Cessna 172N accident near Grass Valley, California, September 19, 2021
On September 19, 2021 at about 10:30 pm local time, a 1979 Cessna 172N, registered N4977G, was substantially damaged in an accident during landing near Grass Valley, California (Nevada County airport). It was a personal flight under general aviation rules (Part 91). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot’s failure to attain a proper touchdown point on the runway while landing in gusting wind conditions, which resulted in a runway overrun. Contributing to the accident was the pilot’s distraction due to an electrical issue.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 19, 2021 · about 10:30 pm local time
- Place
- Grass Valley, California · Nevada County · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 172N, built 1979 · all 172Ns on the register
- Registration
- N4977G · no longer on the register · serial 17273524
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that, he departed normally to fly the airport traffic pattern. After he turned to the base leg of the traffic pattern, he observed a low voltage indication on the annunciator panel and was unable to announce his base turn on the radio. The pilot then turned to the final approach leg of the traffic pattern without making the announcement on the radio and added three notches of flaps. He experienced “windshear” near the runway threshold and the airplane briefly ascended. The pilot attempted to regain his glide path by extending full flaps and the airplane floated down the runway. At the time he was concerned about climbing out, so he elected to continue the landing instead of performing a go-around. After the airplane eventually touched down on the runway, the pilot applied full braking, but the airplane skidded off the runway edge into a ditch, which resulted in substantial damage to the right wing. According to the pilot, he misjudged the landing distance and landed long to salvage the landing instead of attempting a go-around. He further remarked that the electrical issue affected his radio and prevented him from announcing his base and final turns in the airport traffic pattern, which may have influenced his decision to land promptly. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.
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
- Electrical system malf/failure during approach (VFR pattern final)
- Collision during takeoff/land during landing defining event
The NTSB's findings
- Aircraft › Aircraft systems › Communications system › (general) › Malfunction
- Personnel issues › Psychological › Personality/attitude › Motivation/respond to pressure › Pilot
- Personnel issues › Action/decision › Info processing/decision › Decision making/judgment › Pilot
- Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Descent/approach/glide path › Not attained/maintained
- Environmental issues › Conditions/weather/phenomena › Wind › Gusts › Effect on operation
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 293 hours in all; 243 in this make and model; 47.3 as pilot in command
- Last flight review: January 7, 2021
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 3,491 hours
- Last inspection: annual inspection, September 17, 2021; 1 hours since
- Maximum gross weight: 2,300 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-320-H2BD (piston); 3,983 hours total
The flight
- Flight plan: none
- Runway 07/2, 4,657 ft by 75 ft
Weather at the time
- Light: daylight
- Wind: at 0 knots, gusting 11
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 66°F (19°C), dew point 43°F (6°C)
- Altimeter: 30.10 inHg
- Observation at 3:35 pm from KGOO
Weather report (METAR): KGOO 192235Z AUTO 00000G11KT 10SM CLR 19/06 A3010 RMK A01
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
4 documents, released by the NTSB on October 12, 2021. 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 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 9 pages | View Download |
| 2 | Correspondence with Accident Pilot | PDF, 3 pages | View Download |
| 3 | Record of Conversation, Accident Pilot | PDF, 1 page | View Download |
| 4 | Accident Photograph | PDF, 1 page | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
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.