Comments at a recent meeting of a government advisory board indicate that launch-pad shortages are affecting launch-vehicle economics.

The National Space-Based Positioning, Navigation, and Timing Advisory Board met on August 14-15 in Arlington, Virginia. Aerospace Daily & Defense Report covered the meeting in a recent article.

During the meeting, Vice Chairman Bradford Parkinson made a case for doing multiple launches of GPS satellites on a single rocket. “Our friendly competitors are all doing triple launch. The economics are persuasive. Pressure on launch pads are persuasive. It would just cost a heck of a lot less.”

Launch pad shortages are one reason why SpaceX is looking at building a new launch site in Texas.

Pad shortages are another reason to move away from expendable launch vehicles as quickly as possible. Reusable vehicles can be designed (in fact, must be designed) for rapid turnaround and checkout. They cannot afford to spend weeks or months sitting on a pad the way ELVs do.

The pad problem also favors air-launch systems such as Virgin Galactic’s Launcher One, Paul Allen’s Stratolaunch, ALASA , and many other systems under development. Not all air-launch systems are created equal. Stratolaunch will be constrained, by virtue of its size, to a small number of airports with special runways. That may not be a serious problem, though. The United States built quite a few such airports for the Strategic Air Command, during the Cold War.

Unfortunately, the pad shortage may create a vicious cycle which makes it more difficult to solve the problem.

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