Piper PA-18-150 accident near Sunnyside, Washington, April 7, 1985
On April 7, 1985 at about 7:14 pm local time, a Piper PA-18-150, registered N4379Z, was destroyed in an accident near Sunnyside, Washington. It was a personal flight under general aviation rules (Part 91). 1 person was killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 7, 1985 · about 7:14 pm local time
- Place
- Sunnyside, Washington · map
- Type
- Accident
- Injuries
- 1 person was killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Piper PA-18-150 · all PA-18-150s on the register
- Registration
- N4379Z · registry record · serial 18-8701
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE ACFT CRASHED AFTER COLLIDING WITH ELECTRICAL POWER LINES NEAR AN OPEN FIELD. INITIAL IMPACT WITH THE POWER LINES OCCURRED WHERE THE WIRES WERE ROUTED OVER A DRAW BETWEEN 2 RIDGES. THE ACFT CAME TO REST INVERTED BETWEEN THE POWER LINES & THE OPEN FIELD. THE ACFT WAS RELATIVELY INTACT WITH EXTENSIVE GROUND IMPACT DAMAGE TO THE LEFT WING & COMPRESSION & TWISTING TO THE REAR FUSELAGE. THERE WAS HEAVY SCRAPE MARKS ON THE LEFT MAIN GEAR. THE PROP SHOWED NO ROTATIONAL MARKS OR DAMAGE. THE LEFT FUEL CAP WAS OFF & SOME FUEL WAS REMAINING IN THE REAR CORNER. THE RIGHT FUEL CAP WAS IN PLACE. THE CARB HEAT CONTROL WAS WEDGED IN THE ON/HOT POSITION. THE CONNECTING WIRES TO THE STARTER SWITCH WERE FOUND CORRODED AT THE ATTACH SCREWS, THEY WERE PARTLY SEPARATED & THE CASE WAS BROKEN. NO PREIMPACT PART FAILURE OR MALFUNCTION WAS VERIFIED.
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: single-engine land
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: ctr
The aircraft
- Airframe total time: 2,016 hours
- Last inspection: annual inspection, December 10, 1984; 78 hours since
- Maximum gross weight: 1,750 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-320 (piston); 0 hours total
The flight
- Departed from: S40 Prosser WA at 6:30 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 300° at 11 knots
- Visibility: 35 statute miles
- Sky: overcast at 10,000 ft; scat at 6,500 ft
- Temperature: 64°F (18°C), dew point 21°F (-6°C)
- Altimeter: 30.00 inHg
- Observation at 7:51 pm from YKN, 30 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.
Other NTSB records under N4379Z 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.