Individually Owned: 150,657
Corporate Owned: 137,281
Tanner Airstrip Airport
Aircraft Accident/Incident Report
Roberts, Idaho 83444
Saturday, September 18, 2010 9:10 MDT
NTSB Narrative Summary Released at Completion of Accident
The pilot, who was also the airplane's owner, reported that the engine of the experimental amateur-built airplane experienced a partial loss of power while turning onto the crosswind leg of the traffic pattern after the initial takeoff climb. The pilot initiated a return to the runway, during which time the engine lost all power. The pilot unsuccessfully attempted to restart the engine and subsequently performed an off-airport landing. The airplane's right main landing gear collapsed during the landing roll, resulting in substantial damage to the airframe. Examination of the engine revealed that the left carburetor was detached from the engine inlet manifold. The impact trajectory, coupled with a lack of witness marks indicating the carburetor had struck any part of the airplane, make it most likely that the carburetor detached in flight. The owner/pilot reported that he had experienced excessive engine vibration and "kickback" during prior startups. He had considered a number of remedial measures to rectify the problem, but had not performed any of these measures prior to the accident flight. He additionally reported that he could have reduced the likelihood of the carburetor separating by more thoroughly examining the tension of its mounting hardware.
NTSB Probable Cause Narrative
A loss of engine power due to the detachment of the left carburetor from the engine inlet manifold. Contributing to the accident was the pilot's failure to address a known engine vibration.
Event Information
| Type of Event | Accident |
| Event Date | 9/18/2010 |
| Event Day of the Week | Saturday |
| Time of Event | 910 |
| Event Time Zone | Mountain Daylight Time |
| Event City | Roberts |
| Event State | IDAHO |
| Event Country | -- |
| Zipcode of the event site | 83444 |
| Event Date Year | 2010 |
| Event Date Month | 9 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 434307n |
| Event Location Longitude | 1120714w |
| Event Location Airport | Tanner Airstrip |
| Event Location Nearest Airport ID | PVT |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | 0 |
| Degrees magnetic from airport | -- |
| Airport Elevation | 4775 |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 853 Mountain Daylight Time |
| Direction of event from weather observation facility (degrees) | 200 |
| Weather Observation Facility ID | IDE |
| Elevation of weather observation facility | 4744 |
| Distance of event from weather observation facility (units?) | 18 |
| Time Zone of the weather observation | MDT |
| 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) | 12 |
| Dew Point at event time (in degress fahrenheit) | 6 |
| Wind Direction (degrees magnetic) | -- |
| Variable Wind Indicator | -- |
| Wind Speed (knots) | -- |
| Wind Velocity Indicator | Calm |
| Wind Gust Indicator | -- |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.02 |
| 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 | 1 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 28157 |
| NTSB Notification Source | FAA FSDO |
| NTSB Notification Date | -- |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | Mar 24 2011 5:44PM |
| User who most recently changed record | coos |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N4427M |
| NTSB Number | WPR10LA483 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | BOAM |
| Aircraft Model | RANS S-6S |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 08031518-S |
| Certified Max Gross Weight | -- |
| Aircraft Category | Airplane |
| Aircraft Registration Class | -- |
| Aircraft is a homebuilt? | Yes |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | 2 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | Conditional |
| Date of Last Inspection | Jul 19 2010 12:00AM |
| Airframe hours since last inspection | 16 |
| Airframe Hours | 429 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | C91-A |
| Aircraft Owner Name | BOAM LARRY |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | RIGBY |
| Aircraft Owner State | ID |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 83442-5632 |
| Operator is an individual? | Yes |
| Operator Name | BOAM LARRY |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | -- |
| Operator City | RIGBY |
| Operator State | ID |
| Operator Country | USA |
| Operator Zip code | 83442-5632 |
| 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 | Yes |
| Departure Airport Code | PVT |
| Departure City | Roberts |
| Departure State | ID |
| Departure Country | USA |
| Departure Time | 910 |
| Departure Time Zone | MDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | U56 |
| Destination City | Rigby |
| Destination State | ID |
| Destination Country | USA |
| Specific Phase of Flight | -- |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Mar 24 2011 5:45PM |
| User who most recently changed record | coos |
| Since inspection or accident | Last Inspection |
| Event Location Runway Number and Location | 20 |
| Runway Length | 1500 |
| Runway Width | 100 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |