Aircraft Accident/Incident Report

Green Lake, Wisconsin 54941
Sunday, July 25, 2010 12:30 CDT

NTSB Narrative Summary Released at Completion of Accident

The pilot reported that, while on approach to the destination airport, the engine experienced a total loss of power. He selected an uphill-sloped soybean field to make a forced landing and retracted the landing gear. The airplane slid 260 feet before coming to a stop. The airplane sustained firewall damage during the landing sequence. The postaccident investigation revealed several anomalies with the engine that were not in accordance with engine manufacturer's recommended maintenance practices. The No. 2 bearing was dislodged/separated and remnants of it were most likely the metallic debris found in the oil sump and oil filter. The cylinder thru-bolts were found to be tight; however, 19 of the 36 cylinder deck stud nuts were loose. A crack was observed between the No. 4 main bearing saddle on the left half of the crankcase, which extended through the No. 5 main bearing saddle. The pilot reported that the airplane had undergone a top overhaul about 18 flight hours prior to the accident. At the conclusion of the examination, the exact cause of the engine failure could not be definitively identified.

NTSB Probable Cause Narrative

A total loss of engine power during descent due to the overhaul facility’s inadequate maintenance.

Event Information

Type of Event Accident
Event Date 7/25/2010
Event Day of the Week Sunday
Time of Event 1230
Event Time Zone Central Daylight Time
Event City Green Lake
Event State WISCONSIN
Event Country --
Zipcode of the event site 54941
Event Date Year 2010
Event Date Month 7
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 434304N
Event Location Longitude 0890312W
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 Unknown
Time of the weather observation 1253 Central Daylight Time
Direction of event from weather observation facility (degrees) 58
Weather Observation Facility ID OSH
Elevation of weather observation facility 808
Distance of event from weather observation facility (units?) 31
Time Zone of the weather observation CDT
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) 26
Dew Point at event time (in degress fahrenheit) 13
Wind Direction (degrees magnetic) 110
Variable Wind Indicator Wind direction could be determined
Wind Speed (knots) 6
Wind Velocity Indicator --
Wind Gust Indicator Not Gusting
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) 30.11
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) 27921
NTSB Notification Source Green Lake County Sheriff
NTSB Notification Date --
NTSB Notification Time --
Fiche Number and/or location -used to find docket information --
Date of most recent change to record Nov 2 2010 12:16PM
User who most recently changed record bowl
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N5443D
NTSB Number CEN10LA433
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 BEECH
Aircraft Model H35
Aircraft Series Identifier --
Aircraft Serial Number D-4991
Certified Max Gross Weight 2900
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 4
Number of Engines 1
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Jul 20 2010 12:00AM
Airframe hours since last inspection 19
Airframe Hours 4126
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name N407ML LLC
Aircraft Owner Street Address --
Aircraft Owner City Wilmington
Aircraft Owner State DE
Aircraft Owner Country USA
Aircraft Owner Zipcode 19810
Operator is an individual? No
Operator Name Michael A. Lella
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address --
Operator City Groveland
Operator State CA
Operator Country USA
Operator Zip code 95321
Operator Code --
Owner has at least one certificate None
Other Operator of large aircraft? No
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 PDC
Departure City Prairie Du Chie
Departure State WI
Departure Country USA
Departure Time 1145
Departure Time Zone CDT
Destination Same as Local Flt --
Destination Airport Code OSH
Destination City Oshkosh
Destination State WI
Destination Country USA
Specific Phase of Flight --
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Oct 26 2010 5:58PM
User who most recently changed record sulp
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 --