Aircraft Accident/Incident Report

Poplar Grove, Illinois 61065
Monday, October 6, 1997 13:30 CDT

NTSB Narrative Summary Released at Completion of Accident

The pilot reported that he was cruising at 4,000 feet msl in clear sky conditions with smooth air, then he initiated a descent. He said that while descending through about 3,200 feet msl at 185 mph with a 5 degree nose down attitude and 15 degree left turn, the control yoke started oscillating fore and aft about 1/2 inch. The oscillations increased to about 1 inch fore and aft, and the airplane experienced 3 or 4 'solid jolts.' After about 5 seconds, the pilot reduced power, and the vibrations stopped. He continued to his destination and landed uneventfully. According to the Pilot Operating, the airplane's never exceed airspeed (Vne) was 202 mph. The maximum cruise airspeed (Vno), was 175 mph. Inspection of the airplane revealed that the aft fuselage received extensive damage between fuselage station (FS) 256.9 and the 233.5 bulkhead. The longerons were bent downward with a permanent 2.5 to 3 inch bend. The left and right side fuselage panels below the stabilizers exhibited 45 degree buckling from the bottom of the FS 256.9 bulkhead to forward of the stabilizer cuffs. The bottom fuselage panel forward of the 256.9 bulkhead had popped rivets and torn skin. There were three creases in the right stabilizer. No pre-existing cracks were found on the longerons. The ruddervators were properly balanced.

NTSB Probable Cause Narrative

flutter for an undetermined reason, which resulted in structural damage to the aft fuselage.

Event Information

Type of Event Accident
Event Date 10/6/1997
Event Day of the Week Monday
Time of Event 1330
Event Time Zone Central Daylight Time
Event City POPLAR GROVE
Event State ILLINOIS
Event Country --
Zipcode of the event site 61065
Event Date Year 1997
Event Date Month 10
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
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 Not pertinent
Investigator's weather source Pilot
Time of the weather observation 0
Direction of event from weather observation facility (degrees) 0
Weather Observation Facility ID
Elevation of weather observation facility 0
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation
Lighting Conditions Day
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Clear
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 15
Air Temperature at event time (in degrees celsius) 21
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 300
Variable Wind Indicator Unknown
Wind Speed (knots) 10
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) --
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor --
Injury Total None 2
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 1493
NTSB Notification Source --
NTSB Notification Date Oct 9 1997 12:00AM
NTSB Notification Time 1345
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 8 2000 12:36PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N129B
NTSB Number CHI98FA017
Missing Aircraft Indicator N
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 None
Aircraft Manufacturer's Full Name Beech
Aircraft Model G35
Aircraft Series Identifier G35
Aircraft Serial Number D-4433
Certified Max Gross Weight 2725
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 Jul 8 1997 12:00AM
Airframe hours since last inspection 43
Airframe Hours 5439
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name CHARLES O. PETERSON
Aircraft Owner Street Address 1006 HERON WAY
Aircraft Owner City WOODSTOCK
Aircraft Owner State IL
Aircraft Owner Country
Aircraft Owner Zipcode 60098
Operator is an individual? --
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? No
Certified for Part 133 or 137 Operation Unknown
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 JVL
Departure City JANESVILLE
Departure State WI
Departure Country
Departure Time 1300
Departure Time Zone CDT
Destination Same as Local Flt crash at destination city
Destination Airport Code C77
Destination City
Destination State
Destination Country
Specific Phase of Flight Descent
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:34AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 0
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --