Thorp T 18 accident near Independence, Oregon, November 6, 2015
On November 6, 2015 at about 11:30 pm local time, a 1968 Thorp T 18, an amateur-built aircraft,, registered N1488, was substantially damaged in an accident during initial climb near Independence, Oregon (Independence State airport). 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
A separation of the canopy mechanism during flight, which resulted in the pilot’s precautionary landing and the airplane’s subsequent collision with a fence post.
Source: NTSB aviation accident database, copy made November 2, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 6, 2015 · about 11:30 pm local time · cases in 2015
- Place
- Independence, Oregon · Independence State · cases near this airport · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Thorp T 18 UNDESIGNAT, built 1968, amateur-built · all T 18s on the register
- Registration
- N1488 · registry record · serial 303
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot departed on a local flight; during initial climb, the canopy partially disconnected from the airplane and the airplane vibrated violently. The pilot made a precautionary landing in a field, and the right wing impacted a fence post. Postaccident examination revealed that the mechanism that allowed the canopy to move fore and aft and retained the aft portion of the canopy during flight separated at a weld, which resulted in airflow into the cockpit. The components were not made available for metallurgical examination and the failure mode could not be determined; however, it is possible that the separation was due to repeated loading on the canopy over time. According to the pilot and a representative of the airplane type club, the canopy design was unique to the accident airplane, and was likely the only one of its kind.
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
- Sys/Comp malf/fail (non-power) during initial climb defining event
- Collision with terrain or object (not controlled flight into terrain) during landing (landing roll)
The NTSB's findings
- cause Aircraft › Aircraft structures › Doors › Passenger/crew doors › Failure other cases naming the airframe structure
- Environmental issues › Physical environment › Object/animal/substance › Fence/fence post › Contributed to outcome
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 618 hours in all; 618 in this make and model; 18 in the last 90 days; 8 in the last 30 days
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 1,358 hours
- Last inspection: condition inspection, March 1, 2015; 19 hours since
- Maximum gross weight: 1,540 lb
- Seats: 2
- Landing gear: fixed
- Engine: Textron Lycoming O-320-B2A (piston); 1,358 hours total
The flight
- Departed from: Independence OR
- Destination: Independence OR
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 340° at 6 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 135°F (57°C), dew point 115°F (46°C)
- Altimeter: 30.31 inHg
- Observation at 7:56 pm from KSLE, 9 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
5 documents, released by the NTSB on September 22, 2016. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 9 pages | View Download |
| 2 | Pilot Record of Conversation | PDF, 1 page | View Download |
| 3 | FAA Record of Conversation | PDF, 1 page | View Download |
| 4 | Thorp T-18 Group Record of Conversation | PDF, 1 page | View Download |
| 5 | WPR16LA023 Photos | PDF, 3 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Connections how this case links to the rest of the register
- N1488 on the register today · the tail number may have moved to another aircraft since
- Thorp T-18 27 registered today · the model family and its accident history
- Thorp 27 aircraft on the register
- Engine: Textron Lycoming O-320-B2A 11 aircraft carry this series today · as the NTSB recorded it
- Independence State Airport · nearest airport
- Accidents and incidents in Oregon 1,864 since 1982 · 279 in the last ten years
- Oregon 7,008 aircraft registered
The whole map of how records connect · these connections as data: /graph/accident/WPR16LA023.json.
The bigger picture in Aviation Analytics: accidents over time since 1982, by model, by phase of flight and conditions, by place and on the map.
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 does not name anyone involved, its policy at this time. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.