20180111000739A

Accident · No damage

FAA accident report · Hughes 369D · Naguabo, PR · January 11, 2018

Date
January 11, 2018 · 13:55 local
Place
Naguabo, PR
Airport
Luis Munoz Marin International
Phase of flight
Other, Specify
Operating rules
Rotorcraft external load (Part 133)
Operator
4HLL
Damage
No damage
Aircraft
N571HH
NTSB investigation
NTSBERA18LA091
Reported as
Hughes 369D
People aboard
1
Fatal injuries
0
Other injuries
1
Pilot’s certificates
Commercial pilot, flight instructor

From the FAA’s Accident/Incident Data System (AIDS), through its Aviation Safety Information Portal, as reported. The NTSB investigates accidents separately, and its record of an accident is the fuller one. The aircraft is matched to the registry by N-number and event date, checked against the reported make and model; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

What happened

The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.

The pilot in command (PIC) worked for high line helicopters, LLC (operator), and the linemen worked for arc American, inc (arc), an Indiana based power line restoration company. The mission for that day was to install insulators and pick up wire to the linemen to pin in its place. There were two linemen working together on this mission: Mr. Cprivacy data omitted (who fell), and his co-worker, lineman privacy data omitted. Both linemen worked on a 16-FT. Ladder while on the electric tower; coming on/off the electric tower on to the ladder and vice versa, as needed to work on various arms. It was human external cargo "(hec)" operation that involved moving personnel on/with 16-foot ladder to/from/ on and around the electric towers.

On the day of this occurrence, the helicopter moved the ladder with the lineman on it several times throughout the day; and used the a-frame for "hec" operation, and used the grapple for equipment, cargo, cable. (The videos recorded by a nearby witness showed that the helicopter was using green color a-frame while moving the ladder with the lineman, and using the grapple (dark red color) while lifting the electrical cable to the tower?s arms).

At the time of this occurrence, instead of an a-frame, a grapple was used in the process with the lineman on it.

Pilot stated that he received a radio transmission for a ladder pick; and he moved into position to pick up the ladder; and he made visual contact with two linemen: one near the bottom and the other one at the top arm of the electric tower. According to the pilot, he was to pick up the ladder only. However, both linemen stated that every time the ladder was moved, a lineman moved with the ladder at all of the previous times. According to the pilot, during the ladder pick, pilot felt that the ladder was still bound to the structure, and observed the two linemen shaking the ladder in an attempt to free it.

In contrast, the lineman stated that he was not ready for the pull yet but the pilot was pulling already. At this time, the lineman privacy data omitted reached out to remove the safety chain off the ladder. As a result, at this point in time, the lineman remained connected to the ladder, and the ladder remained connected to the long line of the helicopter via grapple. The ground witness observed that the pilot reversed the pull, and began descending slowly. The second lineman privacy data omitted observed that the bottom of the ladder contacted the arm of the tower, and stopped the further descent of the ladder. Ground witness stated that the semi circular hooks on the top of the ladder did not engage properly on to the tower?s arm, rather the open ends of the hooks remained rested on the arm while the helicopter was descending, and this caused the grapple to come loose off of the ladder due to countinuing descent of the helicopter. At some point during this descent, the ladder pivoted, and snapped off of the grapple, and lineman privacy data omitted and the ladder fell approximately 80 feet to the ground. The lineman was evacuated to the nearby hospital and seriously injured as a result of this fall.

As the FAA filed it

THE PILOT IN COMMAND (PIC) WORKED FOR HIGH LINE HELICOPTERS, LLC (OPERATOR), AND THE LINEMEN WORKED FOR ARC AMERICAN, INC (ARC), AN INDIANA BASED POWER LINE RESTORATION COMPANY. THE MISSION FOR THAT DAY WAS TO INSTALL INSULATORS AND PICK UP WIRE TO THE LINEMEN TO PIN IN ITS PLACE. THERE WERE TWO LINEMEN WORKING TOGETHER ON THIS MISSION: MR. C^PRIVACY DATA OMITTED^ (WHO FELL), AND HIS CO-WORKER, LINEMAN ^PRIVACY DATA OMITTED^. BOTH LINEMEN WORKED ON A 16-FT. LADDER WHILE ON THE ELECTRIC TOWER; COMING ON/OFF THE ELECTRIC TOWER ON TO THE LADDER AND VICE VERSA, AS NEEDED TO WORK ON VARIOUS ARMS. IT WAS HUMAN EXTERNAL CARGO "(HEC)" OPERATION THAT INVOLVED MOVING PERSONNEL ON/WITH 16-FOOT LADDER TO/FROM/ ON AND AROUND THE ELECTRIC TOWERS.

ON THE DAY OF THIS OCCURRENCE, THE HELICOPTER MOVED THE LADDER WITH THE LINEMAN ON IT SEVERAL TIMES THROUGHOUT THE DAY; AND USED THE A-FRAME FOR "HEC" OPERATION, AND USED THE GRAPPLE FOR EQUIPMENT, CARGO, CABLE. (THE VIDEOS RECORDED BY A NEARBY WITNESS SHOWED THAT THE HELICOPTER WAS USING GREEN COLOR A-FRAME WHILE MOVING THE LADDER WITH THE LINEMAN, AND USING THE GRAPPLE (DARK RED COLOR) WHILE LIFTING THE ELECTRICAL CABLE TO THE TOWER?S ARMS).

AT THE TIME OF THIS OCCURRENCE, INSTEAD OF AN A-FRAME, A GRAPPLE WAS USED IN THE PROCESS WITH THE LINEMAN ON IT.

PILOT STATED THAT HE RECEIVED A RADIO TRANSMISSION FOR A LADDER PICK; AND HE MOVED INTO POSITION TO PICK UP THE LADDER; AND HE MADE VISUAL CONTACT WITH TWO LINEMEN: ONE NEAR THE BOTTOM AND THE OTHER ONE AT THE TOP ARM OF THE ELECTRIC TOWER. ACCORDING TO THE PILOT, HE WAS TO PICK UP THE LADDER ONLY. HOWEVER, BOTH LINEMEN STATED THAT EVERY TIME THE LADDER WAS MOVED, A LINEMAN MOVED WITH THE LADDER AT ALL OF THE PREVIOUS TIMES. ACCORDING TO THE PILOT, DURING THE LADDER PICK, PILOT FELT THAT THE LADDER WAS STILL BOUND TO THE STRUCTURE, AND OBSERVED THE TWO LINEMEN SHAKING THE LADDER IN AN ATTEMPT TO FREE IT.

IN CONTRAST, THE LINEMAN STATED THAT HE WAS NOT READY FOR THE PULL YET BUT THE PILOT WAS PULLING ALREADY. AT THIS TIME, THE LINEMAN ^PRIVACY DATA OMITTED^ REACHED OUT TO REMOVE THE SAFETY CHAIN OFF THE LADDER. AS A RESULT, AT THIS POINT IN TIME, THE LINEMAN REMAINED CONNECTED TO THE LADDER, AND THE LADDER REMAINED CONNECTED TO THE LONG LINE OF THE HELICOPTER VIA GRAPPLE. THE GROUND WITNESS OBSERVED THAT THE PILOT REVERSED THE PULL, AND BEGAN DESCENDING SLOWLY. THE SECOND LINEMAN ^PRIVACY DATA OMITTED^ OBSERVED THAT THE BOTTOM OF THE LADDER CONTACTED THE ARM OF THE TOWER, AND STOPPED THE FURTHER DESCENT OF THE LADDER. GROUND WITNESS STATED THAT THE SEMI CIRCULAR HOOKS ON THE TOP OF THE LADDER DID NOT ENGAGE PROPERLY ON TO THE TOWER?S ARM, RATHER THE OPEN ENDS OF THE HOOKS REMAINED RESTED ON THE ARM WHILE THE HELICOPTER WAS DESCENDING, AND THIS CAUSED THE GRAPPLE TO COME LOOSE OFF OF THE LADDER DUE TO COUNTINUING DESCENT OF THE HELICOPTER. AT SOME POINT DURING THIS DESCENT, THE LADDER PIVOTED, AND SNAPPED OFF OF THE GRAPPLE, AND LINEMAN ^PRIVACY DATA OMITTED^ AND THE LADDER FELL APPROXIMATELY 80 FEET TO THE GROUND. THE LINEMAN WAS EVACUATED TO THE NEARBY HOSPITAL AND SERIOUSLY INJURED AS A RESULT OF THIS FALL.

NTSB investigation

The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.