By Allison Lampert
(Reuters) -As a bell sounded in the cockpit, three UPS pilots tried to control a cargo flight that crashed this week in Louisville, Kentucky, killing at least 13 people, the National Transportation Safety Board said on Friday.
While UPS flight 2976 started uneventfully, a repeating bell was heard on the aircraft's flight cockpit voice recorder just 37 seconds after the crew called for takeoff thrust, NTSB member Todd Inman told reporters.
The bell persisted until the end of the recording
25 seconds later, which Inman believes signals the aircraft's crash.
"During this time, the crew engaged in efforts to attempt to control the aircraft before the crash," Inman said.
CRASH DESTROYED TWO BUSINESSES
The independent U.S. safety agency is leading the probe into the crash of the 34-year-old MD-11 freighter at the Louisville airport. The plane reached about 100 feet (30.5 meters) above ground level before plunging in flames off the runway and destroying two businesses.
One of the plane's three engines detached from the left wing as it rolled down the Louisville airport runway.
The bulk of the left engine pylon, a structural component connecting the aircraft engine to the wing or fuselage, was still attached to the left engine when it separated from the wing, Inman said.
"Now, subsequently, there could be damage that occurred upon its impact with the terrain," he said.
Debris from the engine, an area of focus to investigators, was found on the runway.
Investigators are also probing the aircraft's maintenance history, including a six-week period this fall when it underwent heavy maintenance at a San Antonio, Texas, repair facility.
A transcript of the cockpit voice recorder, which contained two hours and four minutes of good quality digitally recorded audio, will be made public in several months, Inman said.
Air crashes are normally caused by multiple factors, with a preliminary report generally expected 30 days after the incident.
(Reporting By Allison Lampert in Montreal. Additional reporting by Dan Catchpole in SeattleEditing by Rod Nickel)
