Amateur-built SEA HAWK accident near Clinton, Iowa, July 25, 1986
On July 25, 1986 at about 10:05 pm local time, a amateur-built SEA HAWK, registered N85CK, was substantially damaged in an accident near Clinton, Iowa. 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 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
- July 25, 1986 · about 10:05 pm local time
- Place
- Clinton, Iowa · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built SEA HAWK
- Registration
- N85CK · no longer on the register · serial 015
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
DURING A TEST FLT OF AN EXPERIMENTAL SEA PLANE, THE PLT RPTD A LOSS OF ENG PWR DURING A TURN IN THE TRAFFIC PATTERN AT CLINTON AIRPORT. THE PLT STATED HE HAD 5 GALLONS OF FUEL ONBOARD AND HAD FLOWN ABOUT 2 TENTHS OF AN HOUR. INSPECTION OF THE FUEL SYSTEM REVEALED THAT DURING TURNS WITH LOW FUEL QUANTITY THE FUEL TANK WOULD BECOME UNPORTED AND THE ENG WOULD QUIT. NO FUEL TANK BAFFLES WERE INSTALLED IN THE TANK TO PREVENT THE FUEL FROM MOVING OUTBOARD FROM THE FUEL LINES. THE PLT STATED THAT THIS PROBLEM WOULD BE CORRECTED WITH THE INSTALLATION OF BAFFLES IN THE TANKS.
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: 172 hours in all; 1 in this make and model; 13 in the last 90 days; 113 as pilot in command
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 1 hours
- Last inspection: annual inspection, July 23, 1986; 1 hours since
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-320 (piston); 0 hours total
The flight
- Departed from: CWI Clinton IA at 10:00 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 030° at 7 knots
- Visibility: 15 statute miles
- Sky: broken clouds at 4,000 ft; not recorded at 4,000 ft
- Temperature: 84°F (29°C), dew point 0°F (-18°C)
- Altimeter: 29.00 inHg
- Observation at 9:45 pm from CDI, 80 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.