Houston Helicopters Bell 206B accident
Bell 206B · Accident: airframe, component or system failure en route
From Bay City, TX to Houston, TX
Event
- NTSB case
- FTW87FA198
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- 0
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- Charter & commuter
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Bell 206B
- Aircraft type
- Bell 206
- Category
- Helicopter
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N33PW
- Operator
- Houston Helicopters
- Onboard fatalities
- Unknown
- Route
- From Bay City, TXTo Houston, TX
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 135: Air Taxi & Commuter
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- En route · cruise
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Airframe, component or system failure
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Pilot in command › Flare, improper
- Rotor drive system, engine to transmission drive › Failure, total
- Rotor drive system, engine to transmission drive › Overtemperature
- Rotor drive system, isolation link › Failure, total
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
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.
Verbatim NTSB analysis from the NTSB dataset
Sources
NTSB record FTW87FA198
- Event ID
- 20001213X31803
- Case number
- FTW87FA198
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: c87746abe04d24f1759488284af03211d4760c202b9f60be253c305ad964b469; retrieved 2026-09-18T19:38:43.049Z.