ISV Venture Star

[MarkD]

There are more than two people given the interior of the cryo vault. There are doctors and other people to keep an eye on the passengers there. My guess is up to 20 or 30 people as ISV crew only.

[exostrike]

There are more than two people given the interior of the cryo vault. There are doctors and other people to keep an eye on the passengers there. My guess is up to 20 or 30 people as ISV crew only.

According to the wiki there is a four man flight crew, rotating between two man team while the other goes into cryosleep. Its possible that when it comes to revive the passengers they wake up medical staff (who have trained in cryosleep methods) first to assist in reviving the rest. Either that or Jake's batch wasn't the first ones to be woken up.

Though when I think about it two people operating in an inclosed space with no direct outside stimulation apart from out of date recordings seems like a recipe for psychological melt down

[MarkD]

Well it is proven on the Mir Space Station what happens with little human contact you will go crazy.

They don't have out of date anything given the faster than light communications system to talk to Earth during the six year voyage.

I could see a photo like this of the ISV taken by one of the Valkyrie shuttles of it's sister ship still docked to the ISV. http://rocketry.files.wordpress.com/...6/endevour.jpg This photo is of STS-134, Endeavour's last mission.

[exostrike]

They don't have out of date anything given the faster than light communications system to talk to Earth during the six year voyage.

The faster than light communications can only really deliver short text messages since they are limited to 8 bits per hour. This probadly means any direct messages to earth would only be progress reports or reports of cryofailure. Given thier simplistic nature they give no genuine human contact, this could actually create an interesting situation where a mad crew member tries to workout if the messages he is getting are from real people or automatic reponses from a computer

[MarkD]

The movie Moon pokes at this, where it's one guy left alone on the moon and his only companion is a robot. It's a good movie too, similar to Avatar's themes of corporate greed and all.

[exostrike]

There is one point that people may not know, the Venture star is actually a complete rip off of the Valkyrie Antimatter Starship by Charles Pellegrino and Jim Powell, see here for more info about that ship: Slower Than Light - Atomic Rockets

However there is a reason for this, Dr. Pellegrino was a scientific consultant on the film and a friend of Cameron already. how? Pellegrino is a world expert on the Titanic and so was hired for Cameron's Titanic movie.

[RD-701]

The ISV isn't a complete ripoff; the only real similarity I can see between it and the Valkyrie concept is having the engines preceding the rest of the ship ("puller" arrangement). The differences are far more numerous:

1. The main structural element of the Valkyrie connecting the payload and propulsion sections is a tether. The payload traverses along this tether. The ISV connects the propulsion segment to the payload with a truss.

2. The Valkyrie has two drive sections; one for acceleration, the other for deceleration. Instead of flipping around, it simply uses the opposing drive section for deceleration. The ISV has only one drive section, but uses either its engines or lightsail depending on the phase of the mission (and flips around mid-flight for the deceleration phase). The Valkyrie has no lightsail.

3. The Valkyrie's engine is an antimatter beam-core, i.e. colliding particle beams of protons and antiprotons is the basic mechanism of the engine. I have no clue what the ISV's engine is, it sounds like no other antimatter engine I have ever heard about- some sort of hybrid between a plasma core antimatter engine and a photon drive. I have no clue as to how such an engine would work.

4. The Valkyrie uses a liquid droplet radiator to shed waste heat from the engine. Droplets of hot liquid are sprayed out of the front of the spacecraft, cool, and fall back onto the ship as it accelerates. This droplet radiator is also the debris shield used by the vehicle during acceleration. The ISV uses more conventional radiators, though for some reason they seem to be optimised for convective rather than radiative heat transfer.

5. During acceleration the Valkyrie uses the droplet radiator as a shield from space debris (at such high velocities, small dust particles can cause huge damage). During deceleration, the other engine uses its droplet radiator as a radiator, but it cannot be used as a debris shield. Instead a series of umbrella like dust shields, made of Mylar or a similar substance, are dangled on the end of the tether. The ISV has less defence- while it has vaguely similar dust shields (that also act to shield the crew section from the lightsail laser), they are fewer in number than those used by the Valkyrie, and the vehicle has no considerable defence during the acceleration phase (either under laser or internal propulsion).

It should be noted however that the Valkyrie is travelling faster than the ISV, so the ISV would logically require less protection (the kinetic energy of incoming debris would be lower).

I probably just described all of that in horribly complicated science-speak... sorry.

Also, I have some potential criticisms about the ISV's scientific validity, but they issue is probably too complicated to explain in this post.

[exostrike]

oh don't worry I understood it (mainly), yeah when you break it down the ISV is not really a rip off, its just not 'orginal' as some might expect.

Yeah, when you start breaking down the numbers the ISV doesn't really work. But I think Cameron would consider anyone who broke down those numbers to have too much time on his hands.

Heres a thread on another forum about the flaws in the craft: Financial aspects of spaceflight - Orbiter-Forum

[exostrike]

I've discovered that ISV's remain in system for 1 year before returning to earth just in time for the next one to arrive, suggesting that they had a rudimentary evacuation plan incase the Na'vi did overrun them. Thought 2154 it seems obsolete due to the number of people at Hell's Gate.

[RD-701]

I don't think the loiter period is necessary for evacuation, just for the whole ISV schedule and the logistics involved. It probably takes a year-long period to unload hardware from the ISV and load unobtanium and other cargo back onto it. Not to mention the time it must take to gather the deuterium/hydrogen for the trip back to Earth, and perform the checks/maintenance that the ISV probably needs before being shot back up to 0.7 c.