NTSB investigations: Franklin 6V4 series
11 cases on aircraft whose registry engine model is Franklin 6V4 series, where the first occurrence was “Airframe/component/system failure/malfunction”. Aircraft are matched to the registry by N-number and event date, checked against the reported serial number, make and model, so older matches can be wrong.
Cases per year
| 1982 | 2 |
|---|---|
| 1989 | 1 |
| 1991 | 1 |
| 1994 | 1 |
| 1998 | 3 |
| 2000 | 1 |
| 2001 | 1 |
| 2005 | 1 |
Where
Open the mapLatest cases
Query with SQL
duckdb -csv -c "SELECT c.\"ntsbNumber\", c.\"eventDate\", c.\"eventType\", c.\"eventCity\", c.\"eventStateOrRegion\", a.n_number, a.\"aircraftMake\", a.\"aircraftModel\", c.\"highestInjuryLevel\", c.\"totalFatal\", c.\"completionStatus\", c.report_url
FROM 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c LEFT JOIN 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' a ON a.case_mkey = c.\"mKey\" AND a.position = 1
WHERE c.\"mKey\" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('27033')
AND EXISTS (SELECT 1 FROM 'https://openairdocs.org/data/latest/ntsb_occurrences.parquet' o WHERE o.case_mkey = x.case_mkey AND o.aircrafts_position = x.position AND o.\"occurrenceNumber\" = 1 AND o.\"occurrenceCode\" = 130))
ORDER BY c.\"eventDate\" DESC, c.\"ntsbNumber\" DESC"Prints the whole list as CSV. It reads the release’s Parquet files over HTTPS, so there’s nothing to download first. Install DuckDB to run it.
SELECT c."ntsbNumber", c."eventDate", c."eventType", c."eventCity", c."eventStateOrRegion", a.n_number, a."aircraftMake", a."aircraftModel", c."highestInjuryLevel", c."totalFatal", c."completionStatus", c.report_url
FROM 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c LEFT JOIN 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' a ON a.case_mkey = c."mKey" AND a.position = 1
WHERE c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('27033')
AND EXISTS (SELECT 1 FROM 'https://openairdocs.org/data/latest/ntsb_occurrences.parquet' o WHERE o.case_mkey = x.case_mkey AND o.aircrafts_position = x.position AND o."occurrenceNumber" = 1 AND o."occurrenceCode" = 130))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESCRun it at the DuckDB prompt, or in any tool that reads Parquet over HTTPS. More ways to query the release are on Use the data.
NTSB LAX06LA030Accident · Serious injuriesLimited investigationFinal reportBell 47D1 · Rancho Murieta, CAa separation of the tail rotor assembly due to the reverse bending fatigue fracture of a tail rotor pitch change link bolt, resulting in a loss of control of the helicopter, and a hard landing during the uncontrolled descent.NTSB ATL01LA108Accident · No injuriesLimited investigationFinal reportBell 47G · Berry, ALThe failure of the main rotor system stabilizer damper control horn assembly, resulting in an uncontrolled descent and subsequent collision with a tree and terrain.NTSB MIA00LA111Accident · Minor injuriesLimited investigationFinal reportHiller UH-12B · Sanford, FLThe pilot's improper collective and cyclic control usage during an emergency descent, following the onset of a 1 to 1 vibration for undetermined reasons, resulting in the helicopter landing hard and rolling over.NTSB CHI99LA012Accident · No injuriesLimited investigationFinal reportHiller UH-12C · Clinton, IAthe failure of the 90 degree gearbox for reasons undetermined. Factors were the failure of the gearbox, and it not being possible for the pilot to maintain control of the aircraft.NTSB MIA98LA254Accident · Minor injuriesLimited investigationFinal reportBell 47-D1 · Oxford, MSThe pilot's failure to maintain directional control due to vibration from the main rotor blade for undetermined reasons. A related finding was the improper repair of a crack in the laminant of the blue main rotor blade by other maintenance personnel.NTSB FTW98LA144Accident · Minor injuriesLimited investigationFinal reportBell 47D1 · Jeanerette, LAThe in-flight disconnect of the rotating scissors due to the separation of its hinge bolt.NTSB MIA94FA125Accident · 2 fatalField investigationFinal reportBell 47D1 · Marathon, FLSeparation of the tail rotor gearbox and tail rotor blades for an undetermined reason. Factors related to the accident were: failure of maintenance personnel to follow the proper maintenance procedure after a previous tail rotor strike, and failure to conduct…NTSB ATL92LA017Accident · No injuriesLimited investigationFinal reportBell 47D-1 · Rome, GAThe failure of a tail rotor blade for undetermined reasons.NTSB ATL89DLT03Accident · No injuriesFinal reportBell 47 · Shelbyville, TNFailure in the rotor drive system for unknown reasons. Contributing to the accident was the pilot's inability to perform an autorotation.NTSB LAX82FA341Accident · Minor injuriesField investigationFinal reportBell 47G-2 · San Diego, CAThe plt was in the local pattern practicing maneuvers. After completing a quick stop maneuver & hovering, another takeoff was initiated. The plt stated that it seemed to take an unusual amount of forward cyclic to initiate forward flt. During the final…NTSB NYC82DA087Accident · No injuriesFinal reportHiller UH-12A · New Paltz, NYWhile cruising at 400 ft AGL, the pilot noticed a decay in the main rotor RPM; however, the engine RPM was reported to have remained constant. The pilot suspected a mechanical failure and elected to make a precautionary landing in an apple orchard. During the…