Separate Cargo and Personnel Missions for NASA?

l8f57 writes "Hal Gerham (from the NASA CAIB report) is calling for cargo and people to be separated into different missions. He also goes on about how a re-usable spacecraft may not be the most cost efficient vehicle."

Comments

Maybe, but....

[ChrisHanel]

Ironically, the astronaut's luggage would accidentaly be rerouted to Topeka.

Re:Is This Wise?

[stratjakt]

I believe this is about minimizing cost and lead times, not risk reduction.

I think the idea is that each type of ship would have different requirements, so you could design each to meet the requirements of its cargo, be it human or stuff.

Ie; a cargo shuttle full of tiny screws to be sorted in space doesnt need fancy atmospheric systems and oxygen recirculators and a seven million dollar toilet, etc.

The Russians did this, all through Mir. They had the Soyuz (sp?) rockets for people, and another kind to send supplies up. Or something like that.

Sure makes sense for large missions

[scottganyo]

For example, if you were planning to start a colony on Mars, you could use cheaper methods to send the suppies to the planet ahead of time. Then, use the most reliable methods to send the people. The whole enterprise would be cheaper, you could use the most reliable methods to ensure that the colonists would arrive safely, and you could guarantee that the supplies would be waiting for the colonists when they did arrive.

Re:Is This Wise?

[gantzm]

Sorry, you are wrong. So if I purchase a lottery ticket tonight and win, are my odds now 1 in 1 of winning the lottery if I purchase another ticket? Past performance does not dictate future performance a string of close spaced events will most likely be outweighed put future events being spaced further apart.

Re:Easier to have single-use ships?

[ChrisHanel]

...thank goodness we're not in the Federation yet, or we might have to worry about that.

Seriously, our ability to send any kind of material close to effecting another civilization of any kind is nil. We can't even get next door without hyperventilating, let alone outside the solar system to throw garbage on Spock's lawn.

Let's just have this conversation again in 100 years, k?

ENTER the space elevator

[Chuck Bucket]

This makes sense, and I'd love to see something like the space elevator that Arthur C. Clarke's brought up in Fountains of Paradise happen. This way, cargo could be brought up, followed by crew if the cargo run was successful.

An article written about the idea, this year:

Space Elevators Maybe Closer To Reality Than Imagined

Much more info here:

The Space Elevator Reference

CB

This is a good thing

[Dav3K]

I agree with this. By separating out the cargo, the personel-carrying missions can actually become more predictable (less variance due to cargo weights) and are unencumbered with the reusability goals. This means Safety can always be the primary goal for person-carrying missions.

Cargo missions are a much more appropriate area to experiment with reusability or cost-lowering goals as the failure costs are significantly lower. NASA would have a much easier time explaining how they blew up a $40 billion cargo payload to the press compared to the media frenzy created when an astronaut dies.

Just look at the media attention given to this last disaster - how much was covering the loss of human life and how much was covering the financial losses incurred?

Re:Is This Wise?

[RevMike]

Name one thing that they would need to bring up as cargo, that NASA could not replace....?

If they sent up DVDs so the astronauts could watch movies, they could not replace them since the MPAA wouldn't let them rip a backup copy before the mission left.

Re-usable is only the cheapest when...

[cmowire]

You are using it all the time.

We really haven't explored the limits of reusability or expendability.

If we were to contract out for expendable boosters, built in as cheaply and expendably as possible in batches of 100, it would end up with the launch costs way below what they are now. Our current batch of expendable boosters are far too complicated and are built far too slowly to give us savings like this. This is what is called the "Big Dumb Booster" notion.

The shuttle is a poor example of reusable boosters. The cost for refurbishing between launches, maintaining an army of technicians, etc. is incredible. If we were able to fly one, with the same safety and without appreciable yearly budget increase, once every week, the shuttle would start to look good.

The CAIB's trying to say what has been repeated over and over and over again. One of the reasons why the shuttle has problems is because they tried to create one space vehicle that can do everything. It's like trying to combine a sedan, truck, and crane into one vehicle.

And it's probably easier to build an inexpensive production-grade partially or fully reusable craft before somebody gets a better idea if it just has to do one or the other.