The airline said it is sharing its plans for the locking device with other U.S. carriers.

CNN: American Airlines strengthening cockpit doors

In the first place, locking in specific reductions for U.S. forces prior to the conclusion of the ongoing Nuclear Posture Review is putting the cart before the horse.

WSJ: Arms Control Amnesia

The BP deal guarantees Sempra gas at a discount to the price on the U.S.-Mexico border, locking in a nice spread.

FORBES: Gas Guzzler

Symyx moved quickly to secure patents, locking up the field of high-speed materials combination in the U.S. Dow and ExxonMobil dropped plans to develop their own tools when they bumped up against Symyx's patents.

FORBES: Technology

But Andrew Mellon, the U.S. secretary of the Treasury, bought "The Annunciation" with 20 other Hermitage paintings before locking them away in a basement near his Washington home.

WSJ: Jan van Eyck | 'The Annunciation' | Old Subject, New Approach | Masterpiece | By Richard Cork