Intelligent Machines

The Crowded Skies

Feb 22, 2011

Spaceports are being built around the United States to facilitate a wave of space tourists, with six nonfederal spaceports already licensed in locations including New Mexico and Oklahoma. From these ports, companies such as Virgin Galactic and Blue Origin plan to operate spacecraft that will provide tourists with at least a peek above the atmosphere. That is causing a headache for the U.S. Federal Aviation Administration, which has to figure out how to integrate space flights into the national air traffic control system.

The problem is that pilots launching into space or returning home cannot make sudden changes in their craft’s altitude and direction in response to an air traffic controller: after an initial rocket boost, most designs are unpowered, gliding or parachuting back to Earth. To avoid the potential for disaster, these flights have been conducted in “sterile airspace,” which establishes a zone from which other aircraft are forbidden.

To date, because space launches are relatively infrequent, it has been possible to establish these zones as needed. But daily flights from multiple locations will necessitate a more systematic approach. The FAA began thinking about this issue in the late 1990s, and last August it established an industry-academic-government Center of Excellence for Commercial Space Transportation to develop new air traffic control rules (and settle other regulatory issues) for the commercial space industry.

Technical developments may also help. For example, Sierra Nevada’s Dream Chaser is designed to use hybrid rockets for powered flight after reëntry, potentially allowing at least limited air traffic control.