Air Ship To Space?

A while ago I saw an idea for an "Airship To Space" on JP Aerospace's website.
How does this work? They mentioned using electric rockets which have very low
thrust.

In article ,
ChrisV01 wrote:
A while ago I saw an idea for an "Airship To Space" on JP Aerospace's website.
How does this work? They mentioned using electric rockets which have very low
thrust.

Nobody outside JPA has been able to figure out how it could possibly work;
the numbers do not add up. (Or rather, they add up to "absolutely no way".)
Either they have some *very* subtle trick in mind, or they've goofed badly,
and currently the betting is on the latter.

It doesn't help that very little technical detail on their scheme is
available.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

How does this work? They mentioned using electric rockets which have very
low thrust.

You asked how ATO, Airship To Orbit, would work and all they said was that
since they don't know how it would work, it probably wouldn't.
Ah, the conceit of pessimism. It, not the shallow gravity well, is what keeps
us stuck on the ground.
How it works: The launcher station floats very high where the air is 1% as
thick as at the ground. An V-shaped orbiter airship a mile long is assembled on
station. This orbiter uses its own positive buoyancy to float upward to 40
milles high where the air is even less dense and which is halfway to a lower
LEO.
Then electric ion propulsion is used to accelerate the giant airship forward
and up. [JPA is looking at standard Hall thrusters as well as proprietary ion
thrusters.]
The orbiter's angle of attack is upward so the thin air compresses under the
Vee-shaped ship and raises its altitude. The higher it goes, the thinner the
air and the less the drag and the faster it goes. Repeat until orbit is
reached.
This is not rocket science, it is high altitude aerodynamics.

^
//^\\
~~~ near space elevator ~~~~
~~~members.aol.com/beanstalkr/~~~

(ChrisV01) wrote in message ...
A while ago I saw an idea for an "Airship To Space" on JP Aerospace's website.
How does this work? They mentioned using electric rockets which have very low
thrust.

I know that the space station feels around 3 lbs of drag in its normal
orbital range between 150 and 250 miles altitude where the atmospheric
density is about 3 to 6 billionths of STP at MSL. I also know that
many people are proposing electrodynamic tethers to reboost
spacestations powered by mutiple 10 kilowatt lasers from the ground.
So why couldn't JP aerospace be using some form of electrodynamic
tethers powered by lasers on the ground to dynamically lift themselves
higher to get into space from whatever altitude they can muster from
bouyancy alone? I would love it if someone like Henry Spencer could
run the numbers and show his work on this idea.

In article ,
Allen Meece wrote:
The orbiter's angle of attack is upward so the thin air compresses under the
Vee-shaped ship and raises its altitude. The higher it goes, the thinner the
air and the less the drag and the faster it goes. Repeat until orbit is
reached.
This is not rocket science, it is high altitude aerodynamics.

Yes, and we know how high-altitude aerodynamics works, and it's not good
enough. When you start looking at numbers, not just handwaving about "the
less the drag", they appear to need a positively miraculous L/D ratio to
make this thing work as described, and there's no hint of how they could
possibly do that.

It remains possible that they have some clever trick in mind. But "you
just kinda float up and then start accelerating slowly" is nowhere near
clever enough.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

(Allen Meece) wrote in message ...
The orbiter's angle of attack is upward so the thin air compresses under the
Vee-shaped ship and raises its altitude. The higher it goes, the thinner the
air and the less the drag and the faster it goes. Repeat until orbit is
reached.
This is not rocket science, it is high altitude aerodynamics.

So thin enough that the kinetic energy of the gas striking the ship,
which would be traveling upwards of several kilometers per second,
doesn't exceed the melting point of the very fragile hull? Just
curious.

--
Bob

(Allen Meece) :

How does this work? They mentioned using electric rockets which have
very
low thrust.

You asked how ATO, Airship To Orbit, would work and all they said was that
since they don't know how it would work, it probably wouldn't.
Ah, the conceit of pessimism. It, not the shallow gravity well, is what
keeps
us stuck on the ground.
How it works: The launcher station floats very high where the air is 1%
as
thick as at the ground. An V-shaped orbiter airship a mile long is
assembled on
station. This orbiter uses its own positive buoyancy to float upward to 40
milles high where the air is even less dense and which is halfway to a
lower
LEO.
Then electric ion propulsion is used to accelerate the giant airship
forward
and up. [JPA is looking at standard Hall thrusters as well as proprietary
ion
thrusters.]
The orbiter's angle of attack is upward so the thin air compresses under
the
Vee-shaped ship and raises its altitude. The higher it goes, the thinner
the
air and the less the drag and the faster it goes. Repeat until orbit is
reached.
This is not rocket science, it is high altitude aerodynamics.

Yes, and with high altitude aerodynamics you get drag that you have to
overcome. The cost of the drag is why no-one see why it will work.

Earl Colby Pottinger

--
I make public email sent to me! Hydrogen Peroxide Rockets, OpenBeos,
SerialTransfer 3.0, RAMDISK, BoatBuilding, DIY TabletPC. What happened to
the time? http://webhome.idirect.com/~earlcp

(Tony Rusi) :

(ChrisV01) wrote in message
...
A while ago I saw an idea for an "Airship To Space" on JP Aerospace's
website.
How does this work? They mentioned using electric rockets which have
very low
thrust.

I know that the space station feels around 3 lbs of drag in its normal
orbital range between 150 and 250 miles altitude where the atmospheric
density is about 3 to 6 billionths of STP at MSL. I also know that
many people are proposing electrodynamic tethers to reboost
spacestations powered by mutiple 10 kilowatt lasers from the ground.
So why couldn't JP aerospace be using some form of electrodynamic
tethers powered by lasers on the ground to dynamically lift themselves
higher to get into space from whatever altitude they can muster from
bouyancy alone? I would love it if someone like Henry Spencer could
run the numbers and show his work on this idea.

Because until it is at near orbital speeds already the tether can not be
deployed. The end of the tether must be already moving above orbital speeds
to pull up the rest of the tether. Tethers are useful to maintain or boost
objects in orbit already.

--
I make public email sent to me! Hydrogen Peroxide Rockets, OpenBeos,
SerialTransfer 3.0, RAMDISK, BoatBuilding, DIY TabletPC. What happened to
the time? http://webhome.idirect.com/~earlcp

So thin enough that the kinetic energy of the gas striking the ship,
which would be traveling upwards of several kilometers per second,
doesn't exceed the melting point of the very fragile hull? Just
curious.
It's well known that it is the compression of the incident air that heats
it. This puffball of a spacecraft won't compress the air enough for high
temperatures like a metal ship would.
^
//^\\
~~~ near space elevator ~~~~
~~~members.aol.com/beanstalkr/~~~

they [JPA] appear to need a positively miraculous L/D ratio to
make this thing work as described, and there's no hint of how they could
possibly do that.

Correct about the no hint. They just say the "ion engine for the orbiter will
be tested in the next five months." There are a few different types of ion
engines. There is a concept that ionizes the slipstream and magnetically
propels it rearward so the airship "swims" through the air.
Heard of that one?
I think it might be the "proprietary ion engine" which Skystation
initially intended to use but had to abandon and go to solar electric
propellers. ?
In other words, there is more than one way to skin an orbit. Let's get
behind JPA and wish them success. So what if they can't or won't right now tell
us how to make an ATO, Airship To Orbit. It will be an affordable and wonderful
thing to slowly accelerate to orbit. Space will become closer to all of us when
this concept flies.
^
//^\\
~~~ near space elevator ~~~~
~~~members.aol.com/beanstalkr/~~~