Amateur-built SUPER GLASAIR TT accident near Madera, California, June 8, 2014
On June 8, 2014 at about 11:30 pm local time, a 2013 amateur-built SUPER GLASAIR TT, registered N400MC, was substantially damaged in an accident during enroute (cruise) near Madera, California. 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 loosening of a B-nut in the fuel system which resulted in a rapid, undetected fuel leak and subsequent fuel exhaustion.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 8, 2014 · about 11:30 pm local time
- Place
- Madera, California · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built SUPER GLASAIR TT NO SERIES, built 2013
- Registration
- N400MC · no longer on the register · serial 101
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The commercial pilot, who was also the builder of the experimental airplane, departed with full fuel for the planned 2.5-hour cross-country flight. The airplane was equipped with two independent means of determining fuel quantity: a capacitance-based fuel quantity indication system that provided a direct measurement of the fuel quantity and a fuel totalizer that provided a calculated value using a pilot-entered initial fuel quantity and a sensed fuel flow rate. The pilot reported that both quantity indication systems were reliable and normally registered similar values. While in cruise, after he had been airborne for about 1.5 hours, the pilot noted that each system indicated a remaining fuel quantity of about 38 gallons, which was ample fuel for the completion of the trip. A few minutes later, the engine lost all power. The pilot noticed that the totalizer indicated about 37 gallons remaining but that the capacitance system indicated minimal or no fuel remaining. The pilot determined that he would be unable to reach the nearest airport and set up for a forced landing on a road. Due to motor vehicle traffic, the pilot landed on the side of the road, and the airplane sustained substantial damage due to impact with a bordering fence and vegetation. Postaccident examination of the airplane revealed that a B-nut in the fuel system had backed off. The loose B-nut was just downstream of a fuel pump, which allowed fuel to leak overboard at a location that could not be seen from the cockpit by the pilot. Because of the leak location, once the leak began, the totalizer-indicated fuel quantity became erroneous, but the capacitance-based system quantity remained accurate. The evidence indicated that once the leak began, the fuel was depleted rapidly. The pilot reported that when he was building the airplane, he installed the B-nut, torqued it to prevent loosening, and marked it with a torque stripe. The airplane had been flown about 56 hours since the B-nut was installed. Although maintenance activity conducted to repair an oil leak near the B-nut could have resulted in inadvertent and undetected loosening of the B-nut, the investigation was unable to determine a specific cause for the loosening of the B-nut.
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
- Powerplant sys/comp malf/fail during enroute (cruise)
- Fuel exhaustion during enroute (cruise) defining event
- Collision with terrain or object (not controlled flight into terrain) during landing (landing roll)
The NTSB's findings
- cause Aircraft › Aircraft systems › Fuel system › Fuel distribution › Failure
- cause Aircraft › Fluids/misc hardware › Fluids › Fuel › Fluid level
Pilot
- Certificate: airline transport pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 17,100 hours in all; 795 in this make and model; 310 in the last 90 days; 85 in the last 30 days; 13,580 as pilot in command
- Last flight review: November 23, 2013
- Medical certificate: Class 1 (with waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 56 hours
- Last inspection: condition inspection, March 6, 2014
- Maximum gross weight: 2,500 lb
- Seats: 2
- Landing gear: retractable
- Engine: Lycoming TIO-580 (piston); 145 hours total
The flight
- Departed from: CRQ Carlsbad CA
- Destination: RTS Reno NV
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 290° at 7 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 100°F (38°C), dew point 45°F (7°C)
- Altimeter: 29.69 inHg
- Observation at 11:53 pm from MAE, 10 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 N400MC 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.