Piper PA-18 accident near Skwentna, Alaska, August 14, 1996
On August 14, 1996, a Piper PA-18, registered N7797B, was substantially damaged in an accident near Skwentna, Alaska. It was a personal flight under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
An engine failure due to an eroded engine piston. Factors in the accident were unsuitable terrain for a forced landing and improperly timed magnetos.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 14, 1996
- Place
- Skwentna, Alaska · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Piper PA-18 · all PA-18s on the register
- Registration
- N7797B · registry record · serial 18-4449
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The certificated private pilot and the sole passenger departed a remote lake in a float equipped airplane. About 3 minutes after departure, the engine began to run rough and then quit. The pilot turned back toward the lake, but was unable to glide to the lake and landed on the shoreline. Postaccident inspection of the engine revealed no compression in the number 4 cylinder. The top piston compression ring was frozen in its slot. The outer and upper edge of the top of the piston was eroded and scored. Tiny particles of the piston material were attached to the spark plugs. One magneto was timed 4 degrees before the recommended setting of 25 degrees.
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: private
- Ratings: single-engine land; single-engine sea
- Flight time: 430 hours in all; 285 in this make and model; 81 in the last 90 days; 33 in the last 30 days; 430 as pilot in command
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: frt
The aircraft
- Airframe total time: 516 hours
- Last inspection: annual inspection, February 6, 1996; 212 hours since
- Maximum gross weight: 1,750 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-320-A2B (piston); 0 hours total
The flight
- Destination: Beluga AK
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 180° at 5 knots
- Visibility: 30 statute miles
- Sky: clear
- Temperature: 61°F (16°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 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 N7797B 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.