04/04/2016 03:17 am »
Yes I think they have tremendous potential. And it seems that there are now a few serious irons in the fire so to speak. So hopefully we will see an economically viable system emerge in the not too distant future. My hunch is that the Aeroscraft has the best chance simply because it lifts 66 tons with a generous size envelope. So long as the airfreighting of ungainly items can carry the costs of the Aeroscraft that is.

So much has been promised over so many years can we see this concept finally succeed?

Well flying wings were a rubbish idea for years, then they built the B2.

RTLS rockets were a rubbish idea, then they built the Falcon 9.

So I hope so!

The mystery about why it took this long for airships to return.  As near as I can tell it's a combination of the "giggle factor" (nobody into airships is "serious"), drawing the wrong lessons from the Hindenburg photo in every history textbook, the need for buoyancy control tech, and mostly money.  It's worth noting that all three of the main competitors have at one time or another relied on Pentagon funding.  I have my doubts we'd be seeing seeing airships from this many manufacturers if not for the Pentagon. 

Offline savuporo

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Re: New Airship Designs
« Reply #5 on: 04/04/2016 03:22 am »
Having nothing interesting to say, i'll say this is a cool thread and airships are awesome. That said, is there even a theoretical basis or relevant recent trade analysis for making hydrogen in airships usable and safe ?
« Last Edit: 04/04/2016 03:22 am by savuporo »
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Offline mikelepage

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Re: New Airship Designs
« Reply #6 on: 04/04/2016 04:56 am »
Having nothing interesting to say, i'll say this is a cool thread and airships are awesome. That said, is there even a theoretical basis or relevant recent trade analysis for making hydrogen in airships usable and safe ?

IIRC it was never the hydrogen in the Hindenburg that was the problem, but every chemistry student who has ever had a good teacher has seen a hydrogen filled balloon combust with spectacular results, so if you'll forgive the pun, I'm pretty sure hydrogen airships will never get off the ground, helium shortage or no.

Aside from uses on Earth, I'm excited to see this tech return because it augurs well for the possibility of an airship mission to Titan.  Titan of course being the only moon in the solar system with a wonderfully thick atmosphere like the Earth's.  It would require some unique tricks to get the airship to inflate only after Titan atmospheric entry, but the science pay-off would be tremendous.  There has also been some mention of using this approach for Venus scientific missions. 

Agreed, but not sure why you emphasise Titan over Venus.  Science payoff at Venus would be significant too, and far easier to get to Venus than Titan. The way current thin film solar tech is going, you could potentially make use of the airship membrane to harvest the plentiful solar energy at the altitudes where you want to put an airship on Venus too.  Fairly sure the first airships on Titan will have been proved out using tech developed on Venus ;)


Offline QuantumG

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Re: New Airship Designs
« Reply #7 on: 04/04/2016 05:03 am »
IIRC it was never the hydrogen in the Hindenburg that was the problem, but every chemistry student who has ever had a good teacher has seen a hydrogen filled balloon combust with spectacular results, so if you'll forgive the pun, I'm pretty sure hydrogen airships will never get off the ground, helium shortage or no.

The real danger is oxygen and it's everywhere.
Human spaceflight is basically just LARPing now.

Offline MIKKELH

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Re: New Airship Designs
« Reply #8 on: 04/04/2016 09:34 am »
I have always been fascinated by the idea of airships... Almost as mich as spacecraft, and equal to submarines. The only reason I have never really liked blimps is the 'giggle factor' that they are really nothing more than a child's helium filled balloon on steroids. They simply look ugly, and not particularly streamlined (not 'cool' enough). I have the same bias against high altitude helium balloons, unfortunately. One of the features I have always liked about the semi-rigid dirigibles is that they can be sculpted to allow for improved aerodynamic lift.
For a long time now, I have been contemptlating the possibility of developing airships with new features... Or, at least, features that I have never heard of being investigated.
First would be a hot helium airship, or even a hot hydrogen airship with a hot helium outer envelope to protect against possible unwanted ignition. Instead of controlling bouyancy by pumping helium in and out of the helium envelope, the helium envelope would be expanded by heating the helium, thereby allowing for greater lift loads. When the helium is allowed to cool, the helium envelope will deflate, allowing, air to enter. Interestingly, I have seen designs for hybrid balloons with regular helium envelopes surrounded by hot air envelopes, but not for heating helium directly. I understand that heating helium or hydrogen increases the rate of 'tunneling' loss (the escape of gas through an intact envelope), but would this loss be significant enough to outbalance the advantages of a hot gas dirigible?
A second refinement would be a delaminable skin. High altitude balloons are limited by the envelope thickness (and thus mass) required to withstand low level atmospheric forces. One company has proposed staged dirigible to orbit booster systems that would rely on standard helium balloons to achieve a certain altitude, and then transfer the load to another helium balloon with a thinner skin to attain near orbit altitudes. The final stage would then be a low thrust rocket. However, it seems to me that ôe could replace using two balloons with a single balloon with a laminated skin. At low altitudes, the uninflated laminated layer reinforces the primary envelope. There is a simple sheet valve that is arranged in such a way that the internal pressure forces the valve closed. At high altitude, an electric charge would be applied to the two sides of the valve, forcing the sheet to lift away and open. This would allow the laminated layer to inflate. The laminating layer would include accordian side walls. This system would allow for much oncreased volume with thinner walls, increasing lift performance. If necessary, you could stack laminated layers. Ideally, this system could be combined with the hot gas design. The system would only work with semi-rigid airships.
A third concept would be a variation of the previous, incorporating an infaltable wing that could make use of aerodynamic lift. Even at  LEO altitudes, there is a little bit of atmosphere, so it seems to me that sufficient speeds at suborbital altitudes should provide non-negligible lift for lighter than air craft. Alternatively, the airship itself could be configured with a glider wing design, and the delaminated envelopes could maintain that design, increasing the chord of the 'wing'.
Finally, a question... If any of these variations work, and lead to a super high altitude airship capable of lifting useful payload masses, would it be conceivable for such an airship to achieve an altitude where an ion engine would provide sufficient thrust to slowly accelerate the airship to orbit?

Offline mikelepage

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Re: New Airship Designs
« Reply #9 on: 04/04/2016 01:33 pm »
Finally, a question... If any of these variations work, and lead to a super high altitude airship capable of lifting useful payload masses, would it be conceivable for such an airship to achieve an altitude where an ion engine would provide sufficient thrust to slowly accelerate the airship to orbit?

I'll jump in before someone else comes in and stomps on your ideas less kindly.  I used to wonder about this, then someone in this forum explained to me why any and all the ideas about using some non-rocket form of propulsion to get you part of the way up aren't worth much if any effort.

Long story short, it's velocity that matters, not altitude.  Say we're very generous and your airship gets you to 70-80km altitude... you're still stationary, and you still have to get to >7.7km/s, and you've gone to an extraordinary amount of work to save yourself <10% the mass of the rocket.  The falcon 9 gets through that distance in less than a minute out of the 8 minutes it spends to get itself to orbit. 

And re ion engine: If I'm not wrong, you would basically need a balloon/space elevator to get you to near geostationary orbit (35,000km) before an ion engine would have enough kick to get you into orbit before you crashed to the ground.

Offline MIKKELH

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Re: New Airship Designs
« Reply #10 on: 04/04/2016 07:29 pm »
Yes, I am quite aware for the need for velocity to actually achieve orbit, although there might be some benefits just to having an extremely high altitude platform for suborbital missions (telescopic obvservation platforms, for instance, that do not necessarily have to go in orbit, they just have to get above the majority of atmospheric interference for extended durations). My primary interest is to determine if such approaches would be feasible for obtaining extremely high (sub orbital) altitudes beyond what is currently achievable, or if there is a flaw that would prevent these approaches from working... Such as if the lifting gas loss of the hot gas envelope would be too high.
As for booster applications, if one of these methods, or a combination thereof, could lift a significant load to a high enough altitude, then a more conventional booster could take over (following separation, of course), increasing altitude and providing the necessary lateral velocity for orbit. The benefit is that you would require much less propellant, the rocket would benefit from virtually full vacuum thrust and Isp, and the rocket stage would not have to fight against sognificant atmospheric drag. For reference, the Saturn V first stage only propelled the apollo spacecraft to an altitude of 36 miles. This is comparable to the 50km+ altitudes already achieved by some helium balloons. Thus, if these systems could lift the remaining stages of a Saturn V to the same altitude, you save a considerable amount of propellant... Just think of the advantage it could provide rocket boosters only meant to lift modest payloads to LEO. Such a drop launch would not be new... The technique has been used for the x-1, x-15, and numerous lifting bodies.
As for ion engines... They have been used to propell quite a number of satellites from LEO to geostationary orbit, and are also used frequently for maintaining LEO. I believe they have been successfully used to boost the ISS to higher orbits for its LEO corrections. Once in an orbit, no matter how low, ion thrusters are sufficient to lift satellites into orbits as high as they have sufficient propellant for... It just takes a really long time. Now, there is no question of the airships crashîg to the ground, so long as the envelopes remain intact, so there would be plenty of time for an ion thruster to slowly accelerate the airship to sufficient velocities. However, I do not know offhand if such thrusters would be able to overcome even what little atmospheric drag exists at such high altitudes.

Offline savuporo

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Re: New Airship Designs
« Reply #11 on: 04/04/2016 07:36 pm »
Yes, I am quite aware for the need for velocity to actually achieve orbit, although there might be some benefits just to having an extremely high altitude platform for suborbital missions (telescopic obvservation platforms, for instance, that do not necessarily have to go in orbit, they just have to get above the majority of atmospheric interference for extended durations).
JP Aerospace is known for building these kind of things, see http://www.jpaerospace.com/ascender175.html

http://www.jpaerospace.com/atohandout.pdf
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Offline sevenperforce

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Re: New Airship Designs
« Reply #12 on: 04/04/2016 08:04 pm »
Once in an orbit, no matter how low, ion thrusters are sufficient to lift satellites into orbits as high as they have sufficient propellant for... It just takes a really long time. Now, there is no question of the airships crashîg to the ground, so long as the envelopes remain intact, so there would be plenty of time for an ion thruster to slowly accelerate the airship to sufficient velocities. However, I do not know offhand if such thrusters would be able to overcome even what little atmospheric drag exists at such high altitudes.
Like mikelepage, I don't want to stomp, but...unfortunately, no. Pretty much by definition, an airship which depends on buoyancy to stay aloft will have too much aerodynamic drag to be accelerated to orbital velocities. Buoyancy depends on displacing air, displacing air requires volume, volume requires surface area.

Offline mikelepage

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Re: New Airship Designs
« Reply #13 on: 04/05/2016 11:52 am »
The benefit is that you would require much less propellant, the rocket would benefit from virtually full vacuum thrust and Isp, and the rocket stage would not have to fight against sognificant atmospheric drag. For reference, the Saturn V first stage only propelled the apollo spacecraft to an altitude of 36 miles. This is comparable to the 50km+ altitudes already achieved by some helium balloons.

Yeah, not so much.  I read somewhere that someone calculated the figure at about 2-3% propellent savings by launching from high-altitude balloon.  It feels like it should be bigger, until you really grok how little the starting altitude matters (0-100km) in comparison to the 40,000 km circumference of the Earth that the rocket has to get around.

Put it another way, how fast do you think the Saturn V was going at 36 miles when it performed stage separation? Quick search gives me 750 metric tons (empty first stage plus full upper stages) travelling at 3 km/s which works out to ~3.4 TJ of Kinetic energy (about 1/20th the energy of the Hiroshima bomb).  Your airship infrastructure has to save you at least that much energy for it to be more efficient to start from that high up (instead of just using a first stage).

Given that you need 22.4 litres of Helium to lift ~25 grams of payload (at sea level pressure - that ratio will only get worse as you go up), any airship hoisting a fully fueled rocket (as opposed to transporting an empty stage - which is what I was talking about earlier), is going to need to be far bigger than anything on the foreseeable horizon.  Hopefully we'll have solved this problem by the time we're trying to launch rockets from cloud cities on Venus.

To address your first point last, a lightweight high altitude telescope could be interesting, but I think the advances in adaptive optics may have swung the cost-benefit back in favour of ground telescopes, worth checking out.

Offline pippin

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Re: New Airship Designs
« Reply #14 on: 04/05/2016 05:30 pm »
Hm I assume you all have seen the Airlander crowdfunding?
https://www.crowdcube.com/invest-now/hybrid-air-vehicles-20925

I can't help myself, I smell Cargolifter all over again.

Offline spacenut

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Re: New Airship Designs
« Reply #15 on: 04/05/2016 05:45 pm »
I think airships would be great for heavy hauling into tight places, or short runways.  They can carry way more than a helicopter or even a VTOL aircraft.  The problem is wind and weather, and good control when landing/mooring.  Bad winds or bad weather can be avoided or would delay a cargo shipment until it passed.  Massive amounts of non-perishable food, military gear, etc could be delivered faster than a ship to areas not accessible to large cargo planes.  And as some said, could deliver a 15m diameter BFR, or even multiple 5.2m Raptor upper stages for the Falcon 9 or Falcon Heavy. 

Offline pippin

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Re: New Airship Designs
« Reply #16 on: 04/05/2016 05:57 pm »
Have you read the financials of that pitch? Yet still people seem to be throwing money at them like crazy.
It's the same thing as it was with Cargolifter and with Zeppelin NT... The one thing these machines have always been really good at is combusting money like rocket engines burn fuel.
« Last Edit: 04/05/2016 05:59 pm by pippin »

Offline MIKKELH

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Re: New Airship Designs
« Reply #17 on: 04/05/2016 08:39 pm »
Once in an orbit, no matter how low, ion thrusters are sufficient to lift satellites into orbits as high as they have sufficient propellant for... It just takes a really long time. Now, there is no question of the airships crashîg to the ground, so long as the envelopes remain intact, so there would be plenty of time for an ion thruster to slowly accelerate the airship to sufficient velocities. However, I do not know offhand if such thrusters would be able to overcome even what little atmospheric drag exists at such high altitudes.
Like mikelepage, I don't want to stomp, but...unfortunately, no. Pretty much by definition, an airship which depends on buoyancy to stay aloft will have too much aerodynamic drag to be accelerated to orbital velocities. Buoyancy depends on displacing air, displacing air requires volume, volume requires surface area.
True. However, surface area does not have to be uniform, and the bulk of the drag will be dependent upon the area cross section, which can be minimised. Granted, I have my own doubts that an ion drive would be sufficient, but how much drag are we likely to be talking about? At which altitude would an ion drive start to become useful?

Offline knowles2

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Re: New Airship Designs
« Reply #18 on: 04/05/2016 10:22 pm »
Glad to hear Aeroscraft has gone into production.  I've always thought that if I had the ear of someone feeling particularly philanthropic, it would an amazing project to buy one or more of these and convert them into fully functional trauma hospitals/mobile pathology labs for use in humanitarian disaster relief.  A number of countries have ships in their navies that are set up for such work, but they often have difficulty getting to where they are needed, and many of the high-tech pieces of equipment you really want in such a location (CT scanners/flow cytometers etc) are bulky and tend not to be so robust when moved/vibrated around a lot on planes/ships etc.

As far as space applications go, I imagine the bigger airships would be quite good at moving rockets to launch sites, and could make more viable some of the currently less accessible launch sites - which nonetheless would be useful for accessing a specific (low radiation) orbit like Equatorial LEO.
Hybrid Air Vehicles have apparently already received interests from UN humanitarians organisations. Not sure if they could afford to actually buy one or few of these out right through, but leasing time on one is more than a probability.

There no shortage of ideas for how these will be use, The British Mod will this year be using this Hybrid air Vehicle Airlander prototype to test a surveillance systems. The team behind it has stated they excited just for the amount of gear they will be able to stick on it and that they won't have to make compromises to reduce weight.

Have you read the financials of that pitch? Yet still people seem to be throwing money at them like crazy.
It's the same thing as it was with Cargolifter and with Zeppelin NT... The one thing these machines have always been really good at is combusting money like rocket engines burn fuel.

I think this time they have at least one key market that will at least return some money to investors, long term, as in months surveillance systems, which could be the key to defeating the likes of the Taliban and ISIS IEDs.

Not a big market but could provide the sales to keep a small company like HAV alive, this is where I think Hybrid Air Vehicles has a huge advantage over the competition, the development costs have largely been absorbed by the US military,  so I believe the vehicle will end up being the cheapest on the market and why the military aren't facing the cut backs they were, politicians still want to get value for money.


I personally think Aeroscraft has the best approach, but it's hard to argue that Lockheed has a bad approach after landing a dozen sales.  What I like about the Aeroscraft approach is you can get the superior fuel economy of a more classical airship but still enjoy good ground handling while off-loading.  The catch of course is the added weight of the frame and the helium compression system.  That means a HAV or Lockheed airship is likely to be more capable at the same size. 

They only have a letter of intent, which could be withdrawn at any time.
« Last Edit: 04/05/2016 10:41 pm by knowles2 »

Offline pippin

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Re: New Airship Designs
« Reply #19 on: 04/05/2016 11:36 pm »
Not a big market but could provide the sales to keep a small company like HAV alive, this is where I think Hybrid Air Vehicles has a huge advantage over the competition, the development costs have largely been absorbed by the US military,  so I believe the vehicle will end up being the cheapest on the market and why the military aren't facing the cut backs they were, politicians still want to get value for money.

The usual fallacy. Having less development costs (or them covered) makes your business case easier and is good for investors but it doesn't make your craft any cheaper.
It's just easier to make a profit (as in: faster) but if your craft loses money on each one built you are still going out of business.

And the hard part only starts for them, getting this thing operational.

People tend to dramatically overestimate the impact of early stage development costs. In reality, most of your costs only arise after you are done testing your prototype.

 

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