Schweizer Aircraft CORP G 164B accident near Biggs, California, May 13, 2014
On May 13, 2014 at about 8:20 pm local time, a 1986 Schweizer Aircraft CORP G 164B, registered N3633C, was substantially damaged in an accident during takeoff near Biggs, California (Jones Ag-Viation Airport). It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). 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 assembler’s improper fabrication of a fuel line (hose) and the subsequent failure to verify that it was not occluded, which resulted in fuel starvation and a total loss of engine power during takeoff.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 13, 2014 · about 8:20 pm local time
- Place
- Biggs, California · Jones Ag-Viation Airport · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Schweizer Aircraft CORP G 164B B, built 1986 · all G 164Bs on the register
- Registration
- N3633C · registry record · serial 776B
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
The commercial pilot departed for his seventh agricultural application flight of the day with a full load of seed on board. The operator reported that, during takeoff, the engine experienced a loss of power and subsequently collided with a berm near the end of the runway. A postaccident examination of the engine and fuel-related accessories revealed no evidence of a mechanical malfunction or failure. The operator had purchased a turbine conversion kit supplemental type certificate about 1 year before the accident. The engine was overhauled and reinstalled on the airplane, which was subsequently flown about 170 hours without incident. Postaccident examination of the engine revealed that, during the conversion, maintenance personnel installed a fuel line (hose) from the firewall to the gascolator that was different from that shown in the engineering drawings. The installed hose was shorter and had a 90-degree fitting on one side and a straight fitting on the other rather than straight fittings on both ends. The hose was occluded by a piece of the hose's inner lining. Compressed air was directed through one end of the hose and a black piece of material ejected out the opposite side. An internal examination of the hose assembly revealed that there were flaps of loose hose where the end of the 90-degree fitting rested against the interhose walls. The flap material and the ejected piece of material both matched the material of the interhose; these materials likely completely blocked the hose, which resulted in fuel starvation to the engine. A representative from the hose manufacturer stated that, when the hose assembler starts and stops the installation of the nipple into the hose, significant heat can build up from the induced friction caused by the continuous starting and stopping motion; this can break down the binding that holds the inner tube to the outer layers of the hose and may result in the nipple digging into the inside diameter of the hose liner. In extreme cases, this can result in the inner liner twisting and lead to a complete blockage of the hose, which is likely what occurred to the accident hose. The representative further stated that, after the hose assembly process, the assembler should route a specific-sized ball through the hose assembly to ensure there is no blockage or obstruction. However, the manufacturer's hose assembly instructions did not provide detailed instructions on the assembly process or recommend how to verify that the hose was not occluded during assembly.
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 (total) during takeoff defining event
The NTSB's findings
- cause Aircraft › Aircraft systems › Fuel system › (general) › Incorrect service/maintenance
- cause Aircraft › Aircraft systems › Fuel system › (general) › Inadequate inspection
- cause Personnel issues › Task performance › Inspection › Post maintenance inspection › Maintenance personnel
- cause Aircraft › Fluids/misc hardware › Fluids › Fuel › Fluid level
- cause Aircraft › Aircraft systems › Fuel system › (general) › Damaged/degraded
- Environmental issues › Physical environment › Terrain › (general) › Contributed to outcome
- Organizational issues › Development › Design › Policy/procedure development › Manufacturer
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land
- Flight time: 18,300 hours in all; 2,000 in this make and model
- Last flight review: April 12, 2013
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: ctr
- Injury: no injuries
The aircraft
- Airframe total time: 10,556 hours
- Last inspection: 100-hour inspection, April 3, 2014; 63 hours since
- Seats: 1
- Landing gear: fixed
- Engine: Pratt And Whitney PT6A-34 (turboprop); 9,545 hours total
The flight
- Departed from: CL23 Biggs CA at 8:10 pm
- Destination: CL23 Biggs CA
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: at 5 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 90°F (32°C), dew point 32°F (0°C)
- Altimeter: 30.13 inHg
- Observation at 12:53 pm from OVE, 4 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 N3633C 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.