Grant Bonin discusses the papers put out by the Space Frontier Foundation and the GAO on problems with NASA's exploration plans in todays issue of The Space Review.

It's worth the read, but being busy working on same plans, I would comment only on this bit:

Human-rating either the Atlas 5 or Delta 4 is likely to be an expensive proposition regardless of the fact that both boosters have already been developed (especially since no one really knows what it means to “human rate” these machines, beyond ensuring they don’t kill anybody). Also, since both the Atlas and Delta lines have very different assembly and integration processes (Boeing, for example, assembles its rockets horizontally for ease of access, while Lockheed uses a vertical integration facility), it may be particularly difficult to human-rate both varieties of launchers, and one option may inevitably gain preference as a result.

I agree that no one knows what human rating means, other than an excuse for NASA to not use the vehicle (since there hasn't been a human-rated spacecraft built, at least by the US, since the sixties). All I think that it should mean is to put in some kind of Failure Onset Detection (FOSD) that gives the astronauts enough warning that things are heading south to punch out. I don't understand why Grant thinks that assembly orientation would have anything at all to do with it.

There is a lot of internal debate about the relative merits of an EELV based solution versus various versions of the CLV from Thiokol/Horowitz. The internal folks at NASA have dismissed the Delta IV from consideration due to its steep launch trajectory. This would impose unacceptable loads on the human portion of the payloads. The Atlas V would do just fine.

If one is really interested in figuring out what it takes to human rate a launch vehicle one can download from the NASA NTRS server, the Saturn 1B/Command Service Modular technical specifications that were used for the Apollo/Soyuz flight. This document has extensive information on the criterion used for the man rating of the Saturn 1B/CSM stack.

Hint: The Atlas V booster reliability is stated at 0.98 by Lockmart and the Saturn 1B booster reliability is stated at 0.84 with a 0.99 overall crew surviability rating. (Note: this was after 20 something flights. NASA was more honest back then).

The only reason that it is not being considered is that Horowitz/Griffin don't want to and threaten to punish Lockmart every time the subject is raised.

I thought man-rating a launch vehicle had to do with loads on the crew. Can the vehicle get into orbit without placing too high of a loading on the people inside, who are more delicate than a satellite would be? You would have to change the flight profile of the Delta/Atlas, and then determine if you took away too much performance.

But it's not impossible to do, is it? We've done it before.

Oh no, we have to go develop an entirely new vehicle. With "Shuttle derived parts".

I thought man-rating a launch vehicle had to do with loads on the crew.

That's only one factor. There's nothing about a nominal launch on Delta that causes problems from an acceleration standpoint. The issue relates to aborts.

Astrosmith,
I've always heard three 9s survivability of the crew. 99.9% chance of survival. Many things go into the equation that produces that number. Unfortunately, many more things go overlooked, and some things are given greater weight than they should.

So then what is it about Delta or Atlas that makes Griffin not want to use it for CEV/Ares?

So then what is it about Delta or Atlas that makes Griffin not want to use it for CEV/Ares?

EELVs cannot be strapped to the Ares V.

Using 5 segment SRBs (Ares 1) helps assure the Ares V (which uses 2 segment SRBs) actually gets built.

Ares V uses 2 5-segment SRBs. ;-)

Actually Atlas V core stages can be strapped to an Aries V. This was proposed several years ago as the liquid flyback option for the Shuttle.

The only reason that the Aries 1 is a solid is because Horowitz's came from Thiokol. Here is that part of his bio.

NASA EXPERIENCE: Selected as a pilot by NASA in March 1992, Scott reported to the Johnson Space Center in August 1992. He successfully completed a year of initial training and assignments since then include: working technical issues for the Astronaut Office Operations Development Branch; support crew at the Kennedy Space Center for Shuttle launches and landings; and spacecraft communicator (CAPCOM). A veteran of four space flights, Scott has logged over 1,138 hours in space. He served as pilot on STS-75 (1996), STS 82 (1997) and STS-101 (2000), and was crew commander on STS-105 (2001). Scott Horowitz retired from NASA in October 2004 to serve as Director of Space Transportation and Exploration at A.T.K.-Thiokol in Utah. In September 2005 he returned to NASA as Associate Administrator for the Exploration Systems Mission Directorate, NASA Headquarters, Washington, D.C.

So Bill, are you saying that the reason that NASA doesn't use the Atlas or Delta is that they are determined to do it themselves?

I figure that the prime motivator is keeping 20 thousand people employed at NASA, rather than efficiency or economy.

> EELVs cannot be strapped to the Ares V.

Why do you think that? Delta IV common core modules were specifically designed to be strapped together.

>> Saturn 1B booster reliability is stated at 0.84 with a 0.99 overall
>> crew surviability rating. (Note: this was after 20 something flights.
>> NASA was more honest back then).

> I've always heard three 9s survivability of the crew. 99.9% chance of survival.

0.99 overall implies the escape system would fail 6.25% of the time (one in every 16 ejections would be unsuccesful). Given the history of escape capsules, that seems quite reasonable (perhaps even optimistic).

On the EELV versus Ares 1 & Ares V issue is it a

90 / 10 bad decision? or

75 / 25 bad decision or

51 / 49 bad decision?

In dollars, how much would NASA save (from various perspectives) by using Atlas V rather than the 5 segment SRB?

= = =

If Atlas V is okay for NASA to use even with those Russian engines, why not merely license the R-7 and Soyuz technology and save even more money?

Another question - - if Elon Musk truly does accomplish an order of magnitude reduction in launch costs won't EELV and Ares both become obsolete at the same time?

If that is true, why does it matter which is selected by NASA today?

How does "using 5 segment SRBs (Ares 1) helps assure the Ares V (which uses 2 segment SRBs) actually gets built."? I'm not convinced.

If budget push comes to shove in 2010 or so, does the argument "look, we have this Ares V subsystem finished!" really make a difference?

NASA had multiple Saturn Vs ready for Apollo Applications missions but they still got cancelled.

If that is true, why does it matter which is selected by NASA today?

It matters because if CLV goes over budget, it will quickly eat up funding from the COTS program. That would leave no funding for entrepreneurs like Elon to develop the manned spacecraft that will make EELVs and CLVs obsolete. The budget pressure is caused by the combination of schedule and program complexity. The schedule is driven by the Shuttle retirement date. Building a new booster instead of reusing the EELVs increases both complexity and risk. Unless something gives, this will cause a major budget crunch at NASA in a few years, and the first projects to be cancelled will be the ones NASA sees as duplicated effort and the ones without an army of NASA employees and contractors to feed.

> Another question - - if Elon Musk truly does accomplish an order of
> magnitude reduction in launch costs won't EELV and Ares both become
> obsolete at the same time?

If "obsolete" means they will be retired, that depends on several factors.

If the goal is to protect the Shuttle workforce, then it doesn't matter how many cheaper rockets are developed -- anything you replace the Shuttle with will have to employ just as many people, which means it will be just as expensive.

> If that is true, why does it matter which is selected by NASA today?

Is that a trick question? I matters because one of them requires more money than the other one, and most of us have to pay Federal taxes for such things.

How does "using 5-segment SRBs (Ares 1) helps assure the Ares V (which uses 2 5-segment SRBs) actually gets built."? I'm not convinced.

It doesn't assure Ares V gets built, however look at the reverse case. If EELV is used for CEV and Ares V doesn't fly until 2017 or 2018 and orbiter is retired in 2010 Thiokol has no customers for its SRBs for seven or eight years. Employees get laid off, etc . . .

Ares 1 does not assure Ares V however an EELV CEV makes actually building Ares V far less likely.

We can disagree whether that is a feature or a bug however the question was why did Mike Griffin
choose the Ares 1 design. In my opinion to better protect his intention to fly Ares V and to amortize 5 segment SRB development costs over two boosters, the Ares 1 and the Ares V.

Bill, why exactly do we need Ares V again? That part hasn't been made clear.

Mars Chris, Mars.

Assuming the given EELV to mars approach where only one in twelve launches actually carries people, why would the Atlas or Delta launch vehicles need to be human rated anyway?