Aviation Accident Summaries

Aviation Accident Summary CHI04LA155

Waukegan, IL, USA

Aircraft #1

N77DK

Mitsubishi MU-2B-40

Analysis

The aircraft was substantially damaged during a hard landing, which subsequently collapsed the nose landing gear and wrinkled the fuselage. The pilot stated that the approach was "fairly" stabilized, however, he noted he was late getting set-up for landing. He did not recall how many green landing gear extension lights he observed prior to landing. The pilot reported that when the main landing gear touched down on landing the nose of the aircraft "immediately dropped to the runway." He reported that the aircraft came to rest headed straight down the runway, approximately on the centerline. The post-accident examination determined that the nose landing gear was in a retracted position in the wheel well. The remaining sections of the nose landing gear doors were wedged behind the landing gear strut. The lower, outboard section of the fuselage was wrinkled from the nose landing gear to a point approximately even with the windshield. The aircraft manufacturer stated that the nose landing gear doors are mechanically actuated.

Factual Information

On June 15, 2004, at 1324 central daylight time, a Mitsubishi MU-2B-40, N77DK, piloted by a commercial pilot, sustained substantial damage during landing on runway 23 (6,000 feet by 150 feet, asphalt) at Waukegan Regional Airport (UGN), Waukegan, Illinois. The personal flight was operating under 14 CFR Part 91 on an instrument flight rules flight plan. Visual meteorological conditions prevailed at the time of the accident. The pilot and passenger were not injured. The flight originated from the Oakland County International Airport (PTK), Pontiac, Michigan, approximately 1230. The pilot provided information concerning the accident during a phone interview and in a written statement. He reported that the weather was clear as the flight was inbound to UGN. He noted that the active runway was 5, however, he requested and was subsequently cleared to land on runway 23. The pilot stated that the approach as "fairly" stabilized, however, he noted he was late getting set-up for landing. He reported that he looked for the green landing gear extension lights, but did not recall how many he observed prior to landing. He noted that the aircraft was configured with three green lights, one for each gear assembly, and one red light to indicate an unsafe gear condition. The pilot stated that the aircraft was "on speed" as the main landing gear touched down. He reported that when the main gear contacted the runway, the nose "immediately dropped" and went "straight down". He noted that the nose landing gear was retracted in the well wheel after the accident. He stated that after the aircraft's nose contacted the runway pavement, the engines were still running. He shut them down and exited the aircraft. He reported that the aircraft came to rest headed straight down the runway, approximately on the centerline. The post-accident examination determined that the nose landing gear was in a retracted position in the wheel well. The tires exhibited worn areas consistent with skidding on pavement. Scrape marks were present on the nose skin immediately forward of the wheel well. A portion of the left nose gear door remained attached to the hinge and was wedged behind the landing gear assembly. A section of the right gear door remained attached to the hinge. The inboard edge of the door section was also wedged behind the gear assembly. The lower, outboard section of the fuselage was wrinkled from the nose landing gear to a point approximately even with the windshield. The aircraft manufacturer stated that the nose landing gear doors are mechanically actuated. When the nose landing gear retracts, a coupler contacts the gear strut and the linkage closes the doors. Upon gear extension, a "bungee" assembly opens the doors when the strut releases the coupler and linkage. Winds recorded by the UGN Automated Surface Observing System at 1255 were from 070 degrees at 5 knots. Recorded winds at 1355 were from 060 degrees at 7 knots.

Probable Cause and Findings

The pilot's misjudgment of the landing flare which resulted in a hard landing. Contributing factors were the subsequent overload and collapse of the nose landing gear.

 

Source: NTSB Aviation Accident Database

Get all the details on your iPhone or iPad with:

Aviation Accidents App

In-Depth Access to Aviation Accident Reports