Cessna 172K accident near Grass Valley, California, January 20, 2004
On January 20, 2004 at about 2:25 am local time, a Cessna 172K, registered N99LR, was destroyed in an accident near Grass Valley, California (Nevada County Airport). It was a personal flight under general aviation rules (Part 91). 2 people were killed. The weather was instrument conditions (cloud, fog or low visibility).
The NTSB's probable cause their words, unchanged
the pilot's continued visual flight into instrument meteorological conditions and failure to maintain an adequate terrain/object clearance altitude. Also causal was the pilot's improper in-flight decision to return to the origin airport in the face of deteriorating weather conditions instead of diverting to a more suitable alternate.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- January 20, 2004 · about 2:25 am local time
- Place
- Grass Valley, California · Nevada County Airport · map
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- instrument conditions (cloud, fog or low visibility)
- Aircraft
- Cessna 172K · all 172Ks on the register
- Registration
- N99LR · no longer on the register · serial 17259099
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The airplane collided with trees while attempting to land in IFR conditions of near zero visibility in fog. While en route to the destination airport on an IFR clearance, the TRACON controller observed the airplane's transponder discrete code change to 7600 (used by flight crews to indicate a communications failure). The TRACON controller determined that the pilot could hear them, but they could not hear his transmissions. Because of the requirement for full communications in controlled, Class B airspace, they suggested the pilot contact a nearby airport outside of the Class B airspace on the frequency they provided. The pilot contacted the suggested ATCT while 12 miles west of that airport, and the controller could barely hear the pilot's transmissions. The pilot advised the tower to cancel his IFR flight plan and he would proceed visual flight rules (VFR) back to his departure airport without VFR flight following. This was the last communication from the pilot. Witnesses heard the pilot make two approach attempts to land at original departure airport but they could not see the airplane because the airport had become zero visibility and zero ceiling in fog about 20 minutes prior to the airplanes arrival.
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
Pilot
- Certificate: private
- Ratings: single-engine land; instrument: airplane
- Flight time: 1,148 hours in all
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
- Injury: fatal
The aircraft
- Airframe total time: 5,049 hours
- Last inspection: annual inspection, February 1, 2003; 112 hours since
- Maximum gross weight: 2,300 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-320 (piston); 0 hours total
The flight
- Departed from: O17 Grass Valley CA
- Destination: PAO Palo Alto CA
- Flight plan: IFR
Weather at the time
- Light: night
- Visibility: 0.2 statute miles
- Sky: vv at 100 ft
- Temperature: 39°F (4°C), dew point 39°F (4°C)
- Altimeter: 30.09 inHg
- Observation at 2:50 am from KAUN, 16 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the 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.