The U.S. National Transportation Safety Board (NTSB) has reached a determination of probable cause concerning the September 2008 crash of a Learjet 60 at Columbia Metropolitan Airport (CAE), West Columbia, South Carolina. The aircraft (registration N999LJ), operated by Global Exec Aviation, LLC, overran runway 11 at CAE during a rejected takeoff, following a tire failure. The aircraft crashed and burned, killing four of the six people on board. The NTSB concluded that the probable cause of this accident was "the operator’s inadequate maintenance of the airplane’s tires, which resulted in multiple tire failures during takeoff roll due to severe underinflation, and the captain’s execution of a rejected takeoff (RTO) after V1, which was inconsistent with her training and standard operating procedures."The NTSB has provided this summary of the accident events:
On September 19, 2008, at 11:53 p.m. EDT, a Bombardier Learjet Model 60 (N999LJ) operated by Global Exec Aviation and destined for Van Nuys, California, overran runway 11 during a rejected takeoff at Columbia Metropolitan Airport.In a statement to the press, NTSB Chairman Deborah A.P. Hersman said, “This entirely avoidable crash should reinforce to everyone in the aviation community that there are no small maintenance items because every time a plane takes off, lives are on the line.”
After the airplane left the departure end of runway 11, it struck airport lights, crashed through a perimeter fence, crossed a roadway and came to rest on a berm. The captain, the first officer, and two passengers were killed; two other passengers were seriously injured.
The investigation revealed that prior to the accident the aircraft was operated while the main landing gear tires were severely underinflated because of Global Exec Aviation’s inadequate maintenance. The underinflation compromised the integrity of the tires, which led to the failure of all four of the airplane’s main landing gear tires during the takeoff roll.
Shortly after the first tire failed, which occurred about 1.5 seconds after the airplane passed the maximum speed at which the takeoff attempt could be safely aborted, the first officer indicated that the takeoff should be continued but the captain decided to reject the takeoff and deployed the airplane’s thrust reversers. Pilots are trained to avoid attempting to reject a takeoff at high-speed unless the pilot concludes that the airplane is unable to fly; the investigation found no evidence that the accident airplane was uncontrollable or unable to become airborne.
The tire failure during the takeoff roll damaged a sensor, which caused the airplane’s thrust reversers to return to the stowed position. While the captain was trying to stop the airplane by commanding reverse thrust, forward thrust was being provided at near-takeoff power because the thrust reversers were stowed. The Safety Board determined that the inadvertent forward thrust contributed to the severity of the accident.
The Safety Board also found that neither the Federal Aviation Administration nor Learjet adequately reviewed the Airplane’s design after a similar uncommanded forward thrust accident that occurred during landing in Alabama in 2001. While the modifications put into place after the Alabama accident provided additional protection against uncommanded forward thrust upon landing, no such protection was provided for a rejected takeoff.
Those who are interested can find much more detailed information about this accident investigation by following the links below:
Accident Report Synopsis, including itemized conclusions, statement of probable cause, and safety recommendations
Cockpit Voice Recorder Transcript - 40-page 'pdf'
NTSB Accident Docket where you can find links to all materials pertinent to this investigation.
Photos of the Accident Scene - WISTV.com
Earlier posts on AircrewBuzz.com about this accident:
- Global Exec Aviation Learjet 60 crash at Columbia, SC - Sep. 20, 2008
- NTSB Preliminary Report on the Learjet 60 Crash in South Carolina - Oct. 9, 2008
- More details about the Global Exec Aviation Learjet 60 crash in South Carolina - Oct. 22, 2008
