# NTSB NYC94LA050: Bell 47G-5, N7043J, Plymouth, MA, March 1, 1994 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: March 1, 1994, 15:35 local (20:35 UTC) - Place: Plymouth, MA - Location: 41.9088° N, 70.7276° W: Placed by OpenAirDocs at PLYMOUTH MUNI (PYM), within about a mile (OpenAirDocs) - Nearby events: https://openairdocs.org/map.md?lat=41.9088&lon=-70.7276&mi=10 - Phase of flight: [Standing](https://openairdocs.org/ntsb-phases/150) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious, 1 uninjured - Status: Completed, report November 18, 1994 - Report: Approved by Office Director - NTSB case key (mKey): 38730 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC94LA050 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/38730/pdf - Page: https://openairdocs.org/ntsb/NYC94LA050 ## Probable cause The pilot's failure to maintain adequate clearance of the fuel truck from the aircraft, which resulted in the main rotor striking the fuel hose and truck during refueling operation. A factor was the pilot's failure to follow company policy pertaining to the refueling of aircraft. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - On ground/water collision with object, standing - idling rotors - object - vehicle - clearance - not maintained, flight instructor(on ground) (cause) - procedures/directives - not followed, flight instructor(on ground) (contributing factor) ## Analysis THE STUDENT PILOT WAS RECEIVING INSTRUCTION IN THE BELL 47 HELICOPTER FROM A CERTIFIED FLIGHT INSTRUCTOR (CFI). AFTER A 1.5 HOUR DUAL INSTRUCTION FLIGHT, THE STUDENT AND THE CFI RETURNED TO THE DEPARTURE AIRPORT TO REFUEL, AND WERE PLANNING TO DEPART AGAIN FOR ANOTHER TRAINING FLIGHT. AFTER LANDING, THE HELICOPTER WAS LEFT IDLING WITH THE RSP AT THE CONTROLS WHILE THE CFI EXITED THE HELICOPTER TO RETRIEVE THE FUEL TRUCK. THE CFI RETURNED WITH THE FUEL TRUCK, RE-FUELED THE HELICOPTER AND WAS RETURNING THE FUEL HOSE TO THE TRUCK WHEN THE TURNING ROTOR BLADES STRUCK THE HOSE AND FUEL TRUCK. THE HOSE IN TURN STRUCK THE CFI. THE INVESTIGATION REVEALED THAT THE TRUCK HAD BEEN PARKED ABOUT 3.5 FEET FROM THE TURNING ROTOR BLADES, AND COMPANY POLICY MANDATED A MINIMUM OF A 10 FOOT CLEARANCE. RE-ENACTMENT OF THE HOSE STOWAGE TO THE SIDE OF THE FUEL TRUCK SHOWED A TENDENCY FOR THE HOSE TO DEFLECT UP INTO THE ROTOR TIP PATH PLANE. ## Factual narrative On March 1, 1994, at about 1535 eastern standard time, a Bell 47G5 Helicopter, N7043J, owned and operated by Plymouth Copters, was substantially damaged during a refueling operation while the helicopter was idling at the Plymouth Airport, Plymouth, Massachusetts. The pilot at the controls was not injured, but the instructor pilot operating the fuel truck received serious injuries. Visual meteorological conditions prevailed. A flight plan had not been filed for the flight operating under 14 CFR 91. The rated student pilot (RSP), John Christopher, was receiving instruction in the Bell 47G5, to qualify him for insurance purposes for the Bell 47G2 that he had recently purchased. The flight instructor/owner of Plymouth Copters Robert Dumas, and the RSP, departed the Plymouth Airport (PYM) in N7043J about 1400, for a local training flight. After a 1 1/2 hour flight, they returned to PYM to refuel the helicopter, and were planning to depart again for another 1 1/2 hour training flight. In his statement, the RSP stated: "...[Mr. Dumas] said that he would pull up along side of the helicopter, and re-fuel it without shutting it down. I gave him a look of disapproval to which he responded, 'We do this all the time'. I landed on the pad, the helicopter well centered...Mr. Dumas left the helicopter. I began applying collective friction. Before I engaged cyclic friction Mr. Dumas had already pulled along side of the helicopter and re-entered the cabin. He said to move the cyclic forward slightly and to hold it there, which I did. I watched ...the re-fueling, and the stowing of the hose. The fuel truck had side boards along its length approximately 6 feet above the ground. To stow the hose, Mr. Dumas fed the hose with his left hand over the top of the side boards while holding the nozzle with his right hand...My glance turned to the gauges when I felt an extreme shock through the cyclic accompanied by a loud bang. The helicopter turned to the right as in a tail rotor failure, I immediately chopped the throttle...." According to the Flight Instructor's statement, after landing, he exited the helicopter to drive the fuel truck into position to refuel the helicopter while it was idling. He returned with the fuel truck and positioned it outside of the main rotor tip path plane. The flight instructor observed that the tip path plane had drifted down, and went to the RSP at the controls and told him to level the main rotor tip path plane. The flight instructor further stated: "...I refueled the helicopter and turned my back toward the helicopter, returning the fuel hose to the truck...The main rotor tip path plane must have been permitted to dip down by the pilot, low enough to hit the fuel hose as I carried it back to the truck, which in turn struck me and began the sequence of events that resulted in the...damage to the helicopter." In the Federal Aviation Administration (FAA) Inspector's report he stated that interviews with Plymouth Copters employees revealed that company policy mandates a minimum of a 10 foot clearance between the fuel truck and the turning rotor blades. With the helicopter centered on the helipad, the tip path plane clearance with the fuel truck was 3.44 feet. The FAA Inspector's report further stated: "...Robert Dumas is seventy four inches tall. The distance from the ground to the top of the side boards on the fuel trick is seventy one and a half inches. The optimum height of the main rotor disc is 111.66 inches...Under the best of conditions, the clearance available can be predicted at 30.16 inches. We re- enacted the stowage of the hose assembly using an employee of Plymouth Copters who is seventy four inches in height. Even under this controlled environment, the tendency was for the hose to deflect up from the top of the truck in excess of thirty inches...." ## Aircraft - Registration: [N7043J](https://openairdocs.org/deregistered/N7043J-2012-06-27), registration cancelled 2012-06-27, S/N 25020, built 1970 (OpenAirDocs) - Reported make and model: BELL 47G-5 - Registry model: [Bell 47G-5](https://openairdocs.org/model/bell-47g-5) (registry code 1181032) (OpenAirDocs) - Registry engine: [Lycoming VO-435 series](https://openairdocs.org/engine/lycoming-vo-435-series) (registry code 41525, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 25020 - Engines: LYCOMING VO-435-B1A 265 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Registered owner: Pac Leasing Corp - Airworthiness certificate: Standard, Normal - Airport: PYM, Plymouth ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; flight hours: 8,000 total, 8,000 as pilot in command, 80 in the last 90 days ## Weather - Conditions: Visual (VMC), Day - Wind: 320° at 7 knots - Visibility: 7 statute miles - Lowest ceiling: none - Temperature: 36 °F, dew point 9 °F - Altimeter: 30.00 inHg - Observed at: NZW, 16 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19940301003179A](https://openairdocs.org/incident/19940301003179A), Mar 1, 1994: Bell 47G5, Plymouth, MA, Substantial damage. During fueling with idling rotors the rotor blades drooped and struck instructor and fuel hose. ## Other investigations on N7043J (2) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB MKC73FCA30](https://openairdocs.org/ntsb/MKC73FCA30), Jun 24, 1973: Bell 47G-5 (N7043J), St Louis, MO, destroyed - [NTSB MKC71FCA27](https://openairdocs.org/ntsb/MKC71FCA27), Mar 20, 1971: Bell 47G5 (N7043J), Creve Coeur, MO, substantial damage From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- 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.