MUNICH — U.S. industry officials are concerned that the technical documentation for Europe’s Galileo navigation system is not being shared openly, a concern that Galileo managers say is unfounded.

The United States and the European Union in 2004 agreed to make their respective satellite navigation systems, GPS and Galileo, interoperable so that user equipment can be made inexpensively to benefit from both satellite constellations.

U.S. and European Commission satellite navigation managers met in January in Washington and produced a statement reaffirming that the two sides intend “to maintain a level playing field in the global market for goods and services related to space-based PNT” or positioning, navigation and timing, according to the statement, released here March 6.

But some U.S. navigation-equipment builders see signs that Europe wants to favor its own industry with respect to Galileo technical information.

Michael Swiek, executive director of the U.S. GPS Industry Council, said U.S. companies are being treated like foreigners entering a Japanese restaurant.

“The menu in English has 12 items, and the menu in Japanese, 52 selections,” Swiek said here March 7 during the Munich Satellite Navigation Summit 2007. “You ask what the other menu items are and are told, ‘You wouldn’t like those items, they’re not for you.’ This is the impression that Galileo is creating. We are concerned about license requirements, royalty payments and other inhibitors.”

European officials say part of the problem is that Galileo’s technical specifications have been slow to develop. Any lack of transparency, they say, is because the European Space Agency (ESA), which is Galileo’s technical manager, has preferred to hold off the release of technical-interface documents until the final version is ready, according to Tony Pratt of Britain’s Defence Science Technology Laboratory.

“ESA wants these things to accurately reflect the state of play,” Pratt said in explaining the slow public release of Galileo technical specifications.

Tony Murfin, vice president for business development of NovAtel Inc. of Calgary, Canada, a builder of navigation equipment, said ESA should release even temporary technical data more quickly to permit companies like his to begin preparing to incorporate Galileo into their gear.

“The slippage in the Galileo schedule is really bad,” Murfin said. “My message is: Release it, build it, sell it. Other navigation systems from Japan, India and China are coming, and believe me they will not have all these problems.”

The GPS-Galileo Working Group on Trade and Civil Applications has yet to hear of any concrete examples of refusal to share technical data with U.S. companies, according to David A. Turner, of the U.S. Commerce Department ‘s Office of Space Commercialization.

“This is something we do discuss and that we are watching,” Turner said March 8. What our European counterparts have told us is encouraging, and the recent release by ESA of the Galileo Interface Control Document is a positive sign. Up to now we have not seen any breach of the agreement we have with Europe. But again, it is something we will be keeping a close eye on.”