Cessna 172 accident near Glendora, California, January 31, 2011
On January 31, 2011 at about 11:25 pm local time, a Cessna 172, registered N6922A, was substantially damaged in an accident during maneuvering near Glendora, California. It was an instructional flight under general aviation rules (Part 91). 1 person was seriously injured and 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The flight crew's failure to maintain adequate terrain clearance while maneuvering in downdraft conditions over mountains.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- January 31, 2011 · about 11:25 pm local time
- Place
- Glendora, California · map
- Type
- Accident
- Injuries
- 1 person was seriously injured and 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 172 · all 172s on the register
- Registration
- N6922A · no longer on the register · serial 29022
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The flight instructor reported that he and the commercially certificated student flew to mountainous terrain to practice using orographic lift. The flight instructor stated that the lift they were flying in began to dissipate so he took the flight controls and added full power to depart the area. Suddenly, they encountered a strong downdraft and moments later they impacted the terrain. It is likely that the airplane was not at a sufficient altitude for the pilot to recover from the downdraft encounter and clear the terrain. The flight instructor told local authorities at the time of his rescue that there were no problems with the airplane. A postaccident examination revealed no evidence of any preimpact mechanical anomalies with the airframe or engine 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
- Collision with terrain or object (not controlled flight into terrain) during maneuvering defining event
The NTSB's findings
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Altitude › Not attained/maintained
- Environmental issues › Physical environment › Terrain › Mountainous/hilly terrain › Not specified
- Environmental issues › Conditions/weather/phenomena › Wind › Downdraft › Contributed to outcome
- cause Personnel issues › Action/decision › Info processing/decision › Decision making/judgment › Flight crew
Flight instructor
- Certificate: flight instructor, commercial pilot
- Ratings: single-engine land; instructor: airplane single-engine; instrument: airplane
- Flight time: 1,800 hours in all
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: left
- Injury: serious injuries
Dual student
- Certificate: commercial pilot
- Ratings: single-engine land
- Flight time: 300 hours in all
- Last flight review: November 22, 2010
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: rgt
- Injury: minor injuries
The aircraft
- Airframe total time: 2,796 hours
- Last inspection: 100-hour inspection, January 30, 2011
- Maximum gross weight: 2,200 lb
- Seats: 4
- Landing gear: fixed
- Engine: Continental O-300A (piston); 0 hours total
The flight
- Departed from: POC La Verne CA at 10:32 pm
- Destination: POC La Verne CA
- Flight plan: none
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 260° at 8 knots
- Visibility: 10 statute miles
- Sky: a few clouds at 4,000 ft
- Temperature: 63°F (17°C), dew point 45°F (7°C)
- Altimeter: 30.09 inHg
- Observation at 11:53 pm from CNO, 16 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | 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.