# NTSB ANC02LA053: de Havilland DHC-6-300, N353PM, Ketchikan, AK, June 20, 2002 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: June 19, 2002, 17:00 local (Jun 20, 2002, 01:00 UTC) - Place: Ketchikan, AK - Coordinates: 55.349998, -131.676666 - Nearby events: https://openairdocs.org/map.md?lat=55.3500&lon=-131.6767&mi=10 - Phase of flight: [Taxi](https://openairdocs.org/ntsb-phases/250) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 31 uninjured - Status: Completed, report January 16, 2003 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: Federal Aviation Administration - NTSB case key (mKey): 54996 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC02LA053 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/54996/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=54996 - Page: https://openairdocs.org/ntsb/ANC02LA053 ## Probable cause (aircraft 2) The failure of a ground handler to follow company proceedure/directives, and his premature release of a mooring line. Factors associated with the accident were the congested operations area, and the operator's failure to provide adequate safe zones for the airplanes. ## Probable cause (aircraft 1) The failure of a ground handler to follow company procedures/directives, and his premature release of a mooring line. Factors associated with the accident were the congested operations area, and the operator's failure to provide adequate safe zones for the airplanes. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Collision between aircraft (other than midair), taxi - procedures/directives - not followed, ground personnel (cause) - facility inadequate, company/operator management (contributing factor) - airport/facilities - congested (contributing factor) - tie down - removed, ground personnel (cause) - Collision between aircraft (other than midair), standing - engine(s) not operating - procedures/directives - not followed, ground personnel (cause) - airport/facilities - congested (contributing factor) - tie down - removed, ground personnel (cause) - facility inadequate, company/operator management (contributing factor) ## Analysis (aircraft 2) A float-equipped deHavilland DHC-6, N235SA, was moored at a dock. The passengers were boarded, and the two pilots were finishing preflight duties. The airplane's engines were not running. Moored at the same dock, about four feet behind N235SA, was another float-equipped deHavilland DHC-6, N353PM. Both airplanes were being operated as sightseeing flights. The pilots of N353PM had completed their pretaxi checks, and the engines were running. The pilot in command of N353PM signaled the dockhand to disconnect the shore power. The dockhand disconnected the shore power, and without direction to do so, let go the mooring ropes. N353PM, under idle power, surged forward into the tail of N235SA. Both airplanes received substantial damage. Company procedures at the time of the accident directed the dockhand to wait for a signal from the pilot before letting go the mooring ropes. Post-accident the operation has been moved to a longer dock, to provide greater distance between airplanes. The procedure has been changed, and the first officer is now responsible for releasing the mooring ropes at the direction of the pilot. ## Analysis (aircraft 1) A float-equipped deHavilland DHC-6, N235SA, was moored at a dock. The passengers were boarded, and the two pilots were finishing preflight duties. The airplane's engines were not running. Moored at the same dock, about four feet behind N235SA, was another float-equipped deHavilland DHC-6, N353PM. Both airplanes were being operated as sightseeing flights. The pilots of N353PM had completed their pretaxi checks, and the engines were running. The pilot in command of N353PM signaled the dockhand to disconnect the shore power. The dockhand disconnected the shore power, and without direction to do so, let go the mooring ropes. N353PM, under idle power, surged forward into the tail of N235SA. Both airplanes received substantial damage. Company procedures at the time of the accident directed the dockhand to wait for a signal from the pilot before letting go the mooring ropes. Post-accident the operation has been moved to a longer dock, to provide greater distance between airplanes. The procedure has been changed, and the first officer is now responsible for releasing the mooring ropes at the direction of the pilot. ## Factual narrative (aircraft 2) On June 19, 2002, about 1700 Alaska daylight time, a float-equipped deHavilland DHC-6-300 airplane, N353PM, sustained substantial damage while water taxiing at Ketchikan, Alaska, when it struck another float-equipped deHavilland DHC-6-300, N235SA, which also sustained substantial damage. N235SA was moored to the dock when the accident occurred. Both airplanes were being operated as visual flight rules (VFR) local area sightseeing flights under Title 14, CFR Part 135, by PROMECH INC., dba, Seaborne Seaplane Adventures, of Ketchikan. The captain, the first officer, and the 15 passengers on N353PM, were not injured. The captain, the first officer, and the 12 passengers on N235SA, were not injured. Visual meteorological conditions prevailed, and VFR company flight following procedures were in effect. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on June 20, 2002, the captain of N353PM said he was preparing the airplane for departure when the accident occurred. The airplane doors were closed, passengers seated, and engines running at idle power. The airplane was still tied to the dock, and the shore power cable was attached. The captain said he gave the appropriate hand signal to the dockhand to disconnect the shore power cable. He said after disconnecting the shore power cable, the dockhand released the mooring rope holding the airplane to the dock. The captain said an additional hand signal is used to signal the dockhand to release the mooring line, and that signal was not given. The airplane, N353PM, surged forward under idle power, and its nose collided with the tail of N235SA, which was moored to the dock about four feet in front of N353PM. The captain of N353PM said he was able to shut down the engines before the two airplanes made contact, but the propellers were still wind-milling during the collision. N353PM sustained substantial damage to its propeller blades and nose. N235SA sustained substantial damage to its elevators and vertical stabilizer. During a conversation with the IIC, the director of operations for the operator said the captain and first officer of N235SA had just finished loading passengers, and were standing on the dock at the time of the accident. N235SA was moored to the dock, and the engines were not running. He said after the accident, the floatplane operation has been moved to another dock where the airplanes are separated by at least 50 feet. He said the operations manual/procedures have been revised, and dockhands no longer handle departing airplanes. Under the new procedure the captain (PIC) is at the airplane's controls, and the first officer releases the mooring lines. ## Factual narrative (aircraft 1) On June 19, 2002, about 1700 Alaska daylight time, a float-equipped deHavilland DHC-6-300 airplane, N353PM, sustained substantial damage while water taxiing at Ketchikan, Alaska, when it struck another float-equipped deHavilland DHC-6-300, N235SA, which also sustained substantial damage. N235SA was moored to the dock when the accident occurred. Both airplanes were being operated as visual flight rules (VFR) local area sightseeing flights under Title 14, CFR Part 135, by PROMECH INC., dba, Seaborne Seaplane Adventures, of Ketchikan. The captain, the first officer, and the 15 passengers on N353PM, were not injured. The captain, the first officer, and the 12 passengers on N235SA, were not injured. Visual meteorological conditions prevailed, and VFR company flight following procedures were in effect. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on June 20, 2002, the captain of N353PM said he was preparing the airplane for departure when the accident occurred. The airplane doors were closed, passengers seated, and engines running at idle power. The airplane was still tied to the dock, and the shore power cable was attached. The captain said he gave the appropriate hand signal to the dockhand to disconnect the shore power cable. He said after disconnecting the shore power cable, the dockhand released the mooring rope holding the airplane to the dock. The captain said an additional hand signal is used to signal the dockhand to release the mooring line, and that signal was not given. The airplane, N353PM, surged forward under idle power, and its nose collided with the tail of N235SA, which was moored to the dock about four feet in front of N353PM. The captain of N353PM said he was able to shut down the engines before the two airplanes made contact, but the propellers were still wind-milling during the collision. N353PM sustained substantial damage to its propeller blades and nose. N235SA sustained substantial damage to its elevators and vertical stabilizer. During a conversation with the IIC, the director of operations for the operator said the captain and first officer of N235SA had just finished loading passengers, and were standing on the dock at the time of the accident. N235SA was moored to the dock, and the engines were not running. He said, after the accident, the floatplane operation has been moved to another dock where the airplanes are separated by at least 50 feet. He said the operations manual/procedures have been revised, and dockhands no longer handle departing airplanes. Under the new procedure, the captain (PIC) is at the airplane's controls, and the first officer releases the mooring lines. ## Aircraft 1 - Registration: [N353PM](https://openairdocs.org/deregistered/N353PM-2006-05-25), registration cancelled 2006-05-25, S/N 351, built 1973 (OpenAirDocs) - Reported make and model: de Havilland DHC-6-300 - Registry model: [Dehavilland DHC-6-300](https://openairdocs.org/model/dehavilland-dhc-6-300) (registry code 2802630) (OpenAirDocs) - Registry engine: [Pratt & Whitney PT6A series](https://openairdocs.org/engine/pratt-whitney-pt6a-series) (registry code 52032, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: 351 - Airframe hours: 13701.1 - Engines: Pratt & Whitney PT6A-27 680 horsepower turbo prop - Damage: Substantial damage - Flight: Part 135 - Operator: Promech Inc., doing business as Seaborne Seaplane Adventures - Registered owner: N353pm, LLC - Airworthiness certificate: Standard, Normal - Last inspection: Continuous airworthiness, September 11, 2001, 95.6 hours before - Departed: Ketchikan, AK - Destination: Ketchikan, AK - Flight plan: Company VFR - Airport: WFB, Ketchikan Water Front ## Aircraft 2 - Registration: N235SA (not matched to a registry record) - Reported make and model: de Havilland DHC-6-300 - Category: Airplane - Serial number: 771 - Airframe hours: 25732 - Engines: Pratt & Whitney PT-6A-27 680 horsepower turbo prop - Damage: Substantial damage - Flight: Part 135 - Operator: Promech Inc., doing business as Seaborne Seaplane Adventures - Registered owner: Kevin M. Hack - Airworthiness certificate: Standard, Normal - Last inspection: Continuous airworthiness, May 23, 2002, 106 hours before - Flight plan: Company VFR - Airport: WFB, Ketchikan Water Front ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot, aircraft N353PM; age 36; injuries: none; commercial, airline transport; airplane ratings: single-engine sea, multi-engine land, single-engine land, multi-engine sea; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; last flight review May 16, 2002; seat: left; flight hours: 11,523 total, 1,042 in this make and model, 11,323 as pilot in command, 95 in the last 90 days, 3 in the last 30 days - Co-pilot, aircraft N353PM; injuries: none; medical: class 2, valid medical--no waivers/lim. - Pilot, aircraft N235SA; age 39; injuries: none; airline transport; airplane ratings: multi-engine sea, single-engine sea, multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; last flight review February 19, 2002; seat: left; flight hours: 12,900 total, 880 in this make and model, 12,586 as pilot in command, 250 in the last 90 days, 170 in the last 30 days, 7 in the last 24 hours - Co-pilot, aircraft N235SA; age 32; injuries: none; commercial; airplane ratings: multi-engine land, multi-engine sea, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; last flight review May 11, 2002; seat: right; flight hours: 7,300 total, 230 in this make and model, 6,800 as pilot in command, 246 in the last 90 days, 70 in the last 30 days, 6 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 120° at 7 knots - Visibility: 10 statute miles - Lowest ceiling: 4,400 ft overcast - Temperature: 55 °F, dew point 46 °F - Altimeter: 30.19 inHg - Observed at: PAKT, 1 nm away ## FAA reports on this event (2) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20020619016809A](https://openairdocs.org/incident/20020619016809A), Jun 19, 2002: Dhav DHC6300, Ketchikan, AK, No damage. (-23) N353PM was tied to the dock behind N235SA. Both aircraft were loaded with passengers, preparing for a flightseeing tour. N353PM'S engines were running.… - [Accident 20020619020449A](https://openairdocs.org/incident/20020619020449A), Jun 19, 2002: Dhav DHC6300, Ketchikan, AK, No damage. (-23) N235SA was tied to the dock, with 15 passengers on board, preparing to start engines when it was struck from behind by N353PM. N353PM had been… ## Docket (2 files) The files NTSB released with the investigation on November 11, 2002, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=54996. 978 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1, N353PM (item 1, .PDF, 520 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40447721&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1,%20N353PM-Master.PDF - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1, N235SA (item 2, .PDF, 459 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40447722&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1,%20N235SA-Master.PDF 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.