Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Pensacola, Florida 32504
Friday, March 16, 2012 10:15 CDT
NTSB Narrative Summary Released at Completion of Accident
During the training flight, the single-engine airplane was in cruise flight about 1,000 feet above ground level when the engine stopped operating. The flight instructor assumed control of the airplane and unsuccessfully attempted to restart the engine while descending for an emergency landing. He ditched the airplane into a nearby bay. The airplane sustained substantial damage to the windshield during the accident sequence and was submerged in salt water. Postaccident examination of the engine revealed that the bolt or lockplate, which attaches the crankshaft gear to the aft end of the crankshaft, was missing. Further, the alignment dowel was fractured across about one-third of the cross-sectional area. The bolt and lockplate were likely either not installed or were improperly installed, which would allow the bolt to loosen and become disengaged. Measurements of the dowel, pilot flange, and counterbore recess diameters were all within the manufacturer's specifications; the dowel also met the manufacturer's hardness requirement. Because the components were within manufacturer's specifications, it is likely that the components did not have any preexisting wear or manufacturing issues. Additionally, wear marks on the crankshaft, dowel, and gear were likely caused by the newly installed gear and were consistent with either no installation or improper installation of the bolt or lockplate. Therefore, it is likely that when the wear on the dowel had proceeded through about one-third of the cross-section, the stresses in the dowel became sufficiently high to initiate fatigue cracks at the base of the worn part of the dowel and eventually led to a fatigue fracture. The evidence is consistent with the failure of maintenance personnel to install, or properly install, the bolt and lockplate during the engine’s last overhaul, which resulted in the crankshaft gear becoming separated from the crankshaft and a total loss of engine power. If the engine had failed at a point that would have allowed the pilot to land the airplane on land, the airplane damage is less likely to have been substantial; therefore, contributing to the accident was the lack of suitable terrain.
NTSB Probable Cause Narrative
A total loss of engine power due to the improper installation of the crankshaft gear bolt or lockplate by maintenance personnel. Contributing to the accident was the lack of suitable terrain for a forced landing.
Event Information
| Type of Event | Accident |
| Event Date | 3/16/2012 |
| Event Day of the Week | Friday |
| Time of Event | 1015 |
| Event Time Zone | Central Daylight Time |
| Event City | Pensacola |
| Event State | FLORIDA |
| Event Country | -- |
| Zipcode of the event site | 32504 |
| Event Date Year | 2012 |
| Event Date Month | 3 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 302511N |
| Event Location Longitude | 0871135W |
| 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 | Weather Observation Facility |
| Time of the weather observation | 953 Central Daylight Time |
| Direction of event from weather observation facility (degrees) | 331 |
| Weather Observation Facility ID | PNS |
| Elevation of weather observation facility | 121 |
| Distance of event from weather observation facility (units?) | 3 |
| 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) | 23 |
| Dew Point at event time (in degress fahrenheit) | 17 |
| 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) | 30.26 |
| 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) | 31599 |
| NTSB Notification Source | FAA Southern C-ROC |
| NTSB Notification Date | -- |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | Jul 8 2013 10:23AM |
| User who most recently changed record | kenj |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N79509 |
| NTSB Number | ERA12LA234 |
| 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 | CESSNA |
| Aircraft Model | 172K |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 17258140 |
| Certified Max Gross Weight | 2450 |
| 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 | Fixed |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Oct 1 2011 12:00AM |
| Airframe hours since last inspection | -- |
| Airframe Hours | 5020 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | Unknown |
| Aircraft Owner Name | SKYWARRIOR INC |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | BAY MINETTE |
| Aircraft Owner State | AL |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 36507-3602 |
| Operator is an individual? | No |
| Operator Name | SKYWARRIOR INC |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | -- |
| Operator City | BAY MINETTE |
| Operator State | AL |
| Operator Country | USA |
| Operator Zip code | 36507-3602 |
| 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 | Yes |
| Departure Point Same as Event | Yes |
| Departure Airport Code | PNS |
| Departure City | Pensacola |
| Departure State | FL |
| Departure Country | USA |
| Departure Time | 915 |
| Departure Time Zone | CDT |
| Destination Same as Local Flt | dest & departure same, accident can occur anywhere |
| Destination Airport Code | PNS |
| Destination City | Pensacola |
| Destination State | FL |
| Destination Country | USA |
| Specific Phase of Flight | -- |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Jul 8 2013 10:23AM |
| User who most recently changed record | kenj |
| 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 | -- |