NTSB: Poor tire maintenance led to 2008 Learjet 60 crash at Columbia, SC

by B. N. Sullivan

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.

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.

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.”

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

More details about the Global Exec Aviation Learjet 60 crash in South Carolina

The U.S. National Transportation Safety Board (NTSB) has updated and expanded information in its preliminary report regarding the fatal Learjet 60 accident at Columbia, SC on September 19, 2008. The accident aircraft was operating as a Part 135 charter by Global Exec Aviation of Long Beach, CA.

The aircraft was departing Columbia Metropolitan Airport (CAE) en route to Van Nuys, CA, when the crew attempted to reject take-off at about 136 knots. The the aircraft subsequently overran the runway, left the airfield, and crossed a highway before coming to rest on an embankment. The accident claimed the lives of the two crew members and two passengers, and seriously injured two other passengers. The aircraft was destroyed by a post-crash fire.

Earlier this month, the NTSB released preliminary findings about the accident. Today a revised Preliminary Report was posted to the NTSB website, providing more detailed information about the accident. Quoting from today's report [NTSB ID DCA08MA098]:

The airplane came to rest along a southeasterly orientation, nose-up on the side of a hill of approximately 25-30 degree slope. With the exception of all three landing gear, right delta fin, and right wing flap, all major airplane assemblies were found in the expected orientations. The top and right side of the fuselage had burned away to about the level of the cabin floor. The aft fuselage was mostly consumed by fire as far aft as the localizer antenna on the vertical stabilizer.

The first piece of tire debris was observed about 2300 feet from the departure end of runway 11. Numerous other piece of tire debris were located along the runway. Prior to the first piece of tire, five small pieces of broken taxiway reflector adhesive were found. Tire and skid marks could be followed on the runway and were spaced 100 inches apart (8’ 4”) consistent with the spacing between the centers of the inboard left and outboard right wheels. Before reaching about 3400 foot of remaining runway, the left and right main gear tire rims scarred the runway surface.

The marks led past the runway and through four rows of gravel at the bases of the instrument landing system antenna components. Approximately 150 feet past the end of the pavement, near the first set of lights, the main landing gear pistons and wheel sets with the brake assemblies were found. The right main landing gear (squat) micro-switch was found on the grass near the main landing gear with short pieces of wire remaining. The left squat switch was also found on the grass, but with no wires.

The wheel sets were found with very little rubber other than tire beads attached. Grinding and friction damage was evident on all wheel and brake assemblies, with the most severe damage on the right outboard, and diminishing somewhat across to the left outboard. The right outboard wheel halves had the edges of both bead flanges ground completely away. The tire beads were missing. The general bottom features of the brake assembly were ground flat and the bottom of the ground area of the assembly exhibited heat-bluing. The hydraulic lines had extensive damage.

Preliminary examination of the right PW305A engine revealed that the accident exposed inlet guide vanes (IGV) and reference to a manufacturer’s chart showed the orientations were consistent with high power. The thrust reversers were in the retracted/stowed orientations.

The main cabin door was found closed and latched. The aft exit and fuselage area was destroyed by fire, however, the exit handle and one pin-type latch were found in debris. Both were in the open or unlatched position. One of the surviving passengers reported no difficulty opening the exit.

The NTSB report also noted that both crew members held Air Transport Pilot certificates with Lear 60 type ratings. The captain had logged approximately 3,140 hours total flight time and approximately 35 hours in the Lear 60 type. The first officer had logged approximately 8,200 hours total flight time and approximately 300 hours in the Lear 60.

According to the NTSB, the aircraft (registration N999LJ) date of manufacture was January 30, 2007. It had logged less than 120 flight hours total.

The operator, Global Exec Aviation, had no prior accidents recorded in the NTSB database.

NTSB Preliminary Report on the Learjet 60 Crash in South Carolina

The NTSB has released a preliminary report on the Columbia, South Carolina Learjet 60 accident last month that claimed the lives of two pilots and two passengers, and injured two other passengers. The NTSB report briefly describes the accident, but does not suggest any cause:

On September 19, 2008, at about 11:53 p.m. EDT, a Learjet Model 60 (N999LJ) operated by Global Exec Aviation as an on-demand passenger flight under 14 CFR Part 135 overran runway 11 while departing Columbia, South Carolina, enroute to Van Nuys, California. The 2 crewmembers and 2 of the 4 passengers were fatally injured, the other 2 passengers suffered serious injuries. The aircraft was destroyed by extensive post-crash fire. Weather was reported as clear with light winds.

Tire debris and portions of airplane components were found along the 8,600 foot runway. According to witnesses and initial information, the beginning of the takeoff roll appeared normal, then sparks were observed as the airplane traveled along the runway. The airplane continued beyond the runway threshold, through the approximately 1,000 foot runway safety area and impacted airport lighting, navigation facilities, perimeter fence and concrete marker posts. The airplane then crossed a roadway, and came to rest on an embankment on the far side of the road. The fire began on the airport side of the roadway. [NTSB ID: DCA08MA098]

The report made no mention of a burst tire, although in a press conference just days after the accident, a spokeswoman for the NTSB said that, based on a preliminary review of the aircraft's Cockpit Voice Recorder (CVR), "The crew reacted to a sound that was consistent with a tire blowout," and apparently initiated a rejected takeoff. Tire debris was reported to have been found on the runway, about 2,800 ft. past the point where the aircraft had begun its takeoff roll.

The investigation is ongoing.

Global Exec Aviation Learjet 60 crash at Columbia, SC

A chartered Learjet 60 operated by Global Exec Aviation, LLC, has crashed at Columbia Metropolitan Airport (CAE), West Columbia, South Carolina. Four of the six people on board, including both crew members, were killed in the accident. Two more passengers were seriously injured. The aircraft was completely destroyed.

According to the U.S. National Transportation Safety Board (NTSB), the aircraft (registration N999LJ) crashed on take-off at 11:53 p.m. EDT on Friday, September 19, 2008. News reports say that the aircraft overran Runway 11 at Columbia Metropolitan Airport, crossed the airport perimeter and came to rest on an embankment along Highway 302. At the time of the accident, the aircraft was departing Columbia for Van Nuys, CA. An airport official who was quoted by local news website TheState.com said that the weather was "cool, dry and clear" when the accident occurred.

All six people who were on board have been identified. A news article about the accident published by television station WIS News 10 reports:

Lexington County Coroner Harry Harman identified all four victims from California. Harman says the pilot, Sarah Lemmon, 31, of Anaheim Hills, co-pilot James Bland, 52, of Carlsbad, Chris Baker, 29, of Studio City and Charles Still, 25, of Los Angeles all perished in the crash.

The two survivors, 32-year-old Travis Barker, former drummer of the band Blink-182, and 35-year-old Adam Goldstein, aka DJ AM, are currently at the Augusta Burn Center.

The airport has been temporarily closed to enable the investigation team to examine evidence on the runway.

WIS News 10 has published a collection of still photos of the crash site.

TheState.com has made an online condolences book available.

Condolences to the family, colleagues and friends of the pilots and passengers who perished in this accident. Best wishes for a full and speedy recovery to the two men who were injured.

UPDATE Sep. 22, 2008: Yesterday Debbie Hersman, an NTSB official, indicated that there was evidence that a tire had burst during the takeoff roll of the Learjet 60 that crashed at Columbia, SC. At a meeting with the press, Hersman said that, based on a preliminary review of the aircraft's Cockpit Voice Recorder (CVR), "The crew reacted to a sound that was consistent with a tire blowout," and apparently initiated a rejected takeoff. Tire debris was found on the runway, about 2,800 ft. past the point where the aircraft had begun its takeoff roll. The runway is approximately 8,600 ft. long.

Today the Associated Press, quoting the chief deputy coroner for Lexington County, reported that the two crew members died from smoke inhalation and burns. Both "were burned on their entire bodies and died within minutes" of the crash. The two passengers who perished are believed to have died on impact, since no evidence of smoke was found in their lungs.

The two surviving passengers suffered second- and third-degree burns, but are expected to recover fully.

[Photo Source]