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Accidents · NTSB WPR22FA023 · Final report

Mooney M20M accident near Snoqualmie, Washington, October 28, 2021

On October 28, 2021 at about 4:11 pm local time, a 1993 Mooney M20M, registered N40KA, was substantially damaged in an accident during enroute (climb to cruise) near Snoqualmie, Washington. It was a personal flight under general aviation rules (Part 91). 1 person was killed. The weather was instrument conditions (cloud, fog or low visibility).

The NTSB's probable cause their words, unchanged

The pilot’s decision to fly the airplane into known icing conditions, which resulted in a loss of airplane control and collision with terrain.

Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.

What the record shows

Date
October 28, 2021 · about 4:11 pm local time
Place
Snoqualmie, Washington · map
Type
Accident
Injuries
1 person was killed.
Weather
instrument conditions (cloud, fog or low visibility)
Aircraft
Mooney M20M, built 1993 · all M20Ms on the register
Registration
N40KA · no longer on the register · serial 27-0171
Damage
Substantial damage
Flight
Personal flight · general aviation rules (Part 91)

The NTSB's narrative final · quoted from the NTSB record

After a 6-year hiatus from flying, the pilot had just purchased the airplane. The morning of the accident flight, he filed an instrument flight rules (IFR) flight plan and received a weather briefing that identified icing conditions along the planned flight route. The pilot departed the airport about 0842 and planned to climb to an altitude of 17,000 ft mean sea level (msl). About 0901, the controller cleared the pilot to depart 14,000 ft msl and climb to 17,000 ft msl. Subsequently, the controller informed the pilot of multiple PIREPs for icing conditions from 12,000 ft msl to 18,000 ft msl and offered the pilot an altitude of 19,000 ft msl to get above the icing, which the pilot accepted. About 0904, after climbing to an altitude of 16,300 ft msl, the airplane began a rapid descent with a series of tight spiral turns. Communication between the controller and the pilot became broken and unreadable. An airplane operating in the area relayed to the controller that the pilot reported being out of control. Shortly after 0910 radar contact was lost, and the airplane impacted terrain. It is likely that the accident airplane encountered structural icing and that the erratic turns coupled with a rapid descent rate were indicative of the pilot’s loss of airplane control, which resulted in a collision with terrain. Postaccident examination of the engine and airframe revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The supplement to the pilot’s operating handbook and the airplane flight manual contained a warning that stated, “INTENTIONAL FLIGHT INTO KNOWN ICING IS PROHIBITED.” The pilot’s logbook contained no record of a recent instrument proficiency check.

The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.

The factual record from the NTSB's investigation tables, in plain English

What happened, in order

  1. Structural icing during enroute (climb to cruise) defining event
  2. Loss of control in flight during enroute (climb to cruise)

The NTSB's findings

  • Personnel issues › Action/decision › Info processing/decision › Decision making/judgment › Pilot
  • Environmental issues › Conditions/weather/phenomena › Temp/humidity/pressure › Conducive to structural icing › Effect on equipment
  • Environmental issues › Conditions/weather/phenomena › Temp/humidity/pressure › Conducive to structural icing › Effect on operation
  • Personnel issues › Task performance › Use of equip/info › Aircraft control › Pilot

Pilot

  • Certificate: private
  • Ratings: single-engine land; instrument: airplane
  • Flight time: 1,561.4 hours in all; 5.1 in this make and model
  • Last flight review: January 11, 2006
  • Medical certificate: Class 3 (with waivers/limitations)
  • Seat: unk
  • Injury: fatal

The aircraft

  • Last inspection: annual inspection, September 22, 2021; 2,435.8 hours since
  • Maximum gross weight: 2,740 lb
  • Seats: 4
  • Landing gear: retractable
  • Engine: Lycoming TIO-AF1B (piston); 0 hours total
  • Fire on the ground
  • Operator: Another Greaser LLC

The flight

  • Departed from: AWO Arlington WA at 3:42 pm
  • Destination: TWC Twin Falls ID
  • Flight plan: IFR

Weather at the time

  • Light: daylight
  • Wind: from 190° at 13 knots
  • Visibility: 3 statute miles
  • Sky: broken clouds at 1,300 ft
  • Temperature: 57°F (14°C), dew point 55°F (13°C)
  • Altimeter: 29.99 inHg
  • Observation at 9:02 am from KSEA, 29 miles away

Weather report (METAR): KSEA 281602Z 19013KT 3SM R16L/5000VP6000FT -RA BR BKN013 OVC021 14/13 A2999 RMK AO2 RAB1558 P0001 T01440128

Injuries

FatalSeriousMinorNone
Flight crew1

Documents from the investigation the NTSB's docket: the evidence folder behind the report

13 documents, released by the NTSB on May 3, 2023. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.

#DocumentWhat it is
1 Meteorology Factual Report PDF, 37 pages · our copy View Download
2 Meteorology Attachment 1 - Flight Track PDF, 9 pages · our copy View Download
3 Meteorology Attachment 2 - ForeFlight Weather Briefing PDF, 35 pages · our copy View Download
4 N40KA Flight Track and Communication video · our copy View Download
5 Pilot's Logbook PDF, 16 pages · our copy View Download
6 Annual Inspection Date and Notes PDF, 1 page · our copy View Download
7 Certification of Party Representative PDF, 14 pages · our copy View Download
8 Memorandum for Record -previous Owner PDF, 1 page · our copy View Download
9 Memorandum for Record -witness PDF, 1 page · our copy View Download
10 Autopsy Memorandum for Record PDF, 1 page · our copy View Download
11 Accident Site and Wreckage Photographs PDF, 4 pages · our copy View Download
12 Wreckage and Examination Report PDF, 8 pages · our copy View Download
13 Wreckage Release Form PDF, 1 page · our copy View Download

The same docket at the NTSB.

Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.