A preliminary report on the Jan. 31 plane crash in Northeast Philadelphia found that the cockpit voice recorder didn't record any audio during the accident. Why it matters: The report from federal investigators at the National Transportation Safety Board (NTSB) offers some new insight into the crash that killed seven people but stops short of providing a probable cause.

The preliminary report on the Philadelphia jet crash found the cockpit voice recorder likely hadn't recorded audio for several years.

The National Transportation Safety Board says a cockpit voice recorder was not working on a medical transport plane that crashed in Philadelphia in January and likely had not been working for several years.