Special investigation report
Subtitle: air traffic control system
By: National Transportation Safety Board.
Publisher: The Board; National Technical Information Service, distributor]
Published: 1981
Place of publication: Washington, D.C; [Springfield, Va
Language: eng
Number of pages: 56
Subjects: Air traffic control -- United States.
Other titles: Air traffic control system.
Notes: Cover title.

"NTSB-SIR-81-7."