N213WQ

HISTORY OF FLIGHT

On April 7, 2012, about 1108 central daylight time, a Colgan Air Inc. Bombardier De Havilland DHC-8-402, N213WQ, operating as United Express flight 4915, landed with the nose gear retracted on runway 9 at George Bush Intercontinental / Houston Airport (IAH), Houston, Texas. There were no injuries to the 31 passengers and 4 crewmembers onboard and the airplane received substantial damage. The flight was operating under the provisions of 14 Code of Federal Regulations (CFR) Part 121 as a regularly scheduled passenger flight from Adams Field Airport (LIT), Little Rock, Arkansas.

The first officer was the pilot flying and the captain was the pilot monitoring for the flight. During climb out after departure from LIT the first officer and the captain noticed a different airflow noise than normal when the landing gear was selected up. They observed an amber nose gear door open advisory light, a master caution, and a landing gear inoperative caution light. The three green gear indication lights and three red gear indication lights were extinguished indicating the landing gear was retracted. The captain performed the Nose Gear Door Malfunctions check list contained in the Quick Reference Handbook and the crew maintained airspeed of at or below 185 knots for the remainder of the flight as stated in the checklist.

During the flight to IAH, the crew heard a "thump" and observed the nose gear door amber status light and the LDG GEAR INOP caution light had extinguished.

In accordance with the Nose Gear Door Malfunctions check list, and guidance received from company maintenance and system operations control via ACARS (Aircraft Communications Addressing and Reporting System), the crew elected to use the Alternate Landing Gear Extension checklist for landing at IAH.

The crew exchanged roles as the captain became the pilot flying and the first officer assumed the role of pilot monitoring for the remainder of the flight. Approximately over the ROKIT intersection, about 50 miles from IAH, the first officer began to perform the Alternate Landing Gear Extension checklist.

At 1533:34 the first officer pulled the main gear release handle and the nose gear release handle and observed that the main landing gear indicated down and locked with green indicator lights, the nose landing gear did not indicate down and locked, and the red Nose Gear Unsafe light was illuminated. The alternate gear indication lights in the floor near the nose gear release handle agreed with the primary gear indication lights on the flight deck panel.

After the Alternate Gear Extension Procedure was completed, the crew could hear the nose gear door was "flapping loosely". The flight crew conducted a low approach and air traffic control tower personnel advised them that the nose gear doors appeared to be open but the nose gear did not appear to be down.

At 1556:52 the captain briefed the cabin crew members and advised them that an evacuation, if necessary, would be conducted using the forward doors. The flight crew configured the airplane for landing at flaps 35 on runway 9 with the main landing gear down, and the nose landing gear retracted.

At 1607:46, after passing through about 1,000 feet on approach, the first officer made a "brace" call over the passenger address system. The main gear touched down at 1608:50 and the captain held the nose off the runway until the airplane slowed to about 80 knots. Once the nose touched down, there were sparks and smoke resulting from the fuselage scraping the runway and the airplane came to a stop at about 1609. The captain ordered an evacuation and the pilots performed the On Ground Emergencies checklist. The passengers and crew evacuated through the forward cabin doors and were bussed to the terminal.

INJURIES TO PERSONS

There were no injuries to the 31 passengers or the 4 crewmembers on board.

DAMAGE TO AIRPLANE

The airplane was substantially damaged by deformation and abrasion due to runway contact. The lower forward fuselage was dragged along the runway resulting in structural damage to the fuselage skin, stringers, and frames. The skin on the lower fuselage was worn through to structure creating a large hole in the area between Fuselage Stations X-124 to X-69. The forward nose landing gear doors were torn away from the fuselage. The aft nose landing gear doors were in the closed position with portions of the exterior surfaces scraped and worn down to the honeycomb.

PERSONNEL INFORMATION

The flight crew consisted of two pilots and two flight attendants.

The captain, age 34, was hired by Colgan Air, Inc. in February 2006 as a captain on the Beechcraft BE-1900. He transitioned to captain on the Saab SF-340 in 2007, and then to the DHC-8 in April, 2011. At the time of the accident, he was based in Houston, Texas.

The captain reported approximately 6,500 hours total time, including about 5,000 hours as pilot-in-command and 396 hours in the DHC-8. There were no records or reports of any previous aviation incidents or accidents involving the captain and a search of the National Driver Register found no record of driver's license suspension or revocation.

The captain held a valid Federal Aviation Administration (FAA) Airline Transport Pilot (ATP) certificate with type ratings for BE-1900, SF-340, and DHC-8 and a current FAA first-class medical certificate with a limitation that he must wear corrective lenses. The captain indicated he was wearing corrective lenses at the time of the accident. Training and proficiency checks were current and the company reported that the captain had no record of failures during company training events.

The first officer, 24 years old, was hired by Colgan Air, Inc. in October 2010. He was based in Houston, Texas and commuted to work from Minneapolis, Minnesota. He reported approximately 2,100 hours total flight time and about 900 hours in the DHC-8; all of which was second-in-command time. The were no records or reports of any previous aviation incidents or accidents involving the first officer and a search of the National Driver Register found no record or driver's license suspensions or revocations. He held a valid FAA commercial pilot certificate with an instrument rating and a DHC-8, SIC privileges only, type rating, and an FAA first-class medical certificate.

The first officer's training and proficiency checks were current and the company reported he had no failures recorded during company training events.

The captain and first officer had not flown together previously. The accident occurred on the second leg on the first day of a four day trip.

AIRCRAFT INFORMATION

N213WQ, manufacturer serial number 4213, was a Bombardier De Havilland DHC-8-402 equipped with two Pratt and Whitney PW150A turbo-prop engines. The company reported that the airplane had approximately 7,936 hours total time on the airframe. Recorded data and airline records indicated no relevant maintenance issues with the airplane. At the time of the accident the estimated landing weight was 50,136 pounds.

Landing Gear System

The landing gear is electrically controlled, hydraulically operated and mechanically locked. The main landing gear (MLG) retracts aft into the nacelles and the nose landing gear (NLG) retracts forward into the nose section. The landing gear is operated by the No. 2 hydraulic system. It is controlled by the landing gear selector lever on the landing gear control panel in the flight deck. There is an alternate means of extension for the landing gear in the event that the primary system is not functioning. Advisory lights in the flight deck provide extension and retraction information to the flight crew.

The alternate extension system can be used to extend the landing gear when the No. 2 hydraulic system is not serviceable. The system can also be used if the normal extension system fails to lock the landing gear in the down position.

The alternate extension system is a self-resetting, cable actuated design. Access to the alternate extension system is through the flight compartment. The alternate extension system includes a bypass valve to isolate the landing gear hydraulics from the No. 2 hydraulic system. A manual hand pump hydraulic system is available to assist in locking the main landing gear into the down and locked position.

The alternate extension mechanically releases the NLG forward doors, the MLG aft doors, and all landing gear uplocks are mechanically opened. The NLG free falls to the down and locked position, assisted by the airflow. The MLG freefalls and, if required, are pumped to the locked position by the alternate extension actuators.

Landing Gear Alternate Extension

To isolate the normal landing gear selector valve during flight, a landing gear inhibit switch is installed in the flight compartment ceiling. To use the alternate extension system, the landing gear inhibit switch must first be set from normal to inhibit.

The landing gear alternate release handle, accessed via the landing gear alternate release door in the ceiling of the flight deck compartment, is pulled to open the MLG doors and release the MLG uplocks. Tension springs in the MLG door mechanism pull the doors open and the MLG freefalls into the down position. Springs installed on the MLG stabilizer brace move the lock links into the down and locked position. A hand pump located in the flight compartment floor can be used to fully extend the MLG if necessary.

The landing gear alternate extension handle in the flight deck compartment floor is pulled to release the NLG. The first stage of the pull unlocks the NLG forward doors. Tension springs in the NLG door mechanism assist to pull the doors open. As the handle is pulled further, the NLG uplock is released. The NLG free falls to the fully extended position. Springs installed on the NLG drag strut move the lock links into the down and locked position.

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