Airships to orbit?

This is s proposed system that should be able to carry payloads on low orbit. It was envisioned by JP Aerospace and it has three stage design.
First one is large amospheric (conventional) airship able to lift the payloads to the 30-40km. the second is docking station acting as resuply station for 3rd stage - Orbital Ascender able to take payloads to the orbit via the combination of helium filled blimp and ion engines.
I suppose in sufficient altitude only the inon engines are used. The whole ascent takes 3-9 days which means only the unmanned payloads (such as satelites or supplies could be used).

he 3 stages are because the conventional airship able to withstand weather effects in lower atmosphere is too heavy, so the 3rd stage must have thinner walls.
What do you think could it work? It sounds difficult for me to project the airship able to reach 100km alt, but if it works the lift-to-orbit costs could become much lower 1$ per mile and ton.

en.wikipedia.org...

Wouldnt an airship just burst under the pressure on its way to orbit?

Heres a good site on what you talking about.
Airships

and yes, I think it could work.
and I would love to see a massive Airship over a mile long.

[edit on 2-6-2005 by Murcielago]

I like the idea, cheap and enviromentaly sound. Can be done with todays technology.

Better link: /www.jpaerospace.com

Better idea: www.t/space.com

Some UFOlogists believe that this is what the mysterious 'Big Black Triangles' really are... either an extremely high altitude airship or an airship that can launch things into space from high altitude.

Originally posted by onlyinmydreams



Some UFOlogists believe that this is what the mysterious 'Big Black Triangles' really are... either an extremely high altitude airship or an airship that can launch things into space from high altitude.

Oddly enough, our initial research and development phase was funded by the USAF Space Command BattleLab, through a third party government contractor (nameless) which had handled a number of "Black Budget" projects.

And the military is still very interested in persuing the project.

I often wondered if our participation was so valued by the USAF for the "cover story" our Ascender could provide for more "exotic" vehicles they might be prototyping.

And no, "Popping" is NOT a problem. There are materials currently available which can easily endure the pressure generated by the vaccuum of space.

The first US sattalite ECHO I was nothing more then a big ballon to bounce radio waves off of. Not to metion the first man made object in space that was easily visible to the naked eye

IMHO Helium is rather expensive to use. .comapred to hydrogen. But I guess it is better then propellent, and is a lot safer then either

You might have wanted to read the following part in the wikipedia link you provided:

Several prominent posters on the sci.space Usenet groups, of which many knowledgeable amateur, and some professional, rocketry and space enthusiasts discuss such technologies, remain highly sceptical of JP Aerospace's claims. They believe that existing propulsion technologies for the airship are heavy enough, and the lift-to-drag ratios of lifting bodies at hypersonic speed poor enough, that without a fundamental breakthrough in one or both of these areas, there is no way the craft will be able to accelerate itself to orbital velocity and gain sufficient altitude. Their consensus is that either the company has made a mistake, or that their plans revealed to date omit some vital technical point.

JP Aerospace's design proposal was found to be technically flawed in an independent analysis by Robert Pickar. Specifically, the design assumes that electric propulsion, powered by solar cells, are sufficient to power the vehicle into orbit. In fact, the thrust generated by electric propulsion is insufficient to overcome atmospheric drag. Thus, the ATO craft would not accelerate beyond a low velocity. This is not a matter of technology, it is a matter of fundamental physics.

Electric propulsion is inherently power-limited, that is, the thrust generated by an electric rocket engine is limited by the power of the electric power source supplying it. Given the intensity of sunlight on solar cells (the solar constant), there is a finite amount of electric power that can be generated. For ATO, this would amount to some 10 MWe. Electric rocket engines can produce about 25 Newtons (6 lbs.) per MWe of power. Thus, a maximum of 60 lbs or so of thrust could be produced. Atmospheric drag on the ATO vehicle comes to about 11,000 Newtons (2,500 lbs). The thrust is far lower than atmospheric drag, and the vehicle will not accelerate.

Additionally, the ATO vehicle would have power cut off during the night. JP Aerospace claimed that this would be handled with regenerative fuel cells. However, regenerative fuel cell systems have a specific mass of 600 W/kg. Replacing the solar cell power with fuel cell power would result in a very large fuel cell. The system would be 100 times the vehicle mass itself.

These are all reasons why the ATO concept is unworkable from the physics standpoint, not just technology that might change in the future.

It's simply not possible, not just because of current technology but because of basic physics and that should end the discussion.

Originally posted by Simon666
You might have wanted to read the following part in the wikipedia link you provided:

Several prominent posters on the sci.space Usenet groups, of which many knowledgeable amateur, and some professional, rocketry and space enthusiasts discuss such technologies, remain highly sceptical of JP Aerospace's claims. They believe that existing propulsion technologies for the airship are heavy enough, and the lift-to-drag ratios of lifting bodies at hypersonic speed poor enough, that without a fundamental breakthrough in one or both of these areas, there is no way the craft will be able to accelerate itself to orbital velocity and gain sufficient altitude. Their consensus is that either the company has made a mistake, or that their plans revealed to date omit some vital technical point.

JP Aerospace's design proposal was found to be technically flawed in an independent analysis by Robert Pickar. Specifically, the design assumes that electric propulsion, powered by solar cells, are sufficient to power the vehicle into orbit. In fact, the thrust generated by electric propulsion is insufficient to overcome atmospheric drag. Thus, the ATO craft would not accelerate beyond a low velocity. This is not a matter of technology, it is a matter of fundamental physics.

Electric propulsion is inherently power-limited, that is, the thrust generated by an electric rocket engine is limited by the power of the electric power source supplying it. Given the intensity of sunlight on solar cells (the solar constant), there is a finite amount of electric power that can be generated. For ATO, this would amount to some 10 MWe. Electric rocket engines can produce about 25 Newtons (6 lbs.) per MWe of power. Thus, a maximum of 60 lbs or so of thrust could be produced. Atmospheric drag on the ATO vehicle comes to about 11,000 Newtons (2,500 lbs). The thrust is far lower than atmospheric drag, and the vehicle will not accelerate.

Additionally, the ATO vehicle would have power cut off during the night. JP Aerospace claimed that this would be handled with regenerative fuel cells. However, regenerative fuel cell systems have a specific mass of 600 W/kg. Replacing the solar cell power with fuel cell power would result in a very large fuel cell. The system would be 100 times the vehicle mass itself.

These are all reasons why the ATO concept is unworkable from the physics standpoint, not just technology that might change in the future.

It's simply not possible, not just because of current technology but because of basic physics and that should end the discussion.

Hmmm, can it be that they in fact want to use some kind of nuclear reactor (radioisotope thermic generator) but they don't want talk about it openly, because of enviromental reasons? They can use it for various purposes, not only for ion porpulsion, but also to heat helium/hydrogen (blimp filled with heated gas is capable to rech higher altitude).
Also to the previous poster - IMO it can use the hydrogen instead of helium, because it would be used for cargo not for people transport - and hydrogen is not that dangerous, it was used by Germans for people transports too.

Even with a RTG, your thrust would still be pretty small if you use electric engines, not to mention yet that that would also weigh a lot if not more. Considering using hydrogen for airships at that altitude, I wouldn't know for sure. At very low pressures, gasses tend to disassociate a lot and atomic hydrogen is just as atomic oxygen pretty reactive. It is also a very small atom/molecule and might perhaps more easily diffuse through the hull, though I wouldn't know how it relates to helium. I would rather suspect that it is a cover for funding black projects instead, it raises less questions than overly expensive hammers and toilet seats.

simon666

USing airships is for the first stage of the design, similar to some of the proposed X-prizes craft of getting the orbiter up high into the atmosphere and beyond Max-Q

No one if suggesting that a derigible would be able to achive escape velocity., either structually or with enough thrust to make a lighter then air boby wothwhile.

Moderan fighter jets can be used to launch sattillite killer missiles., yet the moderan jet really has no chance of attaining orbit itself (excluding the Aurora)

So it is just for the first stage and noone suggests a dirigeable would be able to achieve escape velocity. No reeeaaalllllllyyyyy? I wonder how this rhymes with:

Originally posted by Wikipedia
The third stage is an "orbital airship" (Orbital Ascender), which takes payloads to low earth orbit via an ion engine in three to nine days (i.e., it accelerates itself horizontally to orbital velocity and gains sufficient altitude). Their estimated marginal costs are one dollar per ton per mile of altitude, and their development costs thus far have been under one million dollars.

you missed the point I was trying ot make. There is no way we can make a lighter then air craft achive orbit by itself via its bouyancy in air.

What you quote was exaclty what I was explaining... where are you going ot get the energy needed to use the ion engine? how much cargo are you going to carry into orbit? The more weight you add the less feasible it is to use a lighter then air body. You canot jsut strap on an ion engine to the good year blimp and expect it to be able to achive orbit

Well duh. Trying to explain it would never work was the point of my original post. Your reaction to my post was that it is not claimed to be the goal to use airships to achieve orbit in the first place, which was wrong.