# NTSB investigations: Franklin 6V4 series NTSB aviation accident and incident investigations since 1962: the probable cause, findings, aircraft, crew, weather and docket of each, linked to the FAA registry and the FAA’s own reports. Page 2 of 6 · 285 cases ## Cases, newest first - [NTSB ATL92LA017](https://openairdocs.org/ntsb/ATL92LA017.md): Bell 47D-1 · Rome, GA · Accident · No injuries · Limited investigation · Final report · Oct 28, 1991 · N925V · Substantial damage > The failure of a tail rotor blade for undetermined reasons. - [NTSB SEA91LA233](https://openairdocs.org/ntsb/SEA91LA233.md): Bell 47G · Miltonfreewater, OR · Accident · Minor injuries · Limited investigation · Final report · Sep 12, 1991 · N73865 · Substantial damage > Pilot factor in that the pilot failed to insure there was adequate clearance from obstacles for a safe takeoff. A factor to the accident was: the pilot's poor preflight planning/preparation. - [NTSB CHI90DEC04](https://openairdocs.org/ntsb/CHI90DEC04.md): Bell 47 D-1 · Stockbridge, MI · Accident · Serious injuries · Final report · Aug 14, 1990 · N3656F · Destroyed > The restricted visual lookout which resulted from the canopy fogging up. - [NTSB NYC90DGM02](https://openairdocs.org/ntsb/NYC90DGM02.md): Bell 47D1 · Meadville, PA · Accident · 1 fatal · Final report · Jun 22, 1990 · N310A · Destroyed > The pilot's failure to see and avoid the power lines. - [NTSB BFO90LA042](https://openairdocs.org/ntsb/BFO90LA042.md): Bell 47D · Baltimore, MD · Accident · No injuries · Limited investigation · Final report · May 13, 1990 · N4229A · Substantial damage > The pilot applied excessive cyclic control, causing the main rotor to flex and severe the tail cone. - [NTSB MIA90LA111](https://openairdocs.org/ntsb/MIA90LA111.md): Hiller UH-12B · Sanford, FL · Accident · No injuries · Limited investigation · Final report · Apr 26, 1990 · N5306V · Substantial damage > Loss of engine power for an unknown reason. - [NTSB ATL90DLQ01](https://openairdocs.org/ntsb/ATL90DLQ01.md): Bell 47D1 · Hickman, KY · Accident · No injuries · Final report · Apr 24, 1990 · N2134 · Substantial damage > Improper in-flight planning/decision by the pilot. The resultant tailwind was a related factor. - [NTSB MIA90LA023](https://openairdocs.org/ntsb/MIA90LA023.md): Bell 47D1 · Loxahatchee, FL · Accident · Serious injuries · Limited investigation · Final report · Nov 2, 1989 · N93067 · Substantial damage > Failure of the pilot to maintain rotor RPM after pulling up from a swath run. A related factor was the presence of trees. - [NTSB MKC89LA195](https://openairdocs.org/ntsb/MKC89LA195.md): Bell 47G · Ozark, MO · Accident · No injuries · Limited investigation · Final report · Sep 2, 1989 · N182JR · Substantial damage > The failure of the dual student to properly flare during an autorotative landing resulting in a hard landing and partial failure of the right skid. The CFI also failed to properly monitor the student's actions on the flight controls. - [NTSB SEA89LA120](https://openairdocs.org/ntsb/SEA89LA120.md): Bell 47G-2 · Centralia, WA · Accident · Minor injuries · Limited investigation · Final report · Jun 24, 1989 · N1161N · Destroyed > The pilot misjudged his clearance over trees, which resulted in an in-flight tail rotor strike with the trees and loss of tail rotor control. The trees were a related factor. - [NTSB ATL89DLT03](https://openairdocs.org/ntsb/ATL89DLT03.md): Bell 47 · Shelbyville, TN · Accident · No injuries · Final report · May 12, 1989 · N908B · Substantial damage > Failure in the rotor drive system for unknown reasons. Contributing to the accident was the pilot's inability to perform an autorotation. - [NTSB MIA89LA133](https://openairdocs.org/ntsb/MIA89LA133.md): Bell 47D1 · Miami, FL · Accident · Serious injuries · Limited investigation · Final report · Apr 17, 1989 · N342L · Substantial damage > The unqualified persons failure to maintain clearance from the fence. Pressure induced by others, lack of experience, and over confidence in personal ability are contributing factors to this accident. - [NTSB FTW89DPA03](https://openairdocs.org/ntsb/FTW89DPA03.md): Bell 47-D1 · Allen, TX · Accident · Serious injuries · Final report · Dec 2, 1988 · N74124 · Substantial damage > Unqualified pilot's poor judgement in leveling the helicopter during the flare and contributing to this was his lack of total experience in this type aircraft. - [NTSB MIA88LA212](https://openairdocs.org/ntsb/MIA88LA212.md): Bell 47D1 · Ruleville, MS · Accident · No injuries · Limited investigation · Final report · Jul 4, 1988 · N903B · Substantial damage > During an aerial application flt while spraying chemicals the plt reported that the engine quit. The pilot attempted an autorotation but was too low and slow to complete it. The aircraft landed hard in the field of crops and nosed over. Examination of the… - [NTSB LAX88LA160](https://openairdocs.org/ntsb/LAX88LA160.md): Bell 47D1 · Taft, CA · Accident · No injuries · Limited investigation · Final report · Apr 13, 1988 · N917B · Substantial damage - [NTSB MKC88FA054](https://openairdocs.org/ntsb/MKC88FA054.md): Bell 47D1 · Nixa, MO · Accident · 1 fatal · Field investigation · Final report · Feb 21, 1988 · N7735 · Destroyed > During the process of moving the helicopter from the hangar the right skid slipped off the concrete helipad and became stuck in the mud. The pilot attempted to dislodge the skid by bringing the aircraft to a hover. The left skid became airborne and contacted… - [NTSB SEA87LA172](https://openairdocs.org/ntsb/SEA87LA172.md): Bell 47G2 · Grandview, WA · Accident · Serious injuries · Limited investigation · Final report · Aug 21, 1987 · N74161 · Substantial damage > After the completion of spray operations the pilot was attempting to place the helicopter onto a trailer. The pilot misjudged his position, over-corrected, and then lost control of the helicopter, striking the ground. - [NTSB LAX87LA294](https://openairdocs.org/ntsb/LAX87LA294.md): Bell 47D-1 · Taft, CA · Accident · No injuries · Limited investigation · Final report · Aug 5, 1987 · N917B · Substantial damage > The plt rprtd the eng lost power at about 300' AGL after the helicopter had flown aprx 2.7 hrs without refueling. He initiated an autorotative landing; however, before touchdown, the main rotor blades contacted & severed the tail boom. An exam revealed the… - [NTSB ATL87LA204](https://openairdocs.org/ntsb/ATL87LA204.md): Bell 47D1 · Huntsville, AL · Accident · No injuries · Limited investigation · Final report · Jul 8, 1987 · N908B · Substantial damage > The aerial application flight was dispensing insecticides on a cotton field. While maneuvering to avoid powerlines during the procedure turnaround following an upwind swath run, the pilot failed to maintain sufficient airspeed to ensure effective… - [NTSB ATL87DEI05](https://openairdocs.org/ntsb/ATL87DEI05.md): Bell 47G-2 · Lisbon, OH · Accident · Minor injuries · Final report · Jun 14, 1987 · N984B · Substantial damage > The helicopter rolled over as it was lifting off from a transport trailer. A post-crash exam revealed that the left rear tie-down strap on the trailer was wrapped around one of the helicopter skids. The ground crewman believed he had removed all of the straps… - [NTSB ATL86FEI07](https://openairdocs.org/ntsb/ATL86FEI07.md): Bell 47G2 · Lisbon, OH · Accident · 1 fatal · Final report · Jun 26, 1986 · N984B · Minor damage > The aerial application helicopter was being serviced by a chemical truck that was parked adjacent to the acft. The acft engine was at high idle with the main rotor turning at 250 RPM. The ground crewman jumped off the side of the chemical truck into the main… - [NTSB LAX85LA249](https://openairdocs.org/ntsb/LAX85LA249.md): Hiller 12-C · Casa Grande, AZ · Accident · No injuries · Limited investigation · Final report · May 9, 1985 · N38767 · Substantial damage > The plt was demonstrating autorotations to a touchdown on a dirt rwy into a 5 kt headwind. On the final landing he said that the touchdown felt the same as others he had done. Speed at touchdown was 15 mph and the helicopter slid forward in a straight line… - [NTSB LAX85LA079](https://openairdocs.org/ntsb/LAX85LA079.md): Bell 47G · Chatsworth, CA · Accident · No injuries · Limited investigation · Final report · Dec 22, 1984 · N182JR · Destroyed > The plt was practicing off airport touch & go's. on the second lndg the left skid contacted a hidden dirt embankment andthe acft rolled over. A post impact fire consumed the aircraft. Both certificated commercial plts aboard the helicopter escaped unharmed.… - [NTSB FTW85LA074](https://openairdocs.org/ntsb/FTW85LA074.md): Bell 47D1 · Ardmore, OK · Accident · Serious injuries · Limited investigation · Final report · Dec 7, 1984 · N5226 · Substantial damage > The acft collided with power lines during a recovery from a practice autorotational landing. The instructor plt took control of the acft for recovery and did not see the wires. - [NTSB FTW85LA043](https://openairdocs.org/ntsb/FTW85LA043.md): Bell 47D1 · Terlingua, TX · Accident · No injuries · Limited investigation · Final report · Nov 4, 1984 · N93067 · Substantial damage > Shortly after the plt took off on a sight-seeing flt, the eng lost power when the helicopter was over rough terrain at about 200 ft AGL. During an autorotative landing, the helicopter rocked forward causing the main rotor blades to strike the tail boom.… - [NTSB CHI84LA184](https://openairdocs.org/ntsb/CHI84LA184.md): Bell 47D1 · Alpena, MI · Accident · Serious injuries · Limited investigation · Final report · May 20, 1984 · N9158R · Destroyed > Prior to the accident, the owner/plt of the helicopter reportedly 'buzzed' a local baseball game. Shortly after that, the helicopter was observed to maneuver over a wooded area, enter a nose high attitude, then roll or bank & enter a descent into a wooded… - [NTSB CHI84LA181](https://openairdocs.org/ntsb/CHI84LA181.md): Bell 47D-1 · Ridge Farm, IL · Accident · No injuries · Limited investigation · Final report · May 6, 1984 · N13012 · Substantial damage > The helicopter rolled over after a hard landing following loss of rotor RPM. The plt reported that during initial climb at about 300 ft AGL the rotor decreased about 500 RPM. He tried to regain rotor RPM until about 100 ft AGL and then tried an autorotation.… - [NTSB MIA84FA058](https://openairdocs.org/ntsb/MIA84FA058.md): Hiller UH-12C · San Juan, PR · Accident · 1 fatal · Field investigation · Final report · Jan 12, 1984 · N5317V · No damage > A performer fell from a trapeze rigged below the helicopter while it was hovering at about 150 ft AGL. The FAA had not authorized the modification to the acft. The plt was not certified for external load operations. The performer reportedly had not done this… - [NTSB LAX84LA108](https://openairdocs.org/ntsb/LAX84LA108.md): Bell 47G · El Cajon, CA · Accident · No injuries · Limited investigation · Final report · Dec 21, 1983 · N4475 · Substantial damage > During a demonstration to show his student how to autorotate fm a 2 ft height AGL the instructor reduced pwr and inadvertently applied fwd cyclic. The front portion of the skids hit the gd followed by the main rotor blades. Helicopter then rocked backwards,… - [NTSB SEA83LA069](https://openairdocs.org/ntsb/SEA83LA069.md): Continental Copters Mkiii · Pasco, WA · Accident · No injuries · Limited investigation · Final report · Apr 1, 1983 · N73865 · Substantial damage > While repositioning the helicopter from the ground onto a trailer the acft rolled over when the right skid caught onto the trailer. - [NTSB DEN83LA007](https://openairdocs.org/ntsb/DEN83LA007.md): Hiller UH-12C · Blanding, UT · Accident · No injuries · Limited investigation · Final report · Oct 12, 1982 · N5316V · Destroyed > The private single-engine pilot had a student helicopter certificate. He took off to hover and check that the helicopter was in good condition. He stated that before takeoff, the helicopter was fueled with a 5 gallon can that had been painted red. Before… - [NTSB LAX82FA341](https://openairdocs.org/ntsb/LAX82FA341.md): Bell 47G-2 · San Diego, CA · Accident · Minor injuries · Field investigation · Final report · Sep 11, 1982 · N4242A · Destroyed > The 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 CHI82DA196](https://openairdocs.org/ntsb/CHI82DA196.md): Bell 47D1 · Le Sueur, MN · Accident · No injuries · Final report · May 29, 1982 · N4251A · Substantial damage > During a spraying operation, the aircraft was being refueled from a 200 gal fuel tank, mounted on the rear of a truck. The truck was parked on a slight slope with the outlet for the servicing hose at the lower end. After the helicopter was serviced with 14… - [NTSB FTW82DA198](https://openairdocs.org/ntsb/FTW82DA198.md): Bell 47D1 · Jonesboro, AR · Accident · No injuries · Final report · May 25, 1982 · N6851 · Destroyed > After loading 40 gallons of herbicide on the aircraft the pilot attempted to lift off the back of the loading truck. The takeoff was normal; however, as the helicopter cleared the truck, it was not able to sustain a hover. The pilot then executed a running… - [NTSB FTW82DA189](https://openairdocs.org/ntsb/FTW82DA189.md): Bell 47D-1 · Harrisburg, AR · Accident · No injuries · Final report · May 20, 1982 · N93067 · Substantial damage > During an agricultural spraying operation the pilot turned downwind and the tail rotor struck a rice dike. The pilot lost control and the aircraft landed hard. The main rotor severed the tail boom. Investigation revealed the aircraft had been loaded within… - [NTSB CHI82DA176](https://openairdocs.org/ntsb/CHI82DA176.md): Bell 47G-1 · Cincinnati, OH · Accident · Minor injuries · Final report · May 20, 1982 · N141B · Substantial damage > The fore and aft cyclic control linkage tube became disconnected in flight. An emergency descent, using collective "s" turns to reduce airspeed was performed. The pilot intentionally collided with trees during the forced landing to cushion the fall.… - [NTSB NYC82DA087](https://openairdocs.org/ntsb/NYC82DA087.md): Hiller UH-12A · New Paltz, NY · Accident · No injuries · Final report · May 2, 1982 · N116S · Substantial damage > While 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… - [NTSB FTW82DA073](https://openairdocs.org/ntsb/FTW82DA073.md): Bell 47G · Dallas, TX · Accident · No injuries · Final report · Feb 28, 1982 · N1773 · Substantial damage > The pilot attempted to land on a narrow flatbed trailer. He stated that he encountered some buffeting from the wind funneling between two hangars. On his third attempt to position the helicopter on the trailer, the right skid slipped off. The main rotor… - [NTSB LAX81FUJ85](https://openairdocs.org/ntsb/LAX81FUJ85.md): Bell 47D1 · Poston, AZ · Accident · Minor injuries · Closed · Aug 10, 1981 · N8060E · Substantial damage - [NTSB MKC81DCQ43](https://openairdocs.org/ntsb/MKC81DCQ43.md): Bell 47G-2 · Sublette, KS · Accident · No injuries · Closed · Jun 20, 1981 · N7735 · Substantial damage - [NTSB SEA81FYP12](https://openairdocs.org/ntsb/SEA81FYP12.md): Bell 47G-2 · Union Gap, WA · Accident · No injuries · Closed · Apr 2, 1981 · N74161 · Substantial damage - [NTSB FTW81FA045](https://openairdocs.org/ntsb/FTW81FA045.md): Bell 47D1 · Roanoke, TX · Accident · Minor injuries · Closed · Feb 10, 1981 · N9736Z · Substantial damage - [NTSB LAX81DUG05](https://openairdocs.org/ntsb/LAX81DUG05.md): Hiller Acft UH-12B · Rialto, CA · Accident · No injuries · Closed · Nov 18, 1980 · N5310V · Destroyed - [NTSB LAX80DVA64](https://openairdocs.org/ntsb/LAX80DVA64.md): Bell 47G · Bakersfield, CA · Accident · No injuries · Closed · Aug 23, 1980 · N148B · Substantial damage - [NTSB CHI80FEC26](https://openairdocs.org/ntsb/CHI80FEC26.md): Bell 47D1 · Munith, MI · Accident · 1 fatal · Closed · Jul 30, 1980 · N3656F · Substantial damage - [NTSB CHI80DEV30](https://openairdocs.org/ntsb/CHI80DEV30.md): Bell 47D-1 · Rantoul, IL · Accident · No injuries · Closed · Jul 28, 1980 · N8271E · Substantial damage - [NTSB FTW80FPM14](https://openairdocs.org/ntsb/FTW80FPM14.md): Bell 47G · Calvin, OK · Accident · 1 fatal · Closed · Jul 16, 1980 · N16657 · Destroyed - [NTSB LAX80FVM17](https://openairdocs.org/ntsb/LAX80FVM17.md): Bell 47D1 · Salinas, CA · Accident · No injuries · Closed · Mar 9, 1980 · N78900 · Substantial damage - [NTSB LAX80FUQ11](https://openairdocs.org/ntsb/LAX80FUQ11.md): Bell 47G · Pacoima, CA · Accident · No injuries · Closed · Feb 26, 1980 · N182JR · Substantial damage - [NTSB NYC80FHD07](https://openairdocs.org/ntsb/NYC80FHD07.md): Hiller UH12B · Mount Holly, NJ · Accident · No injuries · Closed · Nov 6, 1979 · N10195 · Substantial damage Next page: https://openairdocs.org/ntsb.md?engine=27033&page=3 ## The whole list in SQL Runs in DuckDB 1.2 or later on the release's Parquet files over HTTPS: ```sql 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')) ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC ``` This list as a web page: https://openairdocs.org/ntsb?engine=27033&page=2 --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.