Cessna 172 incident near Seattle, Washington, November 16, 2006
On November 16, 2006 at about 10:20 pm local time, a Cessna 172, registered N9522S, was involved in an incident near Seattle, Washington (Boeing Field/King County Int.). It was an instructional 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
The instructor pilot's improper in-flight decision not to take evasive action as a heavy aircraft passed by while on an upwind parallel approach path to an adjacent runway, leading to a wake vortices encounter. Factors include a nearly direct crosswind blowing from the heavy aircraft toward the incident aircraft.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 16, 2006 · about 10:20 pm local time
- Place
- Seattle, Washington · Boeing Field/King County Int. · map
- Type
- Incident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 172 · all 172s on the register
- Registration
- N9522S · registry record · serial 17280432
- Damage
- Not recorded
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
While on a VFR straight-in approach in a Cessna 172, the flight instructor and her student were advised by the tower that a heavy Boeing 747, which was behind and above the 172, was executing a visual approach to an upwind parallel runway. Although the 747 crew did not have the 172 in sight, the flight instructor in the 172 spotted the 747 soon after being advised of its presence by the tower. The instructor maintained visual contact with the descending 747, and as the 747 neared a point where it would pass the 172, the instructor elected to continue the VFR approach at about the same altitude and on the same course as before. The instructor then watched as the still-descending 747 passed upwind of the 172 at a slightly higher altitude than the 172 was at. When the 747 reached a point about one-quarter mile in front of the 172, the 172 encountered the wake vortices from the 747, and immediately departed controlled flight. Recovery was completed about 150 feet above the terrain. At the time that the 747 passed the 172, the instructor was aware that there was a nine knot wind blowing almost directly across the parallel flight paths of the two aircraft, and although the instructor had requested a low approach at the runway, the instructor did not take evasive action when the 747 passed the 172 while on approach.
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
Flight instructor
- Certificate: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instrument: airplane
- Flight time: 629 hours in all; 59 in this make and model; 70 in the last 90 days; 17 in the last 30 days; 542 as pilot in command; 172 on instruments
- Last flight review: May 1, 2006
- Medical certificate: Class 1 (without waivers/limitations)
- Seat: rgt
- Injury: no injuries
Dual student
- Certificate: student
- Flight time: 10 hours in all; 10 in this make and model; 6 in the last 30 days
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 4,077 hours
- Last inspection: 100-hour inspection, October 1, 2006
- Maximum gross weight: 2,550 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming IO-360-L2A (piston); 0 hours total
The flight
- Departed from: KBFI Seattle WA at 9:20 pm
- Destination: KBFI
- Flight plan: none
- Runway 13L, 3,709 ft by 100 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 210° at 9 knots
- Visibility: 10 statute miles
- Sky: scat at 3,000 ft
- Temperature: 52°F (11°C), dew point 34°F (1°C)
- Altimeter: 30.01 inHg
- Observation at 9:53 pm from KBFI, 3 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
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.