Amateur-built BD-5T accident near Corvallis, Oregon, June 21, 1998
On June 21, 1998 at about 10:30 pm local time, a amateur-built BD-5T, registered N50TX, was substantially damaged in an accident near Corvallis, Oregon. 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 introduction of a fuel containing an ethanol additive into fuel tanks sloshed/sealed with a compound incompatible with alcohols, resulting in debonding of the compound from the fuel tank walls, leading to partial blockage of an in-line fuel filter, and a total loss of engine power due to fuel starvation. Factors include an inadequate preflight and tall vegetation in the field where the forced landing was attempted.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 21, 1998 · about 10:30 pm local time
- Place
- Corvallis, Oregon · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built BD-5T
- Registration
- N50TX · registry record · serial 629
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
During the assembly of the home-built aircraft, its wet-wing fuel tanks were sloshed with a sealer (Randolph #802) that is not compatible with alcohol fuel additives. During the aircraft's three week engine test run and test flight sequence, Jet-A fuel containing an ethanol fuel additive (Prist) was in its fuel tanks. This resulted in the sloshing compound debonding from the fuel tank walls and partially blocking an in-line fuel filter. Because of this blockage, approximately 25 minutes into the fourth test flight, the aircraft experienced a total loss of power. During the subsequent forced landing, the aircraft nosed over when one of its wings became entangled in tall vegetation. During the investigation it was determined that the owner/builder, the test pilot, representatives of the company that helped mate the engine to the airframe, and the supplier of the engine/propeller/gearbox assembly, all of whom were present for the ground run and test flight sequence on that day, were not aware that an alcohol fuel additive may be present in some Jet-A fuel at the time of purchase.
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: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 775 hours in all; 2 in this make and model; 19 in the last 90 days; 11 in the last 30 days; 690 as pilot in command; 190 on instruments
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: frt
The aircraft
- Airframe total time: 8 hours
- Last inspection: inspection type not recorded, October 1, 1996; 8 hours since
- Landing gear: retractable
- Engine: Quantum APU (turboprop); 0 hours total
The flight
- Departed from: CVO OR at 10:05 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 280° at 9 knots
- Visibility: 20 statute miles
- Sky: clear
- Temperature: 77°F (25°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| 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 N50TX 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.