Wsk Pzl Mielec M-18A accident near Burns, Oregon, July 26, 2004
On July 26, 2004 at about 8:26 pm local time, a Wsk Pzl Mielec M-18A, registered N495WP, was substantially damaged in an accident near Burns, Oregon. 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 improper installation of the throttle linkage clevis to the throttle control arm by unknown maintenance personnel. Contributing factors were the nylon lock nut separating from its' bolt, which permitted the throttle cable to disconnect from the throttle control arm, and the fence post.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 26, 2004 · about 8:26 pm local time
- Place
- Burns, Oregon · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Wsk Pzl Mielec M-18A
- Registration
- N495WP · no longer on the register · serial 1Z0206
- 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 pilot was attempting to climb following a fire retardant drop. When he moved the throttle forward, the engine did not respond. The airplane started loosing altitude, and the pilot performed a forced landing to an open plateau. During the landing, the throttle would not retard all the way. In order to land the airplane, the pilot turned the fuel selector to the off position. During the landing roll, the left wing impacted a fence pole bending ribs and wrinkling the aileron. Post accident examination revealed that the bolt normally connecting the throttle linkage clevis to the throttle arm was missing. The investigating team examined a sister aircraft from the same provider. They found that a nylon lock nut had been installed on the clevis bolt, and it was loose enough to be removed without the aid of any tools. The industry standard, found in FAA Advisory Circular AC43.13-1B, chapter 7, section 4, paragraph 7-64, states that nylon locking nuts should not be used with rotating components or assemblies. It further states that nylon and/or fiber nuts are highly susceptible to wear from repetitive use and from high heat applications.
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: commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 5,047 hours in all; 2,373 in this make and model; 66 in the last 90 days; 33 in the last 30 days; 4,999 as pilot in command
- Last flight review: January 10, 2004
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: sngl
- Injury: no injuries
The aircraft
- Airframe total time: 3,659 hours
- Last inspection: 100-hour inspection, June 22, 2004; 32 hours since
- Maximum gross weight: 11,700 lb
- Seats: 2
- Landing gear: fixed
- Engine: Pezetel ASZ621RM18 (piston); 0 hours total
The flight
- Departed from: BNO Burns OR at 8:00 pm
Weather at the time
- Light: daylight
- Wind: at 4 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 88°F (31°C), dew point 37°F (3°C)
- Altimeter: 30.06 inHg
- Observation at 8:53 pm from BNO, 28 miles away
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.
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.