Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Yakima, Washington 98903
Friday, June 21, 2002 13:00 PDT
NTSB Narrative Summary Released at Completion of Accident
The pilot reported that he experienced light to moderate turbulence approximately 10 minutes prior to the accident while cruising at an airspeed of about 150 mph. The pilot initiated a 1,000 foot per minute descent about 15 nautical miles northwest of the airport, and stated that his indicated airspeed was between 170 and 180 mph. During the descent, the pilot stated that the aircraft began to shake violently. The pilot applied equal pressure to the rudder pedals, pulled out the throttle, pitched up the nose to slow down, and the shaking stopped. The pilot continued the descent for landing without further incident. During the inspection of the airframe, wrinkles, creases and compression signatures were found in the skin to both the left and right sides of the empennage from fuselage stations (FS) 233.5 to FS 272 were noted. The airframe skin pulled away from five rivets located on the bottom of the empennage, along the left side, and forward of FS 256.9. The skin from left to right side pulled away from all of the empennage bottom rivets at FS 256.9. The skin pulled away from six of the rivets along the right side, and forward of FS 256.9. The two longitudinal running rivet rows on the bottom had the skin pulled away from seven rivets on the left side and six rivets on the right side. All applicable AD's had been complied with at the time. No AD speed restrictions were in effect for this model aircraft. Normal operating range for this model aircraft is between 66 - 175 mph.
NTSB Probable Cause Narrative
Empennage flutter which resulted in structural damage during descent for landing. Turbulence was a factor.
Event Information
| Type of Event | Accident |
| Event Date | 6/21/2002 |
| Event Day of the Week | Friday |
| Time of Event | 1300 |
| Event Time Zone | Pacific Daylight Time |
| Event City | Yakima |
| Event State | WASHINGTON |
| Event Country | -- |
| Zipcode of the event site | 98903 |
| Event Date Year | 2002 |
| Event Date Month | 6 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 463409N |
| Event Location Longitude | 1203200W |
| 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 | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1256 Pacific Daylight Time |
| Direction of event from weather observation facility (degrees) | 130 |
| Weather Observation Facility ID | YKM |
| Elevation of weather observation facility | 1095 |
| Distance of event from weather observation facility (units?) | 10 |
| Time Zone of the weather observation | PDT |
| 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) | 30 |
| Dew Point at event time (in degress fahrenheit) | 5 |
| Wind Direction (degrees magnetic) | -- |
| Variable Wind Indicator | Variable |
| Wind Speed (knots) | 3 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 29.95 |
| 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 |
| NTSB Docket Number (internal use) | 13523 |
| NTSB Notification Source | Pilot |
| NTSB Notification Date | Jul 1 2002 12:00AM |
| NTSB Notification Time | 1115 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | May 30 2003 9:51AM |
| User who most recently changed record | NTSB\MONR |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Spokane FSDO |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N4647D |
| NTSB Number | SEA02LA116 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | VFR |
| Flight plan Was Activated? | Yes |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Beech |
| Aircraft Model | G35 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | D-4803 |
| Certified Max Gross Weight | 2775 |
| Aircraft Category | Airplane |
| Aircraft Registration Class | U.S. Registered/U.S. Soil |
| Aircraft is a homebuilt? | No |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | 4 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Aug 2 2001 12:00AM |
| Airframe hours since last inspection | 80 |
| Airframe Hours | 5971 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | John I. Cosman |
| Aircraft Owner Street Address | On File |
| Aircraft Owner City | Oak Harbor |
| Aircraft Owner State | WA |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 98277 |
| Operator is an individual? | No |
| Operator Name | -- |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | -- |
| Operator City | -- |
| Operator State | -- |
| Operator Country | -- |
| 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) | Personal |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | KBVS |
| Departure City | Skagit Regional |
| Departure State | WA |
| Departure Country | USA |
| Departure Time | 1130 |
| Departure Time Zone | PDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | KYKM |
| Destination City | Yakima |
| Destination State | WA |
| Destination Country | USA |
| Specific Phase of Flight | Descent |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | Apr 10 2003 10:57AM |
| User who most recently changed record | STAM |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | -- |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |