Pilot Said He Was Struggling With Mountain Wave Activity

The preliminary report released by the NTSB concerning a fatal accident in Wyoming last month indicates that the airplane went down after the pilot reported mountain wave activity. The pilot and his three passengers were all fatally injured in the accident.

NTSB Identification: WPR11FA032
14 CFR Part 91: General Aviation
Accident occurred Monday, October 25, 2010 in Lander, WY
Aircraft: MOONEY M20J, registration: N201HF
Injuries: 4 Fatal.

This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed.

On October 25, 2010, about 1352 mountain daylight time (MDT), a Mooney M20J, N201HF, collided with mountainous terrain near Lander, Wyoming. The airplane became the subject of a week-long search after it was lost from ground-based radio communications and radar tracking facilities about 45 minutes after it departed from Jackson Hole Airport (JAC), Jackson Hole, Wyoming, on October 25, 2010. On the afternoon of November 1, 2010, the wreckage was located by ground searchers at the 11,100-foot level in the Wind River mountain range, Wyoming. The instrument rated owner/pilot and three passengers were fatally injured and the airplane sustained substantial damage. Instrument meteorological conditions likely existed at the location and time of the accident. The personal flight was operated under the provisions of Title 14 Code of Federal Regulations (CFR) Part 91, on an instrument flight rules (IFR) flight plan and clearance to Pierre, South Dakota.

According to information provided by representatives from Lockheed Martin (LM) and the Federal Aviation Administration (FAA), on the morning of the accident, the pilot obtained his initial telephone weather briefing about 0920 MDT. About 1040, he telephoned again, obtained an abbreviated weather briefing, and filed an IFR flight plan. The flight plan included a planned departure time of 1130, and a destination of Rapid City Regional Airport, (RAP) Rapid City, South Dakota. The filed route of flight was Dunoir (DWN) very high frequency omni-range (VOR) navigation facility, Boysen Reservoir (BOY) VOR, Muddy Mountain (DDY) VOR, and then direct to RAP. About 1237, the pilot used the Internet to file another IFR flight plan, which again specified JAC as the origination airport. The filed departure time was 1247, and the filed route was DNW VOR, Riverton (RIW) VOR, DDY VOR, Newcastle (ECS) VOR, Rapid City (RAP) VOR, and Philip (PHP) VOR. The destination was Pierre Regional Airport (PIR), Pierre, South Dakota, and the filed altitude was 9,000 feet. Both weather briefings included AIRMETs (Airmen's Meteorological Information) for mountain obscuration, turbulence, and icing along the planned flight routes and altitudes.

Mooney M20J File Photo

The airplane departed JAC just after 1300, and was in communication with and tracked by FAA air traffic control (ATC) at Salt Lake City Air Route Traffic Control Center (ARTCC). The first radar target was recorded about 1309, and the airplane was tracked until about 1336, when it was at an altitude of 14,000 feet. About 1341, the pilot filed a pilot report via radio, which stated that he was at 14,000 feet, and was encountering light chop, and a trace of rime icing. The airplane was re-acquired by ground radar about 1346, still at the same altitude. About 1352, the last radar target associated with the airplane was recorded, with an indicated altitude of 13,300 feet. Shortly before that, the pilot radioed to ATC that he was unable to maintain altitude due to mountain wave activity.

According to information provided by the Fremont County Sheriff's Office, ground searchers located the wreckage at an elevation of 11,100 feet on a scree slope about 6 miles southeast of Gannett Peak. The wreckage exhibited significant crush and impact damage. The right wing was partially fracture-separated from the fuselage, and the propeller blades were fracture-separated from the propeller hub. All components were located within 20 feet of the main wreckage.

The pilot held a private pilot certificate with airplane single land and instrument airplane ratings. The airplane was first registered to him in January 2010. It was manufactured in 1977, and was equipped with a non-turbocharged Lycoming IO-360 series engine.

FMI: www.ntsb.gov