Individually Owned: 150,657
Corporate Owned: 137,281
Pueblo Memorial Airport
Aircraft Accident/Incident Report
Pueblo, Colorado 81001
Tuesady, March 6, 2007 9:00 MST
NTSB Narrative Summary Released at Completion of Accident
The flight instructor reported that abnormal nose-up trim was required while in flight. The flight concluded without additional or further incidence. After the training flight a 2 to 3-inch gap between the horizontal and vertical stabilizer was noted. Examination of the airplane revealed two bolts, securing the front horizontal stabilizer mounting bracket to the vertical stabilizer, had failed. Examination of the bolts revealed failure due to undetected fatigue. On the failed bolts, the sizes of the final overstress regions were very small indicating that peak and mean loads on the bolts were also small. This would indicate that only a small or marginal preload was present on the bolts. Insufficient preload could be the result of low installation torque or the loss of preload during service. The off center wear on the washers suggests that the fastened surfaces may not have been in alignment allowing the installation preload to quickly degrade.
NTSB Probable Cause Narrative
The failure of the horizontal stabilizer forward bracket bolts due to insufficent preload during factory installation.
Event Information
| Type of Event | Incident |
| Event Date | 3/6/2007 |
| Event Day of the Week | Tuesday |
| Time of Event | 900 |
| Event Time Zone | Mountain Standard Time |
| Event City | Pueblo |
| Event State | COLORADO |
| Event Country | -- |
| Zipcode of the event site | 81001 |
| Event Date Year | 2007 |
| Event Date Month | 3 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 381730N |
| Event Location Longitude | 1070340W |
| Event Location Airport | PUEBLO MEMORIAL |
| Event Location Nearest Airport ID | PUB |
| Indicates whether the acc/inc occurred off or on an airport | On Airport |
| Distance from airport in statute miles | 1 |
| Degrees magnetic from airport | -- |
| Airport Elevation | 4726 |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 953 Mountain Standard Time |
| Direction of event from weather observation facility (degrees) | 360 |
| Weather Observation Facility ID | KPUB |
| Elevation of weather observation facility | 4726 |
| Distance of event from weather observation facility (units?) | 1 |
| Time Zone of the weather observation | MST |
| 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) | 6 |
| Dew Point at event time (in degress fahrenheit) | -14 |
| 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) | 30.15 |
| 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) | 23281 |
| NTSB Notification Source | Doss Aviation |
| NTSB Notification Date | Mar 7 2007 12:00AM |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Mar 31 2008 11:52AM |
| User who most recently changed record | NTSB\johb |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N921DA |
| NTSB Number | DEN07IA066 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | None |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Diamond Aircraft Industries |
| Aircraft Model | DA-20-C1 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | C0395 |
| Certified Max Gross Weight | 1764 |
| 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 | 2 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | 100 Hour |
| Date of Last Inspection | Feb 1 2007 12:00AM |
| Airframe hours since last inspection | -- |
| Airframe Hours | 189 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | Doss Aviation Inc. |
| Aircraft Owner Street Address | 3320 W Carefree Cir. |
| Aircraft Owner City | Colorado Springs |
| Aircraft Owner State | CO |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 80917 |
| 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) | Instructional |
| Second Pilot on Board | Yes |
| Departure Point Same as Event | Yes |
| Departure Airport Code | KPUB |
| Departure City | Pueblo |
| Departure State | CO |
| Departure Country | USA |
| Departure Time | 800 |
| Departure Time Zone | MST |
| Destination Same as Local Flt | crash at destination city |
| Destination Airport Code | KPUB |
| Destination City | Pueblo |
| Destination State | CO |
| Destination Country | USA |
| Specific Phase of Flight | Cruise |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Nov 28 2007 9:45AM |
| User who most recently changed record | BOWL |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | 26L |
| Runway Length | 4073 |
| Runway Width | 75 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |