Individually Owned: 150,657
Corporate Owned: 137,281
Spirit Of St Louis Airport
Aircraft Accident/Incident Report
Chesterfield, Missouri 63005
Saturday, May 26, 2012 12:20 CDT
NTSB Narrative Summary Released at Completion of Accident
The pilot reported that the helicopter started to shake as he increased power for takeoff on the solo instructional flight. He reduced engine power, but the oscillations became stronger and ultimately uncontrollable, resulting in substantial damage to the main and tail rotor blades, partial separation of the main rotor mast from the aft fuselage structure, and partial separation of the tail boom from the fuselage. The pilot shut down the engine and exited the helicopter. The pilot was receiving training for the addition of a helicopter rating and was operating the helicopter under the authority of a logbook solo endorsement. Postaccident testing revealed that all four landing gear dampers failed to meet the manufacturer’s specifications. The forward dampers were undercharged, while the aft dampers were overcharged. Maintenance records indicated that the aft dampers had been replaced with overhauled units about 1 month before the accident. The forward dampers had not been replaced. Maintenance procedures required periodic inspection of the landing gear dampers, and the operator stated that the inspection procedure was accomplished after installation of the overhauled dampers. A review of the overhaul procedure for the landing gear dampers revealed that the procedure did not provide for functional testing of the dampers following overhaul, which would have identified the out-of-specification condition before installation.
NTSB Probable Cause Narrative
The undercharged and overcharged landing gear dampers, which allowed initiation of the ground resonance event from which the pilot was unable to recover due to his limited experience in helicopters. Contributing to the accident was the ineffective damper inspection conducted by the operator’s maintenance personnel and the improper overhaul procedure by the overhaul facility that resulted in overcharged dampers being provided to the operator. Also contributing was the lack of any final acceptance testing criteria for the dampers in the manufacturer’s overhaul procedure manual.
Event Information
| Type of Event | Accident |
| Event Date | 5/26/2012 |
| Event Day of the Week | Saturday |
| Time of Event | 1220 |
| Event Time Zone | Central Daylight Time |
| Event City | Chesterfield |
| Event State | MISSOURI |
| Event Country | -- |
| Zipcode of the event site | 63005 |
| Event Date Year | 2012 |
| Event Date Month | 5 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 383944N |
| Event Location Longitude | 0903907W |
| Event Location Airport | Spirit of St Louis |
| Event Location Nearest Airport ID | SUS |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | 5 |
| Degrees magnetic from airport | -- |
| Airport Elevation | 463 |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1243 Central Daylight Time |
| Direction of event from weather observation facility (degrees) | 180 |
| Weather Observation Facility ID | SUS |
| Elevation of weather observation facility | 463 |
| Distance of event from weather observation facility (units?) | 5 |
| Time Zone of the weather observation | CDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | 4000 |
| Sky/Lowest/Cloud Conditions | Few |
| 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) | 32 |
| Dew Point at event time (in degress fahrenheit) | 21 |
| 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) | 30.01 |
| 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) | 31080 |
| NTSB Notification Source | FAA -- STL FSDO |
| NTSB Notification Date | -- |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | May 23 2013 11:41AM |
| User who most recently changed record | coln |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N345MH |
| NTSB Number | CEN12LA353 |
| 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 | None |
| Aircraft Manufacturer's Full Name | SCHWEIZER |
| Aircraft Model | 269C-1 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 0173 |
| Certified Max Gross Weight | 1750 |
| Aircraft Category | Helicopter |
| Aircraft Registration Class | -- |
| Aircraft is a homebuilt? | No |
| 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 | 100 Hour |
| Date of Last Inspection | Apr 11 2012 12:00AM |
| Airframe hours since last inspection | 62 |
| Airframe Hours | 4200 |
| ELT Installed | No |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | My Sky LLC |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | Chesterfield |
| Aircraft Owner State | MO |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 63005 |
| Operator is an individual? | No |
| Operator Name | My Sky LLC |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | -- |
| Operator City | Chesterfield |
| Operator State | MO |
| Operator Country | USA |
| Operator Zip code | 63005 |
| 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) | Instructional |
| Second Pilot on Board | No |
| Departure Point Same as Event | Yes |
| Departure Airport Code | SUS |
| Departure City | Chesterfield |
| Departure State | MO |
| Departure Country | USA |
| Departure Time | 1215 |
| Departure Time Zone | CDT |
| Destination Same as Local Flt | dest & departure same, accident can occur anywhere |
| Destination Airport Code | SUS |
| Destination City | Chesterfield |
| Destination State | MO |
| Destination Country | USA |
| Specific Phase of Flight | -- |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Feb 4 2013 11:07AM |
| User who most recently changed record | sort |
| 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 | -- |