NASA to consider extending Shuttle life

[Fat Tone]

http://news.bbc.co.uk/1/hi/sci/tech/7590449.stm

Sadly a little light on detail but it does raise some interesting points.

[Dr Mordrid]

But the main point is that many of the systems and employees that would be necessary to extend the program either no longer exist or soon will not exist. One of these is the ability to build the shuttles external tanks - they're preparing to dismantle and recycle (destroy) its tooling and gear at Michoud, Louisiana literally in the next few weeks so they can build systems for the Constellation (Orion, Ares I & Ares V) program. It's a situation where NASA can only build one or the other, not both.

[Evildead666]

Hmmm, what about the ATV then ?
It doesn't leave much...either Soyuz, or ATV or keep the Shuttle going, pushing the Constellation even further back....

I would probably place my bets on the ATV...its worked so far

[Dr Mordrid]

Soyuz is out for safety and political reasons - the latter requiring an exemption from Congress to the Iran embargo which Russia is violating. Not bloody likely in todays environment.

ATV isn't planned to be built in large enough numbers and it's so far not man-rated. Also might be more costly than Dragon or whatever Lockheed-Martin is working on for Bigelow - either their own 8 man PTV or the Dream Chaser.

[Fluff]

The space shuttle looks cooler than the orion.

Do you think there will be another plane type space aircraft again?

[Dr Mordrid]

A spaceplane is of limited usefulness with its only advantage being that of landing on a runway. It's also useless for any mission beyond LEO - low earth orbit. Wings etc. are totally useless for a moon, Mars or deep space mission. Also; the airframe and airfoils cause the booster to loft weight that could in most cases be better used to loft cargo.

Look at the shuttle: the orbiter weighs over 100 metric tons and can only carry 29 metric tons of cargo. Use the same booster hardware and one could loft 129 tons of cargo then loft th4 crew on a smaller Atlas V sized booster.

Another problem is that it takes a lot of maneuvering to burn off all the energy of 100 metric tons coming in at 17,000 mph - the orbiter has to execute several slow S turns to do so. Coming in straight would turn it into what happened to Columbia even with an intact heat shield.

On the other hand a capsule coming in from LEO, the moon or a planetary mission can come in almost straight in - though modern capsules do have some 'flight' capability so as to adjust their terminal trajectory. Hell; a capsule can come in at 25,000 to 30,000 mph.

There are two spaceplanes that are under active development:

1. the SpaceDev Dream Chaser lifting body


which is based on the NASA HL-20



which itself is based on a re-engineering of the Russian BOR-4



Good for LEO, within the payload loss due to lofting an airframe and wings, but as noted not for lunar, Mars or deep space missions. A heat shield for it and the structural changes would make it too heavy for deep space re-entries.

The most interesting part of its story is that it went black as soon as Bigelow (of the private space stations) and Lockheed Martin signed a deal to launch Bigelow's modules and crews for their private space stations. Before this SpaceDev also signed a deal with Lockheed Martin to man-rate the Atlas V for launching the Dream Chaser. You add it up.

2. the Russian Kliper, which they continue to interest the Europeans in co-funding (no luck yet). Kliper is a sturdy lifting body design that is half capsule/half 'spaceplane' that may well handle lunar/deep space re-entries because of a better heat shield. Status: in flux.