NTSB Factual Report

On March 17, 2009, about 1526 mountain daylight time, a Gates Learjet Corporation Learjet 55 airplane, C-GCIL, was substantially damaged during an aborted takeoff at the Natrona County International Airport (CPR), Casper, Wyoming. The captain, the first officer who was flying the airplane, and two passengers were not injured. The airplane was registered to and operated by Sunwest Aviation LTD., Calgary, Alberta, Canada, under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and an instrument flight rules (IFR) flight plan was filed for the cross-country flight. The flight was originating at the time of the accident with an intended destination of Lafayette, Louisiana.

The captain reported that the flight was initially performing a takeoff from runway 3 (a 10,165-foot long asphalt runway). About one-third of the way down the runway, between 60 to 100 knots, he heard the tower controller notify them that he thought he saw smoke originating from the left engine. The captain stated that he immediately called for an aborted takeoff and the first officer initiated the aborted takeoff sequence, "using normal breaking and thrust reverser deployment for a few seconds and continued using thrust reversers only." The flight crew exited the runway onto taxiway Alpha 6, and subsequently performed an engine power check with no anomalies noted. The flight crew then taxied back to Alpha 1 via taxiway Alpha. The captain further stated that he "had no reason at this time to suspect hot breaks due to the minimal use" and "elected to taxi for another takeoff." The captain reported that following a 4 to 5 minute taxi time, the first officer conducted a second takeoff.

The captain further reported that during the second takeoff roll on runway 3, between 80 knots and "prior to the V1 call," the flight crew heard and felt a bang as the airplane yawed to the right. The captain called for a second aborted takeoff. As the first officer initiated the second aborted takeoff, a second bang and additional yaw was noted. The captain took control of the airplane, and maintained directional control with reverse thrust and nose wheel steering. The captain further stated that they were able to slow the airplane down and exit the runway onto taxiway Alpha 7. Upon opening the cabin door, they observed a fire near the left main landing gear and immediately evacuated the airplane. The Airport Fire and Rescue team arrived shortly after and extinguished the fire.

The first officer reported that during the initial takeoff, about one-third of the way down the runway and shortly after the "80 kt call, the tower controller made a call over the tower frequency that he thought he saw smoke coming from our engine." The first officer stated, "The captain called for an aborted takeoff, and I immediately commenced a rejected takeoff, using normal braking and maximum thrust reversers. Within a few seconds, I let off the brakes and used thrust reversers to approximately 60 knots, where I returned to using brakes at taxi speed."

The first officer further stated that during the second takeoff, between 80 knots and V1, she heard and felt a bang, followed by a yaw to the right. Following the captain's call to abort the takeoff, "I commenced the rejected takeoff and maintained directional control, only to hear a second bang and harder yaw to the right."

Examination of the airplane by a Federal Aviation Administration (FAA) inspector revealed that the left main landing gear exhibited fire damage. A punctured hole within the right side of the fuselage was observed just aft of the cockpit.

A post-accident check of the runway by the Casper Airport Public Safety Department revealed that numerous amounts of tire debris extended from the area of taxiway Alpha 4 to Alpha 7.

The Cockpit Voice Recorder (CVR) was retrieved from the airplane and sent to the National Transportation Safety Board's (NTSB) Vehicle Recorder Division for inspection.

The CVR recorded 31 minutes and 56 seconds of usable audio information. The recording revealed that about 16 minutes and 2 seconds after power was applied to the airplane, the flight crew began preparing for flight. At 19 minutes, 27 seconds, the captain requested clearance to taxi from the ground controller. About 2 minutes, 43 seconds later, the captain requested clearance for takeoff from the tower controller. The flight was cleared for takeoff 8 seconds later. During the takeoff sequence, about 8 seconds after the first officer responded to the captain's call of "eighty knots," the tower controller transmitted "appears you have a lot of smoke coming out your engine." At 23 minutes, 28 seconds, the captain called for a rejected takeoff. About 37 seconds later, the first officer stated "the right brake felt funny."

Following the aborted takeoff, the captain decided to run up both engines as the first officer was heard briefing the passengers. At 24 minutes, 45 seconds, the tower controller transmitted "it appears the smoke was from the left engine." At 26 minutes, 1 second, the captain requested clearance to taxi to runway 3. At 27 minutes, 18 seconds, the captain stated "both engines are pulling full power" immediately followed by a comment that it was not a high-speed abort since the "aircraft was only through ninety knots."

At 28 minutes, 34 seconds, the tower controller cleared the flight for takeoff a second time on runway 3. The sound of increasing engine noise was identified at 29 minutes, 11 seconds, followed by an "eighty knots" call at 29 minutes, 25 seconds. Two loud noises, about one second apart were heard beginning at 29 minutes, 34 seconds. At 29 minutes, 36 seconds, the captain called for a rejected takeoff, followed by the first officer stating "blew a tire."

The flight crew reported that at the time of the accident, the airplane weighed 20,772 pounds.

The Learjet 55 Aircraft Flight Manual (AFM), Section 3, "Emergency Procedures," page 36, states "if rejected takeoff was made at weight above the landing maximum brake energy weight as determined from the applicable LANDING WEIGHT LIMITS chart in Section V, the High Energy Stop Inspection (Chapter 5, Learjet Maintenance Manual) must be performed."

The Learjet 55 AFM, Section 5, "Performance Data," page 65, Maximum Landing Weight, states in part "the maximum landing weight (design structural limit for landing) is 17,000 pounds.

According to a Bombardier Learjet representative, using the following conditions: temperature 48 degrees Fahrenheit, altitude: 5,530 feet mean sea level, wind: from 030 degrees at 5 knots, runway: runway 3 (0.1 percent gradient), the maximum brake energy weight was calculated to be 20,300 pounds.

The Learjet 55 AFM, Section 1, "Limitations," page 13, part "TURN-AROUND LIMITS - Aircraft 55-003 thru 55-076 when not incorporating AAK 55-82-6" states in part "if the turn-around weight limit for brake energy, as determined from the applicable LANDING WEIGHT LIMIT chart (Figures 5-54 and 5-55) in Section V, is exceeded during a landing or rejected takeoff, the following limitations must be observed: The aircraft must be parked for a minimum waiting period of 30 minutes before the next takeoff attempt can be made. After the waiting period is observed, a visual inspection of the main gear tires, wheels, and brakes for condition must be made." The operator of the aircraft reported that the accident airplane was equipped with the AAK 55-82-6 modification, therefore, the 30 minute waiting period did not apply.

NTSB Probable Cause

The flight crew's failure to follow the manufacturer’s aircraft flight manual emergency procedures following a rejected takeoff that required a high energy stop inspection. Contributing to the accident was the flight's exceedence of the aircraft's maximum brake energy weight.