Maintenance Eyed In N.C. Crash

Investigators looking for the cause of a plane crash that killed 21 people said Thursday that a recently adjusted tail assembly controlling the plane's lift was moving erratically during the 37 seconds the doomed flight was in the air.

The up-and-down motion began after the plane underwent routine maintenance Monday night and showed up during all seven flights before Wednesday's crash, said John Goglia, a National Transportation Safety Board member.

The flight data recorder pulled out of the smoldering wreckage confirmed the erratic movement was also present just before the crash.

A team of NTSB investigators was sent to the Raytheon Aerospace facility in Ceredo, W.Va., where the maintenance was done.

"We need to know which procedures were followed," Goglia said.

The Federal Aviation Administration also told Air Midwest officials to check 45 planes serviced at the facility. Air Midwest, a commuter airline of the Mesa Group, operates as US Airways Express in some areas.

"It's pretty clear that Air Midwest needs to take immediate action," FAA spokesman Greg Martin said.

Also, as CBS News Correspondent Bob Orr reports, the twin engine Beech 1900 was within 100 pounds of its maximum weight when it took off. With the rear heavier than the front, investigators say, the nose began rising sharply to a perilously steep angle.

The pilots were unable to push the nose down and control the plane. The data recorder suggests a jam of the elevators, the flat surfaces on the rear of tail wing that move a plane up and down.

The tail of the plane underwent maintenance on Monday in Huntington, West Virginia, just two days before the crash. Investigators now are focusing on those maintenance procedures which involved the replacement of a key elevator part and the adjustment of the cables that control it.

After that maintenance, Orr reports the plane flew seven short trips. While the flight data recorder picked up "erratic elevator movements" on each of those flights, there were no control problems and no complaints from pilots before the plane crashed on the eighth flight in Charlotte.

US Airways Express Flight 5481 crashed in flames moments after leaving the Charlotte airport, killing the 19 passengers and two crew members aboard. Capt. Katie Leslie reported an emergency to the tower, but the FAA said the transmission was cut off before she could identify the problem.

Information from the flight data recorder shows the flight took off with its nose up 7 degrees, which is normal. But the pitch increased sharply, to 52 degrees, by the time the plane reached 1,200 feet. The plane soon rolled to the right and headed toward the ground.

"Something occurred to drive that pitch angle to 52 degrees," Goglia said. "That is abnormal."

The data recorder also shows the elevator control on the tail of the Beech 1900 "moving up and down a lot" on all eight flights it took following the maintenance work, Goglia said.

Elevators are flaps that swing up and down from the rear of a plane's horizontal tail stabilizer, increasing or decreasing lift. In the case of Flight 5481, Goglia said the maintenance workers replaced a tab that controls movement of the elevator and adjusted the tension of the cable controlling the tab.

The erratic motion may not have affected earlier flights if the plane was not loaded to capacity and there were no reports of problems from Tuesday's flights, Goglia said. But the twin-engine turboprop was at nearly full weight when it took off from Charlotte for Greer, S.C.

Jonathan Orenstein, chief executive of Mesa Air Group, said the work done on the plane in West Virginia was performed by Raytheon Aerospace LLC. He said the airline was already looking for other planes that may have been worked on by the same maintenance crew.

Officials at the facility in West Virginia referred calls for comment to company headquarters in Madison, Miss. There, spokesman Chris Blount said only that Raytheon works under contract to Mesa for maintenance on its Beech 1900 fleet.

Frank Graham, an aviation investigator and former pilot, said the fact the pitch of the plane's nose reached 52 degrees hints at an extreme problem.

"This is a very unusual, significant, catastrophic failure that would allow the nose of the aircraft to pitch up to 52 degrees," he said. "It sounds a little bit like the reverse of the Alaska Airlines 261 crash, where a component in the tail failed and aircraft pitched down and no matter what the pilots did they couldn't regain control."

In that January 2000 crash, the NTSB concluded that shoddy maintenance of the MD-80 jetliner led to the failure of a tail component that helps move the stabilizer. The crash killed 88 people.

The FAA has issued nearly two dozen airworthiness directives on the Beech 1900-D since 1994, warning problems that must be repaired if found in an aircraft. A directive issued in November warned that screws in the elevator balance weight attachment could come loose and interfere with the horizontal stabilizer.

Goglia said the final victims were removed from the wreckage Thursday and family members were expected to visit the site Friday.