Aviation Accident Summaries

Aviation Accident Summary WPR19FA241

Wilkeson, WA, USA

Aircraft #1

N300GG

Glaser Dirks DG 300 ELAN

Analysis

The pilot of the glider had flown for about 1 hour and 20 minutes when he arrived in the vicinity of an airport other than his departure airport and reported to another glider pilot via radio that he was “looking for lift.” Information from an onboard flight recorder indicated that the pilot flew about 4 miles south of the airport before turning back toward the airport; circling several times in areas of lift, but generally descending until arriving over the airport at an altitude of about 565 ft above ground level. Witnesses at the airport saw the glider circling the airport several times before its landing gear was lowered and the glider flew toward the runway. During the landing approach, the glider impacted trees and descended to the ground in a steep, nose-down attitude. Examination of the glider revealed no evidence of preimpact mechanical malfunctions or anomalies that would have precluded normal operation. The circumstances of the accident are consistent with the pilot’s continued circling over the airport in an attempt to find lift. His delayed decision to land resulted in a low landing approach path and subsequent impact with trees.

Factual Information

HISTORY OF FLIGHTOn August 25, 2019, about 1503 Pacific daylight time, an experimental Glaser-Dirks DG 300 glider, N300GG, was substantially damaged when it was involved in an accident near Buckley, Washington. The pilot was fatally injured. The glider was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. Recorded data from an onboard flight computer revealed that the accident flight began at 1327 and ended at about 1503. The data showed that the glider was towed northeast of the departure airport, and the pilot released from the tow airplane about 4,100 ft mean sea level (msl). The pilot flew within this area to the west, followed by a turn to the southwest. The data showed that the glider’s altitude fluctuated between 4,200 ft msl and 2,133 ft msl during the flight. At 1448, about 15 minutes before the accident, the glider was about one-half mile northwest of Burnett Landing Airport (WN15), Wilkeson, Washington (about 8 nautical miles southwest of the departure airport), at an altitude of 3,400 ft msl. The glider continued southwest for about 5 miles and descended to an altitude of about 2,230 ft msl before turning to the northeast toward WN15. During this time, the glider made four separate circling turns, during which its altitude increased slightly before the glider continued to descend. Following the fourth turn, the glider turned left directly toward WN15 at 1,690 ft msl and arrived over WN15 at 1501 at an altitude of 1,365 ft msl, about 565 ft above ground level. The glider circled WN15 about two and a half times while descending. The last recorded data point was located 130 ft south of the accident site at an altitude of about 961 ft msl, or 161 ft agl. The pilot of another glider stated that he did not see the accident glider but communicated with the pilot via radio. During the conversation, the accident pilot informed him that he was down south by the power lines and was “going to where you are going.” About 5 minutes later, the accident pilot stated that he was “going to Burnett.” Later, the accident pilot stated that he was “over Burnett at 1,800, looking for lift.” Multiple witnesses saw the glider arrive and circle over (WN15). One witness watched the glider circle the airport about 3 to 4 times, then the landing gear extended while the glider was behind a stand of trees. The glider banked to the left about 30° to 40°, the left wing impacted a tree, and the glider descended to the runway in a nose-down attitude. The following figure shows the flight route retrieved from the onboard flight recorder. The color variations identify the glider’s proximity to the ground, with dark red identifying the closest proximity to the ground and dark blue depicting the highest altitude above the ground. Figure. Accident route of flight, showing the glider’s altitude 15 minutes before the accident. White arrows point to the direction of travel. WRECKAGE AND IMPACT INFORMATIONThe accident site was located at the approach end of runway 31. The glider was oriented on a heading of 161°. All major components were confined in a debris field of about 30 ft by 30 ft. Examination of the glider revealed no evidence of any preexisting mechanical anomalies or malfunctions that would have precluded normal operation. ADDITIONAL INFORMATIONThe FAA Glider Flying Handbook, Chapter 7, Launch and Recovery Procedures and Flight Maneuvers states in part: Pilots need to determine a proper visual reference point as an initial point (IP) from which to begin the approach for each landing area. The IP may be located over the center of the gliderport/airport or at a remote location near the traffic pattern… the sequence of a normal approach is from over the IP to the downwind leg, base leg, final approach, flare, touchdown, rollout, and stop. Regarding planning off-airport landings during cross-country flights, the publication stated: The most common off-field landing planning failure is denial. The pilot, understandably eager to continue the flight and return to an airport, is often reluctant to initiate planning for an off-field landing because, in the pilot’s mind, to do so probably results in such a landing. It would be better, the pilot thinks, to concentrate on continuing the flight and finding a way to climb back up and fly away. The danger of this false optimism is that there is little or no time to plan an off-field landing if the attempt to climb away does not succeed. It is much safer to thoroughly understand the techniques of planning an off-field landing and to be prepared for the occurrence at any time. Decision heights are altitudes at which pilots take critical steps in the off-field landing process. If the terrain below is suitable for landing, select a general area no lower than 2,000 feet above ground level (AGL). Select the intended landing field no lower than 1,500 feet AGL. At 1,000 feet AGL, commit to flying the approach and landing off field. MEDICAL AND PATHOLOGICAL INFORMATIONToxicology testing performed by the FAA Forensic Sciences Laboratory identified 7.2 ng/ml of carboxy-THC in subclavian blood. It was also identified in urine, as was hydroxy-THC, an active metabolite. No parent THC or active metabolite was found in the pilot’s blood.

Probable Cause and Findings

The pilot’s delayed decision to land following a loss of thermal lift, which resulted in collision with trees during the landing approach.

 

Source: NTSB Aviation Accident Database

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