FREMONT, Calif., Aug. 28 /PRNewswire-USNewswire/ -- The following is being released by the National Air Traffic Controllers Association:

A subcontractor's mistake caused the FAA Telecommunications Infrastructure (FTI) system to shut down Wednesday morning for 20 harrowing minutes at one of the country's largest regional air traffic control centers, leaving more than half the controllers on duty without the ability to communicate with airborne aircraft or use landline telephones to communicate with other air traffic control facilities.

Controllers at Oakland Center were forced to contact surrounding FAA facilities with their personal cell phones and coordinate instructions to aircraft that were relayed by these facilities over the emergency radio frequencies. Oakland Center is responsible for a huge swath of airspace encompassing most of the northern half of California and parts of western Nevada, in addition to many millions of miles of airspace over the Pacific Ocean.

Today, 48 hours after the communications outage, air traffic controllers are asking these important questions:

-- Why has the FAA put the maintenance work for this critical communications system in the hands of a series of subcontractors, instead of having FAA employees do the work?

-- Why weren't air traffic controllers told on Tuesday of the maintenance work and the fact that redundancy in the system was on its very last thread, thereby making it imperative that the facility be put on some type of alert status?

-- What level of confidence should controllers have in the work of these subcontractors that so directly impacts the safety of the flying public?