Throughout the roughly four hours after the jet dropped from civilian radar screens, these people said, the link operated in a kind of standby mode and sought to establish contact with a satellite or satellites. These transmissions did not include data, they said, but the periodic contacts indicate to investigators that the plane was still intact and believed to be flying.
(Follow the latest developments in the search for missing Flight 370.)
Investigators are still working to fully understand the information, according to one person briefed on the matter. The transmissions, this person said, were comparable to the plane "saying I'm here, I'm ready to send data.