Cessna 172P and Cessna 172P mid-air collision near Seattle, Washington, April 5, 1986
On April 5, 1986 at about 10:30 pm local time, 2 aircraft, Cessna 172P (N99034) and Cessna 172P (N65783), were involved in a mid-air collision near Seattle, Washington (Kenmore Air Harbor airport). 4 people were 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 November 2, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 5, 1986 · about 10:30 pm local time · cases in 1986
- Place
- Seattle, Washington · Kenmore Air Harbor · cases near this airport · map
- Type
- Accident · mid-air collision
- Injuries
- 4 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft 1
- Cessna 172P · all 172Ps on the register
- Registration
- N99034 · no longer on the register · serial 17276394
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
- Aircraft 2
- Cessna 172P · all 172Ps on the register
- Registration
- N65783 · registry record · serial 17275883
- Damage
- Destroyed
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative for the Cessna 172P final · quoted from the NTSB record
N99034 DEPARTED KENMORE AIR HARBOR ON A SHORT LOCAL SOLO FLIGHT. WITNESSES REPORTED OBSERVING THE AIRCRAFT TAKEOFF AND INITIATE A CLIMB TO THE SOUTH. N65783 WAS RETURNING FROM A RECURRENCY CHECK FLIGHT AND WAS APPROACHING FROM A SOUTHERLY DIRECTION IN A CLIMB HAVING JUST COMPLETED A TOUCH AND GO LANDING. BOTH AIRCRAFT WERE APPROXIMATELY 200 FEET MSL AT THE TIME OF THE COLLISION. THE RIGHT WING FROM N99034 SEPARATED IN AN AFTWARDS FASHION UPON IMPACT WITH THE RIGHT FLOAT OF N65783. A 49 INCH SECTION OF OUTBOARD RIGHT WING FROM N65783 SEPARATED DURING ITS PENETRATION INTO THE COCKPIT OF N99034. NUMEROUS BOATS WERE OBSERVED ON THE LAKE SURFACE AND CLEAR SUNNY METEOROLOGICAL CONDITIONS PREVAILED.
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 NTSB's narrative for the Cessna 172P final · quoted from the NTSB record
N99034 DEPARTED KENMORE AIR HARBOR ON A SHORT LOCAL SOLO FLIGHT. WITNESSES REPORTED OBSERVING THE AIRCRAFT TAKEOFF AND INITIATE A CLIMB TO THE SOUTH. N65783 WAS RETURNING FROM A RECURRENCY CHECK FLIGHT AND WAS APPROACHING FROM A SOUTHERLY DIRECTION IN A CLIMB HAVING JUST COMPLETED A TOUCH AND GO LANDING. BOTH AIRCRAFT WERE APPROXIMATELY 200 FEET MSL AT THE TIME OF THE COLLISION. THE RIGHT WING FROM N99034 SEPARATED IN AN AFTWARDS FASHION UPON IMPACT WITH THE RIGHT FLOAT OF N65783. A 49 INCH SECTION OF OUTBOARD RIGHT WING FROM N65783 SEPARATED DURING ITS PENETRATION INTO THE COCKPIT OF N99034. NUMEROUS BOATS WERE OBSERVED ON THE LAKE SURFACE AND CLEAR SUNNY METEOROLOGICAL CONDITIONS PREVAILED.
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 for the Cessna 172P from the NTSB's investigation tables, in plain English
Pilot
- Certificate: private
- Ratings: single-engine land; single-engine sea
- Flight time: 98 hours in all; 25 in this make and model; 7 in the last 90 days; 48 as pilot in command
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 554 hours
- Last inspection: annual inspection, March 4, 1986; 66 hours since
- Maximum gross weight: 2,400 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-320-D2J (piston); 0 hours total
- Operator: Kenmore Air Harbor
The flight
- Departed from: S60 Seattle WA at 10:25 pm
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 270° at 8 knots
- Visibility: 40 statute miles
- Sky: scat at 2,000 ft
- Temperature: 55°F (13°C), dew point 36°F (2°C)
- Altimeter: 30.00 inHg
- Observation at 10:45 pm from PAE, 10 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 |
The factual record for the Cessna 172P from the NTSB's investigation tables, in plain English
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: single-engine land; single-engine sea; instructor: airplane single-engine; instrument: airplane
- Flight time: 1,590 hours in all; 804 in this make and model; 1,430 as pilot in command
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 1,734 hours
- Last inspection: 100-hour inspection, March 31, 1986; 15 hours since
- Maximum gross weight: 2,400 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-320-D2J (piston); 0 hours total
- Operator: Kenmore Air Harbor
The flight
- Departed from: S60 Seattle WA at 10:00 pm
- Runway 0
- A second pilot was aboard
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 | |||
| 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.
Connections how this case links to the rest of the register
- N99034: not on the register today · the record of its deregistration
- Cessna 172 Skyhawk 20,692 registered today · the model family and its accident history
- Cessna 72,677 aircraft on the register
- N65783 on the register today · the tail number may have moved to another aircraft since
- Cessna 172 Skyhawk 20,692 registered today · the model family and its accident history
- Cessna 72,677 aircraft on the register
- Engine: Lycoming O-320-D2J 96 aircraft carry this series today · as the NTSB recorded it
- Engine: Lycoming O-320-D2J 96 aircraft carry this series today · as the NTSB recorded it
- Kenmore Air Harbor Seaplane Base · nearest airport
- Accidents and incidents in Washington 2,713 since 1982 · 361 in the last ten years
- Washington 10,663 aircraft registered
The whole map of how records connect · these connections as data: /graph/accident/SEA86FA092.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.