Accident Learjet 60 N999LJ,

ASN Wikibase Occurrence # 321634

Date:	Friday 19 September 2008
Time:	23:53
Type:	Learjet 60
Owner/operator:	Global Exec Aviation
Registration:	N999LJ
MSN:	60-314
Year of manufacture:	2006
Total airframe hrs:	108 hours
Engine model:	Pratt & Whitney Canada PW305A
Fatalities:	Fatalities: 4 / Occupants: 6
Aircraft damage:	Destroyed, written off
Category:	Accident
Location:	Columbia Metropolitan Airport, SC (CAE) - United States of America
Phase:	Take off
Nature:	Executive
Departure airport:	Columbia Metropolitan Airport, SC (CAE/KCAE)
Destination airport:	Los Angeles-Van Nuys Airport, CA (VNY/KVNY)
Investigating agency:	NTSB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
A Learjet 60, N999LJ, operated by Global Exec Aviation, overran runway 11 while departing Columbia Metropolitan Airport, SC (CAE). The pilot, copilot, and two of the four passengers were killed; the two other passengers were seriously injured. The aircraft was destroyed by postcrash fire. Visual meteorological conditions prevailed, and an IFR flight plan was filed for the non-scheduled domestic passenger flight to Los Angeles-Van Nuys Airport, CA (VNY).
The beginning of the takeoff roll appeared normal. However, sparks were observed as the airplane traveled along the runway. The airplane then continued beyond the runway and through the approximately 1,000-foot runway safety area and, beyond that, struck airport lighting, navigation facilities, a perimeter fence, and concrete marker posts. The airplane then crossed a roadway and came to rest when it struck an embankment across the road from the airport.
Postaccident examination of markings and tire debris indicated that the right outboard tire failed first because of underinflation, followed by failures of the other tires. Examination of the engines revealed evidence consistent with high thrust in both engines and indicated that the thrust reversers were stowed when the airplane hit the embankment.

The National Transportation Safety Board determines that the probable cause of this accident was the operators inadequate maintenance of the airplanes tires, which resulted in multiple tire failures during takeoff roll due to severe underinflation, and the captains execution of a rejected takeoff after V1, which was inconsistent with her training and standard operating procedures.

Contributing to the accident were (1) deficiencies in Learjets design of and the Federal Aviation Administrations (FAA) certification of the Learjet Model 60s thrust reverser system, which permitted the failure of critical systems in the wheel well area to result in uncommanded forward thrust that increased the severity of the accident; (2) the inadequacy of Learjets safety analysis and the FAAs review of it, which failed to detect and correct the thrust reverser and wheel well design deficiencies after a 2001 uncommanded forward thrust accident; (3) inadequate industry training standards for flight crews in tire failure scenarios; and (4) the flight crews poor crew resource management.

Accident investigation: