N169GL

HISTORY OF FLIGHT

On September 1, 2013, at about 1310 mountain daylight time (MDT), Great Lakes Airlines flight 7125, a Beechcraft 1900D, N169GL, suffered a left main landing gear collapse during landing on runway 27 at Telluride Regional Airport (TEX), Telluride, Colorado. The two flight crew members and 10 passengers were not injured and the airplane sustained substantial damage. The scheduled passenger flight was operating under 14 Code of Federal Regulation Part 121 and originated from Denver International Airport (DEN), Denver, Colorado.

The first officer was the pilot flying and the captain was the pilot monitoring. Takeoff, climb, and cruise were normal.

At 1231, the crew selected landing gear down and observed a problem with the left main landing gear. The captain began the "Failure of Landing Gear to Extend Normally" checklist and noted that both green left landing gear down and locked lights were not illuminated and the landing gear circuit breaker had tripped.

At 1240, the captain began the "Landing Gear Manual Extension" checklist and advised maintenance control via radio through Telluride operations that there was no green left gear down and locked indication, the red in transit light was illuminated, and the circuit breaker had tripped. Telluride operations relayed a message from company dispatch asking if the crew could consider diverting to Farmington, NM (FMN) for landing. After discussing fuel burn, safety concerns, and the Airport Rescue and Fire Fighting (ARFF) capabilities at Telluride, the crew decided landing at Telluride was the best option and advised operations accordingly.

At 1247, the captain attempted to pump the landing gear down in accordance with the checklist and reported to the first officer that the landing gear extension handle would not move.

At 1250, the captain began the "Gear Up Landing" checklist and then proceeded with the "Planned Emergency Preparation" checklist. He contacted Telluride Unicom to request ARFF services and briefed passengers regarding the situation.

At 1259, the captain began the "Landing with One Main Up or Unsafe" checklist and after preparing for landing, the crew conducted the approach and landing on runway 27. During the landing roll, as the airplane slowed through about 80 knots, the left main landing gear collapsed. The airplane stopped on runway 27 at 1309 and the crew initiated an evacuation.

INJURIES TO PERSONS

There were no injuries to the 10 passengers or 2 crewmembers on board.

DAMAGE TO AIRCRAFT

The airplane received substantial damage, coming to rest on the nose landing gear, the right main landing gear, and the left wingtip. The left wingtip lower skin suffered abrasion damage, the left inboard flap was deformed and wrinkled and the trailing edge and aft nacelle were abraded where they contacted the ground. The left outboard flap was deformed and wrinkled and the trailing edge was abraded. The left aileron had abrasion damage to the outboard 2 feet of trailing edge and lower trailing edge skin. The left ventral strake was damaged along its lower edge where it contacted the ground. The left engine inboard machined mount fitting was fractured and portions were separated. The firewall was deformed and bent. The left engine and propeller were also damaged.

PERSONNEL INFORMATION

The flight crew consisted of two pilots and the accident occurred on their first flight of the day.

The captain, age 32, reported 5,800 hours total flight time, including 4,700 hours as pilot in command and 3,000 hours in the BE-1900 at the time of the accident. The captain held a valid Federal Aviation Administration (FAA) Airline Transport Pilot (ATP) certificate with type ratings for EMB-120 and BE-1900, and a current FAA first-class medical certificate with a limitation requiring that he must wear corrective lenses.

The first officer, age 30, reported 2,576 hours total flight time, including 1,350 hours pilot-in-command, and 1,350 hours in the BE-1900 at the time of the accident. He held a valid FAA ATP certificate with a type rating for the BE-1900 and a current FAA first-class medical certificate with no limitations or waivers.

AIRCRAFT INFORMATION

N169GL, manufacturer serial number UE-169, was a Beech 1900D equipped with two Pratt and Whitney PT6A-65B turbo-prop engines. The company reported that the airplane had logged 35,184 hours total time on the airframe at the time of the accident. Recorded data and airline records indicated no open maintenance items with the airplane.

Landing Gear System

The airplane is equipped with a retractable tricycle landing gear system. Extension and retraction of the nose landing gear (NLG) and the two main landing gear (MLG) is accomplished by the action of individual hydraulic actuators installed on each landing gear assembly. The MLG actuators retract for gear extension and extend for gear retraction while the NLG actuator extends for gear extension and retracts for gear retraction. Hydraulic pressure for the system is supplied by a hydraulic power pack located in the left wing leading edge inboard of the engine nacelle.

The hydraulic system has a nominal operating pressure of 3,000 psi and includes a system relief valve that will open automatically to prevent over pressurization and damage.

Landing Gear Controls and Indications

The landing gear control selector handle was located on the captain's side of the cockpit on the lower right subpanel and included two positions: UP and DOWN. The control handle must be pulled out of a detent before it can be selected either UP or DOWN. When the handle is placed in either the UP or DOWN position, a hydraulic pump motor is activated and a solenoid allows hydraulic fluid to flow to the appropriate side of the actuators. When the landing gear are fully extended, an internal mechanical lock in each actuator holds the landing gear in the down position, and activates a switch that removes power from the hydraulic pump.

Landing gear position indication is provided by six green lights; two for each of the nose and the left and right main gear, on the subpanel adjacent to the landing gear control selector handle. The two green lights for the left main landing gear are labeled "L" and "H". Two red in transit lights are provided on the landing gear control selector handle which illuminate when the landing gear control has been selected and any of the landing gear are not either fully extended or fully retracted.

A landing gear relay circuit breaker is located on the pilot's right sub panel to protect the system from electrical overload. The relay circuit breaker will trip open if the landing gear does not reach the down and locked position after the hydraulic pump motor has run continuously for about 16 seconds.

Manual Landing Gear Extension

An alternate landing gear extension handle is located on the floor on the pilot's side of the flight deck. To engage the manual extension system, the landing gear control lever must be in the down position, the landing gear relay circuit must be pulled and the handle is then pumped until the green gear down annunciators are illuminated.

Maintenance History

Review of maintenance records indicated the left main landing gear actuator was purchased by Great Lakes Airlines and sent for overhaul in August 2011. At that time, a component upgrade included replacement of the end cap and Lee plug in addition to the standard overhaul parts. The actuator was received from the overhaul facility in September 2011 and installed on the accident airplane in March 2012.

Since the installation of the left main gear actuator, landing gear problems were noted in the airplane logbook in June 2012, September 2012, and July 2013. The most recent maintenance issues documented in July 2013 included three separate instances in which the landing gear would not retract when commanded. These discrepancies were corrected by performing maintenance on the landing gear safety switches.

Flight Crew Procedures

The Quick Reference Handbook (QRH) includes the following abnormal procedures; Failure Of The Landing Gear To Extend Normally, Landing Gear Manual Extension, Landing With One Main Up Or Unsafe and, Planned Emergency Preparation. These procedures include guidance to pull the landing gear relay circuit breaker, the landing gear warning horn circuit breaker, and the TAWS (Terrain Awareness Warning System) circuit breaker. The Landing With One Main Up Or Unsafe procedure includes a step directing the landing gear alternate extension handle should be pumped "…until maximum resistance is felt. Do not stow".

METEOROLOGICAL INFORMATION

Day visual meteorological conditions prevailed at the time of the accident. The Telluride Airport surface observation at 1255 MDT, the most recent observation at the time of landing, reported wind from 260 degrees at 9 knots gusting to 16 knots, visibility 10 statute miles, 6,500 feet broken, 11,000 feet overcast, temperature 20 degrees Celsius, dew point temperature 8 degrees Celsius, and altimeter 30.43 inches mercury.

AERODROME INFORMATION

The Telluride Regional Airport (TEX) is located about 5 miles west of the city of Telluride, CO. The airport has 2 runways for commercial and general aviation. Runway 27 is asphalt, 7,111 feet long, 100 feet wide with a touchdown zone elevation of 9,070 feet above mean sea level. The runway is served by a precision approach path indicator system (PAPI) with a 4 degree glide path on the left side of the runway.

FLIGHT RECORDERS

The cockpit voice recorder (CVR), an L-3/Fairchild model FA2100-1020, serial number 000694648, was removed from the airplane and downloaded at the NTSB Vehicle Recorder Laboratory. The cockpit voice recorder contained 2 hours, 4 minutes of recording on 4 audio channels. The audio quality of the channels containing information from the captain's and first officer's audio panels, and public address system were each characterized as exce...