WASHINGTON, May 9 (Reuters) - The U.S. Commerce

Department said Friday it has opened a national security

investigation into the import of commercial aircraft, jet

engines and parts.

The investigation, which was opened on May 1 but not

publicly disclosed previously, seeks public comment within three

weeks on a series of comments on "the impact of foreign

government subsidies and predatory trade practices on the

competitiveness of the commercial aircraft and jet engine

industry."