Piper PA28 accident near Walker, Minnesota, September 2, 2020
On September 2, 2020 at about 1:07 am local time, a 1964 Piper PA28, registered N8957W, was substantially damaged in an accident during enroute near Walker, Minnesota (Walker Muni airport). It was a personal flight under general aviation rules (Part 91). 1 person was killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot’s impairment from the effects of an undiagnosed brain tumor.
Source: NTSB aviation accident database, copy made November 2, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 2, 2020 · about 1:07 am local time · cases in 2020
- Place
- Walker, Minnesota · Walker Muni · cases near this airport · map
- Type
- Accident
- Injuries
- 1 person was killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Piper PA28 235, built 1964 · all PA28s on the register
- Registration
- N8957W · no longer on the register · serial 28-10531
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot was on the final leg of a cross-country flight at the time of the accident. A representative of the fixed base operator (FBO) reported that, during a fuel stop after the initial flight leg, the pilot landed without announcing his intentions over the radio. The pilot subsequently requested the airplane be fueled but remained in the airplane and stared straight ahead as it was being fueled. Afterward, the pilot exited the airplane and ate his lunch in the FBO conference room. He was offered a bottle of water but did not acknowledge. During the second flight leg, air traffic controllers observed altitude and course deviations and noted slow radio responses that caused them to be concerned that the pilot was hypoxic or disoriented. They diverted the pilot to an intermediate airport and subsequently declared an emergency on the pilot’s behalf. He was met by emergency medical personnel but refused treatment. The pilot subsequently departed for the intended destination airport without refueling. During the final flight leg, position data depicted the pilot altering course as the airplane approached a line of storms. He proceeded about 15 miles away from the storms but then abruptly reversed course toward the intended destination airport and again approached the line of storms. About 4 minutes before the accident and as the airplane continued to approach the line of storms, the pilot entered a descent from 7,000 ft, which appeared to continue until impact with the surface of a lake. The airplane came to rest in about 12 ft of water. Post-recovery airframe and engine examinations did not reveal any anomalies consistent with a preimpact failure or malfunction. Based on the available information, the airplane flew about 4.5 hours since being fully fueled. However, due to submersion in the lake, no estimate could be made concerning the remaining fuel onboard at the time of the accident. Without additional data, whether fuel exhaustion occurred could not be determined. The pilot was reportedly slow to respond during conversations, sleeping excessively, and seemed to have significant difficulty focusing in the weeks before the accident, which was noted to be unusual for the pilot. His autopsy revealed a previously undiagnosed brain tumor that had a compressive effect on his brain. Based on the autopsy findings and information about the pilot’s behavior on the day of the accident and during the preceding weeks, the pilot was likely impaired by effects of his brain tumor at the time of the accident. The autopsy also identified two peripheral blood clots in the pilot’s left lung and blood clots in the deep veins of his left lower leg. Blood clots in deep leg veins may develop for a variety of reasons, including from slowed blood flow during prolonged sitting and from pro-clotting effects of cancer. However, whether symptoms from the blood clots contributed to the accident could not be determined from available information.
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
- Medical event during enroute defining event
- Collision with terrain or object (not controlled flight into terrain) during enroute
The NTSB's findings
- Personnel issues › Physical › Impairment/incapacitation › Illness/injury › Pilot
Pilot
- Certificate: airline transport pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 8,250 hours in all
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: left
- Injury: fatal
The aircraft
- Airframe total time: 4,733.6 hours
- Last inspection: annual inspection, November 5, 2019; 53 hours since
- Maximum gross weight: 3,000 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-540-B4B5 (piston); 0 hours total
The flight
- Departed from: STC St. Cloud MN at 11:32 pm
- Destination: BJI Bemidji MN
- Flight plan: none
- Runway N/A
Weather at the time
- Light: dusk
- Wind: from 200° at 14 knots, gusting 28
- Visibility: 10 statute miles
- Sky: broken clouds at 7,500 ft; scat at 6,500 ft
- Temperature: 64°F (18°C), dew point 54°F (12°C)
- Altimeter: 29.48 inHg
- Observation at 8:15 pm from Y49, 12 miles away
Weather report (METAR): 020115Z AUTO 20014G28KT 10SM -TSRA SCT065 BKN075 OVC100 18/12 A2948 RMK AO2 LTG DSNT NW THRU NE
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Photographs from the investigation 12 pictures from the NTSB's docket, as the NTSB released them
Photo 1 – Fuselage / Engine / Propeller (Piper Photo)
Photo 2 – Fuselage (Piper Photo)
Photo 3 – Fuselage (Piper Photo)
Photo 4 – Empennage (Piper Photo)
Photo 5 – Left Wing (Piper Photo)
Photo 6 – Left Wing (Piper Photo)
Photo 7 – Right Wing (Piper Photo)
Photo 8 – Right Wing (Piper Photo)
Photo 9 – Engine (Piper Photo)
Photo 10 – Engine (Piper Photo)
Photo 11 – Engine (Lycoming Photo)
Photo 12 – Engine (Lycoming Photo)The NTSB's photographs with the NTSB's captions, at screen size. Open a picture to see it full size or to report one that should not be shown.
Documents from the investigation the NTSB's docket: the evidence folder behind the report
18 documents, released by the NTSB on October 4, 2022. 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.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Meteorology Factual Report | PDF, 28 pages · our copy | View Download |
| 2 | Statement of Party Representatives to NTSB Investigation | PDF, 3 pages · our copy | View Download |
| 3 | Summary of Air Traffic Control Communications | PDF, 3 pages · our copy | View Download |
| 4 | Accident Photos | PDF, 12 pages · our copy | View Download |
| 5 | NTSB Medical Factual Report | PDF, 3 pages · our copy | View Download |
| 6 | Release of Aircraft Wreckage, NTSB Form 6120.15 | PDF, 1 page · our copy | View Download |
| 7 | Airplane Owner's Manual (Excerpt) | PDF, 3 pages · our copy | View Download |
| 8 | ADS-B Data File -- Hez to Irk (#1) | data file · our copy | Download |
| 9 | ADS-B Data File -- Irk to STC (#2) | data file · our copy | Download |
| 10 | ADS-B Data File -- Departure from STC (#3) | data file · our copy | Download |
| 11 | ADS-B Data File -- Final Flight Segment (#4) | data file · our copy | Download |
| 12 | Plot of Airplane Position Data | PDF, 4 pages · our copy | View Download |
| 13 | Statements -- Fixed Base Operators | PDF, 2 pages · our copy | View Download |
| 14 | Statement -- Pilot's Friend | PDF, 1 page · our copy | View Download |
| 15 | Statement -- St Cloud Fire/ems | PDF, 1 page · our copy | View Download |
| 16 | Toxicological Report | PDF, 1 page · our copy | View Download |
| 17 | Airplane Examination Summary | PDF, 4 pages · our copy | View Download |
| 18 | Statement -- Pilot's Brother | PDF, 2 pages · our copy | View Download |
Connections how this case links to the rest of the register
- N8957W: not on the register today · the record of its deregistration
- Piper PA-28 Cherokee, Warrior, Archer and Arrow 18,639 registered today · the model family and its accident history
- Piper 44,848 aircraft on the register
- Engine: Lycoming O-540-B4B5 40 aircraft carry this series today · as the NTSB recorded it
- Walker Municipal · nearest airport
- St. Cloud Sky Central Airport · departed from
- Bemidji Regional · bound for
- Accidents and incidents in Minnesota 1,544 since 1982 · 209 in the last ten years
- Minnesota 6,939 aircraft registered
The whole map of how records connect · these connections as data: /graph/accident/CEN20LA374.json.
The bigger picture in Aviation Analytics: accidents over time since 1982, by model, by phase of flight and conditions, by place and on the map.
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 does not name anyone involved, its policy at this time. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.
