Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Pledger, Texas 77468
Wednesday, August 12, 1987 16:20 CDT
NTSB Narrative Summary Released at Completion of Accident
WHILE CRUISING AT 900' AGL, THE PLT NOTED A HVY SHUDDER FLWD BY A GRINDING NOISE, LOUD 'BANG' & A LOW ROTOR RPM SIGNAL. HE MADE AN AUTOROTATION TO A ROAD, BUT DRG TOUCHDOWN, THE MAIN ROTOR BLADES FLEXED DWN & SEVERED THE TAIL BOOM. AN EXAM REVEALED THE MAIN PWR (SHORT) SHAFT HAD FAILED DUE TO MISALIGNMENT & HI TEMPS RESULTING FROM THE MISALIGNMENT. FURTHER INV SHOWED THAT THE MISALIGNMENT WAS THE RESULT OF A FAILURE OF THE PYLON ISOLATOR MOUNT DUE TO DEBONDING BETWEEN THE UPPER PLATE & THE RUBBER DAMPER ELEMENT. DEBONDING OCCURRED AFTER PROLONGED EXPOSURE OF THE ISOLATOR MOUNT TO OIL & GREASE WHICH CHEMICALLY DETERIORATED THE BOND. THERE WAS EVIDENCE THE DETERIORATION HAD OCCURRED OVER A LONG PERIOD OF TIME. THE UNIT HAD BEEN INSPECTED PERIODICALLY, BUT THE IMPENDING FAILURE OF THE BOND HAD NOT BEEN DETECTED.
NTSB Probable Cause Narrative
Not Yet Reported
Event Information
| Type of Event | Accident |
| Event Date | 8/12/1987 |
| Event Day of the Week | Wednesday |
| Time of Event | 1620 |
| Event Time Zone | Central Daylight Time |
| Event City | PLEDGER |
| Event State | TEXAS |
| Event Country | -- |
| Zipcode of the event site | 77468 |
| Event Date Year | 1987 |
| Event Date Month | 8 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | |
| Event Location Longitude | |
| 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 | 0 |
| Degrees magnetic from airport | 0 |
| Airport Elevation | 0 |
| Weather Briefing Completeness | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1552 Central Daylight Time |
| Direction of event from weather observation facility (degrees) | 30 |
| Weather Observation Facility ID | HOU |
| Elevation of weather observation facility | 39 |
| Distance of event from weather observation facility (units?) | 25 |
| Time Zone of the weather observation | CDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 0 |
| Lowest Non-Ceiling Height | 4000 |
| Sky/Lowest/Cloud Conditions | Scattered |
| Sky Condition for Lowest Ceiling | None |
| Visibility Runway Visual Range (Feet) | 0 |
| Visibility Runway Visual Value (Statute Miles) | 0 |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 36 |
| Dew Point at event time (in degress fahrenheit) | 21 |
| Wind Direction (degrees magnetic) | 180 |
| Variable Wind Indicator | Unknown |
| Wind Speed (knots) | 6 |
| Wind Velocity Indicator | Unknown |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | 0 |
| Altimeter Setting at event time (in. Hg) | 29 |
| Density Altitude (feet) | 2250 |
| Intensity of Precipitation | Unknown |
| METAR weather report | -- |
| Event Highest Injury | None |
| On Ground, Fatal Injuries | 0 |
| On Ground, Minor Injuries | 0 |
| On Ground, Serious Injuries | 0 |
| Injury Total Fatal | -- |
| Injury Total Minor | -- |
| Injury Total None | 4 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 2415 |
| NTSB Notification Source | -- |
| NTSB Notification Date | Aug 13 1987 12:00AM |
| NTSB Notification Time | 730 |
| Fiche Number and/or location -used to find docket information | 36414 |
| Date of most recent change to record | Dec 13 2000 2:43PM |
| User who most recently changed record | dbo |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N33PW |
| NTSB Number | FTW87FA198 |
| Missing Aircraft Indicator | N |
| Federal Aviation Reg. Part | Part 135: Air Taxi & Commuter |
| Type of Flight Plan filed | Company VFR |
| Flight plan Was Activated? | -- |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | BELL |
| Aircraft Model | 206B |
| Aircraft Series Identifier | 206B |
| Aircraft Serial Number | 2223 |
| Certified Max Gross Weight | 3200 |
| Aircraft Category | Helicopter |
| Aircraft Registration Class | U.S. Registered/U.S. Soil |
| Aircraft is a homebuilt? | No |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | 5 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | AAIP |
| Date of Last Inspection | Aug 1 1986 12:00AM |
| Airframe hours since last inspection | 91 |
| Airframe Hours | 4468 |
| ELT Installed | No |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | NOTLET, INC. |
| Aircraft Owner Street Address | 211 BYERS RD. |
| Aircraft Owner City | PORT O'CONNOR |
| Aircraft Owner State | TX |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | 77982 |
| Operator is an individual? | -- |
| Operator Name | HOUSTON HELICOPTERS |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | P.O. BOX 830 |
| Operator City | PEARLAND |
| Operator State | TX |
| Operator Country | |
| Operator Zip code | |
| Operator Code | |
| Owner has at least one certificate | Yes - certificate holder |
| Other Operator of large aircraft? | No |
| Certified for Part 133 or 137 Operation | Unknown |
| Operator Certificate Number | -- |
| Indicates whether an air carrier operation was scheduled or not | Non-scheduled |
| Indicates Domestic or International Flight | Domestic |
| Operator carrying Pax/Cargo/Mail | Passenger Only |
| Type of Flying (Per_Bus / Primary) | Unknown |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | |
| Departure City | BAY CITY |
| Departure State | TX |
| Departure Country | |
| Departure Time | 1600 |
| Departure Time Zone | CDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | |
| Destination City | HOUSTON |
| Destination State | TX |
| Destination Country | |
| Specific Phase of Flight | Landing |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Jan 2 2001 10:35AM |
| User who most recently changed record | dbo |
| Since inspection or accident | -- |
| Event Location Runway Number and Location | 0 |
| Runway Length | 0 |
| Runway Width | 0 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |