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Highway bridge
What do highway bridges have to do with developing suborbital launch vehicles? A lot, if you plan to haul that vehicle anywhere. (credit: MorgueFile)

Interview: two guys at the vanguard (part 3)

Fast turns

The Space Review: Tell me about DC-X’s fast turnaround time.

Earl Renaud: I think it was X-A flight 3. They were ready for a second flight eight hours after they landed. They didn’t go because the weather turned ugly and they scrubbed and launched the next morning. So it was 24 hours turnaround they demonstrated, but they were ready to go after eight. We want to beat that by a factor of two, which means we really, really have to pay attention to what we are doing and what it takes to do inspection and turnaround. That’s ultimately what’s going drive everything; the more people that touch the vehicle, the more people I gotta pay.

Let’s analyze the operations math on the DC-X. They had about 15 people working on it. Fifteen people at $100,000 a year, that’s $1.5 million you need just for your ground crew. If you’re really only gonna charge $100,000 a flight, that’s—

TSR: 15 extra flights.

Renaud: 15 flights just to support your ground crew. These numbers add up very quickly.

TSR: That’s with 100% margin.

Renaud: That’s not counting what it costs to keep those guys in the field. That’s just salary. That’s a low-paid guy with insurance and all the benefits, $100,000.

TSR: Someone who’s only taking home $50,000 a year.

Renaud: Your not flying some place that guy can commute from. Which means he’s going to want to come home every weekend.

TSR: Now he’s an ex-pat—

Renaud: You’ve got him in a hotel. He’s charging his meals.

TSR: I lived that way. You spend another $80,000-$100,000.

That’s ultimately what’s going drive everything; the more people that touch the vehicle, the more people I gotta pay.

Renaud: All of a sudden that $100,000 guy becomes a $200,000 guy and in reality those 15 guys are $3 million. All of a sudden it gets very expensive very fast. Pat was once discussing in a bar why people thought the space shuttle cost so much to fly. They were bemoaning the fact that despite what NASA says, it’s a billion dollars a flight. The shuttle program is $5 billion per year and they fly five times per year on average. Then somebody said, “It’s the people, stupid! Tens of thousands of people in five countries all with a charge line open to the project.”

Pat [Bahn, TGV CEO] said, “You know, if I could get it down to two guys and my van, we could make some money!” Everybody laughed. Then they scratched their heads and said, “What can you do with a small ground crew?” That’s where the concept came from.

TSR: So why didn’t DC-X get adopted?

Renaud: What killed the DC-X was not Clinton’s line-item veto. What killed the DC-X was that they only built one. It fell over and burned. It wasn’t even that bad of an accident. The engines were still good, the avionics was still good, some of the helium bottles didn’t even burst, and the landing gear was still good.

TSR: Three-fourths of it?

Renaud: The landing gear didn’t break. That was an operational failure. It was a gas pressurized system. You had to disconnect the line to retract it and then you reconnect it so that when it’s pressurized it deploys. Their checklist was interrupted. It was an operational problem. They pulled one out and didn’t reconnect it. That kind of thing is going to happen in a flight test program. If they had more test vehicles, they could have continued the program as a suborbital program and scraped up the money to fund incremental improvement to get the vehicle to orbit.

TSR: So McDonnell Douglas was ready to say “forget it” after the vehicle fire?

Renaud: They didn’t want to salvage the DC-X program by pursuing a profitable suborbital vehicle. When the DC-X was killed, Pat went back and said, “Do you care if I do this? If I pick up this concept and run with it?” They said, “Knock yourself out, babe.” Pat said, “I want to go do this.” He started TGV with the idea of taking that concept and doing whatever improvements he thought were necessary to improve the operability even more and make money out of it and use it as a reusable sounding rocket.

Going mobile

Renaud: If you really want to go after the suborbital market, you to be operate where people want you to operate, because it’s a local asset. Which means you’ve got to be mobile. Which means that you’ve got to take the system to the customer. Which means “yes, you are going to be on the road.”

TSR: Now you’re going to have to fit it inside one of these big cargo planes.

Renaud: It’s got to go down the road.

TSR: Right, you’ve got to be able to do intermodal.

Renaud: What’s the minimum bridge height on the Interstate? 13.5 feet [4.1 meters]. You know why Gary Hudson built and flew the Roton ATV at Mojave?

TSR: Because he couldn’t take it anywhere.

Renaud: He was going to do it at Moffett [Field, California]. They had Scaled Composites build the base for that vehicle as one huge piece of carbon structure. And they got it built down there. Burt said, “Sure, I’ll take your money and I’ll build it.” Pat, how big is the base on the Roton.

TSR: I saw the building.

Bahn: It’s larger than an Antonov-225. It’s too big to fit in the An-225 plane.

Renaud: It’s too big to fit in the Antonov. So the only way it could get anywhere is by helicopter. It’s a wind sail. If that thing is under there and the wind starts to take it, a helicopter can’t hold it. The helicopter pilot said, “Sure, but the minute the wind gets above ten knots, we’re cutting the wire.” And all of a sudden they couldn’t get it out of Mojave.

Bahn: The estimate was if they spent nine months campaigning with the helicopter and crew, they could find enough wind windows that they could get little micro hops.

Renaud: Get a sky crane and you could fly it for 25–50 miles [40–80 km]. Then that vehicle takes a couple days of maintenance. So you do it again. So Gary picked up his whole team and moved it to Mojave.

TSR: It’s like the Spruce Goose.

If you want to fly it, you want take it out of the United States, it had better either fit in a cargo container, or fit on deck on a cargo ship if it doesn’t fit in a container.

Renaud: When we first said when we were at the Space Frontier Foundation [Conference], we were talking about our vehicle requirements. One of our high-level requirements is that it go down the expressway. Somebody came up and said, “That’s the dumbest thing I have ever heard in my life. You’re going to design a launch vehicle that can go down the expressway and that’s one of your high-level constraints. That’s the dumbest thing they ever heard.” That guy came back to us about four years later and said, “You know, you got this long before any of us did.”

TSR: Eisenhower got it in the fifties. He built his road network so he could transport his ICBMs around.

Renaud: It’s got to go down the highway! That’s why we have a 13.5-foot bridge height.

TSR: Why has it taken 50 years for everybody else to figure this out?

Renaud: If anybody tells you that they are designing a launch vehicle that’s going to be mobile or it’s going to have low-cost ops and it’s on a trailer that’s taller than 13.5 feet? It isn’t going to make it.

TSR: Elon Musk got his Falcon to Washington, DC.

Renaud: It’s not wider than 13 feet.

TSR: So basically that’s it.

Renaud: That’s one of your constraints. If you want to fly it, you want take it out of the United States, it had better either fit in a cargo container, or fit on deck on a cargo ship if it doesn’t fit in a container.

There are limits to what the cranes can lift to put it on deck. Or it can go on a RO/RO [roll on/roll off ship designed for wheeled cargo] if you can fit on the bridge on the back RO/RO. Or it has to go in a cargo aircraft.

On here I have the loading diagram for the C-17. I know what volume and load I can get up the ramp, turn and get under the wing spar.

TSR: And you’ve got your trucks too?

Renaud: You betcha. And I have a rail map on here. I have the maximum width and height for every rail line in the US and Canada. You have to look at that stuff.

TSR: That’s amazing.

Renaud: How are you gonna move it? You have to look at that stuff up front, because you can’t do it later. If you design your vehicle 14 feet [4.25 meters] wide, you’re never going to be able to squeeze it down again.

TSR: It’s like the Spruce Goose in The Aviator. They had to cut all the [power transmission] wires to get it out to Long Beach. It was just sitting there for years.

Renaud: Ask [XCOR CEO] Jeff Greason. He took the EZ-Rocket to Oshkosh. It wouldn’t fit on the truck. If he hadn’t taken the wings off, it wouldn’t fit on the truck. They found if they tilted it, it fit the envelope barely, but that just was a fluke.

TSR: They also said at Space Access, when they arrived at Oshkosh they didn’t have insurance when they got there. They had to get a binder on site.

When you say, “What’s your insurance cost,” they should say, “First, second, or third party liability?”

Renaud: That’s when Jeff got religion. “I have to pay attention to transportation, operability, insurability.” It’s nice to watch these guys get religion. Operations and operability is something that you really have to look at from day one. It has to be your mantra. It has to be the only thing you talk about. It has to be your entire life. Getting people from aerospace, traditional aerospace, to stick to that is really, really tough.

TSR: They are going to be thinking, “I really need this flight performance.”

Renaud: Ask any aerospace engineer how you make something better, every time their version of better will be flight performance. It’s a built-in bias.

TSR: For the people trying to do carbon abatement, they’re trying for energy security by hydrogen. It has great performance characteristics. It’s so clean.

Renaud: Hydrogen is a wonderful fuel.

TSR: Except that you can’t mine it. You’ve got to build it, in which case you are energy negative. So what you’ve described is that there’s a short play for every VTHL HTVL, every vehicle that is too big—

Renaud: Do you know how to separate the people who are going to be successful from the people who aren’t? Ask them to describe their business. If they start out with talking about propellant, taking about their apogee, talking about their carrying capacity or passengers or payload or flight rating or anything else, “Bye.” Pat’s phrase is, “Amateurs talk propulsion, professionals talk insurance.” It’s absolutely true. When you go to a company and go, “What’s your insurance going to cost?” They go, “I don’t know.” People spend billions of dollars without this simple screening. When you say, “What’s your insurance cost,” they should say, “First, second, or third party liability? Business and casualty loss, business [interruption], which one?” They’ll have numbers for all of those.

TSR: I am actually writing an academic paper that puts this out for everybody if you want your flight costs low you’ve got to get your range costs down and your insurance costs down.

Renaud: In ’99 we started screaming to the Space Frontier Foundation. In ’99 we started giving talks on insurance. We started going “Hey, insurance is going to kill the business.” It wasn’t until last year that every body else started going “Hey, you know, if we buy insurance, we’re not going to get there.” People were going to different government agencies going, “We need money to build things.” And we were going to different government agencies going—

TSR: We need relief from insurance.

Renaud: “Can we put together a common risk pool? Can we do something about common liability and pooling assets?” And everybody’s going, “What are you talking about?” That’s the way to separate the men from the boys.


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