Just as an air bag bursts open on impact, cellular phones in cars could someday be programmed to automatically dial 911 to report an accident.
Researchers at Johns Hopkins University say the technology they are working on could help in situations like a June crash in which a Baltimore County woman was trapped in a pickup for four days with a broken neck before she was found.
The system would link a cellular phone with satellites already used for military and civilian navigation in airplanes and at sea, to give authorities the location of an accident.
Researchers said the system could be ready in three years. Delco Electronics in Kokomo, Ind., is working on a similar project that could be released commercially in two to three years, company spokesman Robert Leggat said.