National Transportation Safety Board and FBI investigators scour the field north of the Birmingham-Shuttlesworth International Airport where UPS flight 1354 crashed Wednesday. / Frank Couch AP
Federal investigators say the pilots of a UPS cargo plane that crashed in Alabama on Wednesday were warned their descent was too steep, but that air-traffic controllers didn't receive a similar warning.
Robert Sumwalt, a member of the National Transportation Safety Board, said Friday that a cockpit warning sounded the alarm "sink rate, sink rate," which signals a descent that the equipment considered too steep.
"There was an audible warning enunciating "sink rate, sink rate" and that was 16 seconds prior to the end of the recording," Sumwalt said.
But Sumwalt said the air-traffic controller on duty didn't get a similar warning from his ground equipment called a "minimum safe altitude warning." Investigators will try to determine why the Airbus A300-600F's alarm sounded and the ground alarm didn't.
Sumwalt said the experienced controller witnessed the crash.
"He saw what appeared to be a bright spark flash, which he equated to what it would look like if a power line broke," Sumwalt said. "And that was followed by a bright orange flash, according to the controller, and then a red glow."
The first sound of impact is heard 9 seconds before the recording ends, but it's not clear whether the collision is with trees or the ground. Investigators will analyze the tape to determine what it represents.
"We should be able to understand exactly what that sound was," Sumwalt said.
Flight 1354 from Louisville, Ky., crashed in a fireball about 6 a.m. while approaching Birmingham-Shuttlesworth International Airport. The plane hit trees about a half-mile short of the runway before striking the ground and breaking into pieces that skidded hundreds of yards.
Both crew members died: Capt. Cerea Beal Jr., 58, of Matthews, N.C., and co-pilot Shanda Fanning, 37, of Lynchburg, Tenn.
The nearly north-south Runway 18 can be tricky for pilots because of hills at the northern end where the UPS plane went down. The runway, 7,000 feet long, is also shorter than the main east-west runway of 12,000 feet, which was closed for maintenance.
The investigation could take a year or longer to determine what caused the crash. Sumwalt said another briefing is expected Saturday.
"We are just in the very early stages of this investigation," Sumwalt said. "Right now we're just gathering data and we'll start poring over all of that."
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