Comments on: A curmudgeonly opinion on commercial human spaceflight

By: Nemo

Nemo — Sat, 05 Nov 2005 02:00:11 +0000

Telemetry reporting what? The experience of riding up and down in the SS1 crew compartment?

Well, duh. That “experience” is called micro-G, and SS1 could have provided it more cheaply than any sounding rocket.

By: David Davenport

David Davenport — Fri, 04 Nov 2005 23:46:06 +0000

The win is that you can dispense with the need for telemetry, since you recover the payload after landing.

Telemetry reporting what? The experience of riding up and down in the SS1 crew compartment?

By: Nemo

Nemo — Fri, 04 Nov 2005 02:05:35 +0000

Uh, how to eject the payloads from the cabin? Just open the hatch?

Who said anything about ejecting the payload? It’s a suborbital rocket – the payload would ride up and down with SS1. The win is that you can dispense with the need for telemetry, since you recover the payload after landing.

You very obviously know nothing about Rutan and SS1. He has said more than once publicly that SS1 “has a known design flaw,” the flaw being insufficient wing dihedral.

Yes, I’m aware of that. He has also made multiple claims about how safe SS1 is, which contradicts his admission about the dihedral.

By: David Davenport

David Davenport — Fri, 04 Nov 2005 00:46:41 +0000

… You’d think, if SS1 was as safe and reliable as Rutan’s (and others’) rhetoric, then he would have kept flying it after winning the X-Prize. It would have been a valuable testbed for SS2, and he could have turned a profit by piggybacking some sounding rocket payloads in the other two seats.

Uh, how to eject the payloads from the cabin? Just open the hatch?

It is quite understandable that he wouldn’t want to risk an accident prior to handing the vehicle to the Smithsonian, but if the vehicle was really as reliable as claimed, that risk would have been negligible. So his actions indicate that his private assessment of SS1 reliability was more realistic than his public rhetoric.

You very obviously know nothing about Rutan and SS1. He has said more than once publicly that SS1 “has a known design flaw,” the flaw being insufficient wing dihedral. This lack of dihedral causes SS1 to be unstable about the roll axis during ascent after release from the mothersip.

No, it’s not cost effective to build a new wing for SS1.

By: Nemo

Nemo — Tue, 01 Nov 2005 21:02:12 +0000

As I understand it, Soyuz flights are six months apart because that’s the on-orbit shelf life of a Soyuz.

Correct. Actually, the cert limit is 200 days. They fly six months apart so they have a little margin in case of delays.

This is why you have two flights per year even with tourists; it’s all the ISS budget will subsidize.

Exactly my point. If the tourist flights were truly profitable, they wouldn’t need the subsidy and therefore could fly more often.

By: Roger Strong

Roger Strong — Tue, 01 Nov 2005 19:04:32 +0000

As I understand it, Soyuz flights are six months apart because that’s the on-orbit shelf life of a Soyuz.

Even if you weren’t rotating crew, you’d still need to keep replacing the Soyuz. They did that – A visiting crew would launch in a brand new Soyus, move their custom-molded seat cushions to the Soyus that had already been in orbit for six months, and return in that one a few days later.

Pre-Columbia-loss, this was to make sending tourists to ISS affordable – when you’re swapping a Soyus for a new one, the trip is already paid for out of the ISS budget. A paying cargo (the tourist) is gravy.

Post-Columbia-loss, the tourist takes the third seat with the new ISS crew, and returns on the six-month-old Soyus with the old crew. Again, the Soyuz is paid for by the ISS budget. You’re not filling the third seat with supplies, so you lose some money sending them on the next Progress flight.

This is why you have two flights per year even with tourists; it’s all the ISS budget will subsidize.

By: Nemo

Nemo — Tue, 01 Nov 2005 18:49:28 +0000

I believe they are also constrained by the Space Station’s ability to accept them.

Why? The station has demonstrated the ability to accept six shuttle flights and two Soyuz flights in a single year, so I don’t see how (say) four shuttle flights and four Soyuz flights would be a problem. What “constraint” do you have in mind?

I know there was talk at some point of flying independent Soyuz missions, but presumably customers wanted to go to the Space Station, not spend their whole trip stuffed into a can.

Especially because Soyuz is limited to four days of independent flight.

NASA won’t let them send more than two flights a year — as you may recall, it was a fight to get that much.

Not only do I not recall it, I am highly skeptical of it. Two Soyuz per year has always been a floor, not a ceiling. It’s been driven by the Soyuz operational certification limit of 200 days. In fact, it has been the Russians that have pushed for longer expedition stays – NASA’s standard ISS crew rotation with the shuttle pre-accident was 135 days, while now it’s 180 days.

By: Donald F. Robertson

Donald F. Robertson — Tue, 01 Nov 2005 18:14:02 +0000

Bill: $100 million is a single Space Adventures “Apollo 8″ using Soyuz and a Proton Block DM. One tourist.

I don’t have time to confirm this right now, but I thought the plan was to fly two tourists and a pilot on each mission. If so, the “income” from the mission would be $200 million, and the cost presumably somewhat less than that.

Nemo: If they were really turning a clear profit on Soyuz tourists to ISS, they would have ramped up production to fly more than two per year.

While this may be true, I believe they are also constrained by the Space Station’s ability to accept them. I know there was talk at some point of flying independent Soyuz missions, but presumably customers wanted to go to the Space Station, not spend their whole trip stuffed into a can. If the market is for Space Station flights, NASA won’t let them send more than two flights a year — as you may recall, it was a fight to get that much. So, I’m not sure how much, if anything, the flight rate says about the profitability or otherwise of this program.

– Donald

By: Nemo

Nemo — Tue, 01 Nov 2005 17:11:57 +0000

Nemo: want to place an over/under bet on $5 million to orbit for a 100 kg person in 2015?

Nope, but I’d take the “under” on $10 million or the “over” on $1 million. The size of the market is too uncertain to slice it any finer than an order of magnitude.

$100 million is a single Space Adventures “Apollo 8″ using Soyuz and a Proton Block DM.

You misspelled “Zond”. Space Adventures’ mission would not enter lunar orbit, therefore it doesn’t qualify as “Apollo 8.”

$5 million per person to orbit? Soyuz costs that now. Some say Dennis Tito’s $12 million “whisper number” was enough to pay for the entire launch of 3 humans to LEO.

Some disagree. One piece of counterevidence is that the USSR once had the capability to launch six Soyuz spacecraft per year but now flies only two. If they were really turning a clear profit on Soyuz tourists to ISS, they would have ramped up production to fly more than two per year. It’s been four-and-a-half years since Tito’s flight, so they’ve had more than enough time. That tells me that one of the following must be true:

1) The price of a tourist seat on Soyuz is not enough to pay the fully-loaded cost of the flight, or,

2) The price is enough but the size of the Soyuz tourist market is too small to justify ramping up Soyuz production (and many alt.spacers have claimed to me that this cost is trivial).

Another piece of counterevidence is that Russia plans to charge NASA $65 million per Soyuz flight once the current agreement expires, if the INA is amended.

And finally, there are insider statements like this:

“Anderson also pointed out that seats on the orbital flights to the ISS were part of missions already bought and paid for by the Russian government.”

By: Bill White

Bill White — Tue, 01 Nov 2005 16:05:34 +0000

$100 million is a single Space Adventures “Apollo 8″ using Soyuz and a Proton Block DM. One tourist.

$5 million per person to orbit? Soyuz costs that now. Some say Dennis Tito’s $12 million “whisper number” was enough to pay for the entire launch of 3 humans to LEO. 2 were government crew and the 3rd a tourist.

$4 million per person, a few years ago.