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Falcon launch vehicle items
Falcon launch vehicle components sitting in the SpaceX factory in El Segundo, California. (credit: Ken Gosier, Space Frontier Foundation)

Interview: a tour of SpaceX (part 2)

Interstage

Sam Dinkin, The Space Review: So you use cheap disposable components, but expensive reusable components?

Dianne Molina, Marketing Manager, SpaceX: The first stage is aluminum 2219. That will be recovered. It’s somewhat of an experiment at this point. We make no bones about saying how we’re going to get that first stage back. What shape it’s going to be in. How we can refurbish? How we can extend that cost savings in terms of reuse.

TSR: One of the many things we want to find out after you launch.

Molina: Absolutely. Absolutely. As do we. As do our structures folks.

Ken Gosier, Space Frontier Foundation (and amateur photographer): Can we touch [the second stage faring]?

Molina: If it’s going to withstand exiting the atmosphere, you can touch it.

We went from having an aluminum interstage to—we are pretty early in the process—a composite design. Composite is the honeycomb material that you see in kind of a circle. The interstage is over there, the skirt over here. You can touch that too. Not the one that’s covered.

Bill Boland, Space Frontier Foundation and Winner of VIP Tour: You manufacture that here?

Molina: What I can tell you about that process is—the big joke is, “We’re always trying to lose weight.”

So we have a phenomenal director of structural dynamics who actually came to us with a background. He worked at SPACEHAB, and he worked at several other places, one of them being Indy Car. He came with knowing micro carbon fiber materials, understanding something from other industries. That’s a big thing that Elon’s into: learning from industries that are doing well, and not being so stuck in one way of doing things. Learning from other industries, what they do well, and what we can capitalize on: not reinventing the wheel, basically. He came to him with this proposal of the composite interstage.

“That’s a big thing that Elon’s into: learning from industries that are doing well, and not being so stuck in one way of doing things.”

Elon said, “Do all the analysis you need to prove it out to me and to yourself that it will work.” They looked at it, had the design in place, bought the materials they needed, and had a perfect first iteration of it. No flaws, no structural issues, strength issues, bonding issues, nothing. It was a matter of probably six to eight weeks. Again, if you didn’t have Elon giving you the go ahead, this process would have taken months and months and months, probably years, to get that kind of new component being decided on, designed, tested and into fruition.

TSR: Nice to have a rocket man in charge.

Molina: It’s a dual situation. When I purchase for my programs, my marketing materials for conventions, it comes from someone’s pocket, not some kind of faceless entity. That creates huge accountability.

TSR: You get to see him every Friday at lunch and look him in the eye.

Molina: Absolutely.

Rick Tumlinson, Spokesman, Space Frontier Foundation: Do you come from an aerospace background?

Molina: I don’t. I come from a journalism and communications background. I worked for a firm called Ketchum with Mattel, a large multinational firm, as a client. I also worked at Caltech and UCLA in communications. I learned a lot from working at Caltech about communicating highly technical information, disseminating that, making it palatable.

TSR: So we look like we already know what “interstage” means.

Molina: Unfortunately we don’t have a fully integrated vehicle right now because that would really visually make more sense. I recommend going on the web site (http://www.spacex.com/falcon_i.php) and then it really starts coming together regarding how the vehicle will stack out.

The interstage will be exactly that. It will be the stage between the first stage and the second stage. In that is a parachute that will actually bring most of the first stage back. Then you have Kestrel engine, a pressure-fed system that fits into the interstage and the second stage, and then the nose cone, where the payload will sit along with the avionics: the guidance control, the computer, the brain of the vehicle. That’s it. Simple.

Gigantic oven

Molina: Here’s a good example of what I was saying about El Segundo and the relationship we’ve established with them that’s making them nervous sometimes. The hardest hurdle the company had to jump was during the process of switching to the composite interstage was getting that gigantic oven and getting it powered up. The city had to approve it. They have never had to approve anything like that. We obviously lease these facilities—

TSR: Would it be easier if you were your own landlord?

Molina: The Southern California market. It’s been so wonderful. Outrageous.

TSR: When Elon has a Netscape moment, I am sure he will be ready to invest in real estate.

Molina: We’re looking for a few significant milestones coming up in the next year before that comes.

Boland: You cook it to form…

Molina: …to give the strength properties it needs. It is established technology. We didn’t reinvent anything or really create anything new. It is established technology that has been around for quite a while, and that has been used in aerospace for a while. It was the right decision to make for this vehicle. You can get an idea of what it looks like up close.

TSR: You’ll have a half dozen of these. What is the stir welding piece?

“The hardest hurdle the company had to jump was during the process of switching to the composite interstage was getting that gigantic oven and getting it powered up. The city had to approve it. They have never had to approve anything like that.”

Molina: The stir welding we’ll look at in the main building. The Falcon 9 will be the first vehicle completely friction stir welded, I’m told. Friction stir welding, to juxtapose with traditional welding, is a more precise way of doing a weld. The materials come out with more strength properties afterward.

This is the second stage. It is significantly different than the first stage. This is our third production build.

TSR: Who are the owners?

Molina: This is the Malaysians.

TSR: Have they decided where they are going to launch out of yet? Has that been announced yet?

Molina: No, I think it’s still in play. They were interested in seeing how it would work out logistically.

TSR: Are they going to launch a satellite?

Molina: It’s a commercial communications satellite. There’s a quite a bit of heat around the effort. There’s a conference that my boss [Gwynne Shotwell, Vice President of Business Development] went to. She said some of the folks who were janitorial were asking great questions. It was very fascinating for her which she didn’t expect.

TSR: They are much better consumers than we are.

Structural combined LOX, RP-1 tank

Molina: Here’s the first stage tank.

TSR: The tank is the stage, the stage is the tank.

Molina: That’s an interesting nuance. There are a lot of folks who do know rockets are actually confused by that because there are usually multiple tanks that we’re dealing with. When we have this structural LOX tank, they’re like, “What tank goes with this?”

TSR: It has a bulkhead. So less structure than if it was two separate tanks.

Molina: It’s a lot cleaner, a lot simpler.

TSR: You screw in the rocket engine there. What do you screw in at the other end?

Molina: The other end would be open. There are two domes at the either end. The engine goes on one, the interstage goes around here. It allows the parachute to deploy through [the dome hole] and then we recover [the first stage].

The damaged first stage [from the December launch attempt] is on its way back here. We felt the repair work needed to be done in a factory setting and not in 85-degree heat with our folks being sent down there away from there families. It’s coming back here. The second production build that belongs to TacSat has been sent out there.

TSR: Does the Air Force get a break for using a used first stage tank?

Molina: The TacSat, you mean? It’s still not determined which group is going to get which tank.

Transporter

Molina: You can get an idea of what the transporter is. It isn’t too much different than this. It’s basically a cradle, obviously a cradle that needs to absorb some of the shock of transport. It is more complicated than this, but it gives you an idea of the shape of it. It rests in there in the cradle. For the record, it is the same piece of tooling for the launcher as well.

TSR: Going to the Moon, can we launch horizontal? Like Moonraker?

Molina: Not at this point.

Tumlinson: Elon wants to go to Mars, dude, not the Moon.

Next week: Testing


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