Aeronca 7AC accident near Novato, California, February 10, 2011
On February 10, 2011 at about 9:52 pm local time, a Aeronca 7AC, registered N2659E, was substantially damaged in an accident during enroute near Novato, California (Gnoss Field). 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 use of a non-vented fuel cap, which resulted in a total loss of engine power due to fuel starvation.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 10, 2011 · about 9:52 pm local time
- Place
- Novato, California · Gnoss Field · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Aeronca 7AC · all 7ACs on the register
- Registration
- N2659E · no longer on the register · serial 7AC-6241
- 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 while in cruise flight, the engine suddenly started running rough and the engine rpms rapidly decreased from 2,100 to 1,900. The pilot immediately applied full carburetor heat, but the engine continued running rough so he headed toward the nearest airport. While on the base leg of the traffic pattern, the engine lost all power. The airplane subsequently touched down short of the runway and collided with a fence. Postaccident examination of the wreckage found that the left auxiliary fuel tank was empty and the right auxiliary tank was about one-third full. The auxiliary tank fuel selector under the instrument panel was found in the off position. The main fuel tank, which was configured to feed the engine, was full and the fuel indicator also indicated full. Further examination of the engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The pilot reported that the main fuel tank fuel cap was misplaced when the airplane was refueled. The pilot then borrowed a fuel cap from a local mechanic and installed it on the main tank filler port. An examination of the airplane revealed that the borrowed fuel cap was a non-vented type; because there was no other vent for the main tank, the only vent would be through a vented cap. As fuel was used from the main tank, the lack of a vented cap caused a vacuum within the main tank that eventually reduced the fuel flow, starving the engine. Had an auxiliary tank been selected, adequate venting would have occurred because both auxiliary tanks had vented fuel caps.
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
- Loss of engine power (partial) during enroute defining event
- Loss of engine power (total) during approach (VFR pattern base)
- Off-field or emergency landing during landing (flare/touchdown)
- Collision with terrain or object (not controlled flight into terrain) during landing (landing roll)
The NTSB's findings
- Environmental issues › Physical environment › Object/animal/substance › Fence/fence post › Contributed to outcome
- cause Aircraft › Aircraft systems › Fuel system › (general) › Incorrect service/maintenance
- cause Personnel issues › Task performance › Maintenance › Replacement › Pilot
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 1,876 hours in all; 1,200 in this make and model; 5 in the last 90 days; 3 in the last 30 days; 1,650 as pilot in command; 0 on instruments
- Last flight review: January 6, 2011
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: frt
- Injury: no injuries
The aircraft
- Airframe total time: 4,916 hours
- Last inspection: annual inspection, November 19, 2010; 3 hours since
- Seats: 2
- Landing gear: fixed
- Engine: Cont Motor O-200A (piston); 0 hours total
The flight
- Departed from: DVO Novato CA at 8:30 pm
- Destination: DVO Novato CA
- Flight plan: none
- Runway 13, 3,300 ft by 75 ft
Weather at the time
- Light: daylight
- Wind: from 120° at 4 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 61°F (16°C), dew point 30°F (-1°C)
- Altimeter: 30.17 inHg
- Observation at 9:50 pm from DVO, 1 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 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.
Other NTSB records under N2659E the same tail number, which may have belonged to a different aircraft at the time
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.