Aircraft Accident/Incident Report

Seattle, Washington 98122
Tuesady, August 14, 2007 14:00 PDT

NTSB Narrative Summary Released at Completion of Accident

During the floatplane instructional flight, the private pilot decided to make a practice landing and takeoff on a large lake. Although the landing on the calm water was uneventful, during the takeoff run, just before liftoff, the aircraft encountered the wake of a large boat. As the aircraft crossed the crest of the first wave of the wake, it became momentarily airborne, and then it impacted the advancing forward face of the second wave. At the moment of impact, four of the float attach fittings failed. The pilot therefore immediately aborted the takeoff, but the right wing impacted the surface of the water before the aircraft came to a stop. Neither the private pilot nor the instructor pilot that was supervising him had seen the large swell approaching during the landing, and during the takeoff run, neither of them noticed it until a few seconds prior to the time the aircraft impacted it.

NTSB Probable Cause Narrative

The private pilot's failure to see the approaching large wake swell, both during his landing and the subsequent takeoff, and the failure of the instructor pilot to insure that the private pilot's visual lookout was effective enough to detect the oncoming wake. Factors include a wake generated by a large boat.

Event Information

Type of Event Accident
Event Date 8/14/2007
Event Day of the Week Tuesday
Time of Event 1400
Event Time Zone Pacific Daylight Time
Event City Seattle
Event State WASHINGTON
Event Country --
Zipcode of the event site 98122
Event Date Year 2007
Event Date Month 8
MidAir Collision Indicator No
On Ground Collision occurred ? Yes
Event Location Latitude 473700N
Event Location Longitude 1221600W
Event Location Airport --
Event Location Nearest Airport ID --
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation --
Weather Briefing Completeness --
Investigator's weather source Pilot
Time of the weather observation
Direction of event from weather observation facility (degrees) --
Weather Observation Facility ID --
Elevation of weather observation facility --
Distance of event from weather observation facility (units?) --
Time Zone of the weather observation --
Lighting Conditions Day
Lowest Ceiling Height --
Lowest Non-Ceiling Height --
Sky/Lowest/Cloud Conditions Clear
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) 22
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 10
Variable Wind Indicator Wind direction could be determined
Wind Speed (knots) 5
Wind Velocity Indicator --
Wind Gust Indicator Not Gusting
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) --
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
Injury Total Fatal --
Injury Total Minor --
Injury Total None 2
Injury Total Serious --
Injury Total All --
Investigating Agency --
NTSB Docket Number (internal use) 22545
NTSB Notification Source FAA Operations Center
NTSB Notification Date --
NTSB Notification Time --
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Nov 29 2007 8:02AM
User who most recently changed record NTSB\johb
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N7657X
NTSB Number SEA07CA235
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion --
Aircraft Manufacturer's Full Name CESSNA
Aircraft Model 172B
Aircraft Series Identifier --
Aircraft Serial Number 17248157
Certified Max Gross Weight --
Aircraft Category Airplane
Aircraft Registration Class --
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft --
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Jun 1 2007 12:00AM
Airframe hours since last inspection --
Airframe Hours 2954
ELT Installed Unknown
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name Stephen A. Tibbitts
Aircraft Owner Street Address --
Aircraft Owner City --
Aircraft Owner State --
Aircraft Owner Country --
Aircraft Owner Zipcode --
Operator is an individual? No
Operator Name --
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address --
Operator City Spanaway
Operator State WA
Operator Country USA
Operator Zip code --
Operator Code --
Owner has at least one certificate None
Other Operator of large aircraft? --
Certified for Part 133 or 137 Operation --
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not --
Indicates Domestic or International Flight --
Operator carrying Pax/Cargo/Mail --
Type of Flying (Per_Bus / Primary) Instructional
Second Pilot on Board Yes
Departure Point Same as Event Yes
Departure Airport Code --
Departure City Seattle
Departure State WA
Departure Country USA
Departure Time --
Departure Time Zone --
Destination Same as Local Flt --
Destination Airport Code --
Destination City Spanaway
Destination State WA
Destination Country USA
Specific Phase of Flight --
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Apr 6 2009 1:56PM
User who most recently changed record johb
Since inspection or accident Last Inspection
Event Location Runway Number and Location N/A
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --