# NTSB ANC93FA056: Bell 204B, N204AQ, Copper Harbor, AK, May 2, 1993 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: May 2, 1993, 12:50 local (20:50 UTC) - Place: Copper Harbor, AK - Coordinates: 55.610378, -131.579406 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=55.6104&lon=-131.5794&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal, 1 minor; on the ground: 1 minor - Status: Completed, report December 2, 1994 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 2298 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC93FA056 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/2298/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=2298 - Page: https://openairdocs.org/ntsb/ANC93FA056 ## Probable cause FATIGUE FAILURE OF THE TAIL ROTOR GEARBOX, AND IMPROPER HELICOPTER OPERATIONS BEING CONDUCTED BY THE OPERATOR RESULTING IN REPETITIVE AT AND OVER MAXIMUM LOADS. FACTORS IN THE ACCIDENT WERE: MATERIAL DEFECT OF THE TAIL ROTOR GEAR BOX (INADEQUATE QUALITY CONTROL) BY THE COMPANY/OPERATOR, AND INADEQUATE SURVEILLANCE OF BOTH THE COMPANY OPERATIONS AND MAINTENANCE FACILITY BY THE FAA. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, hover - rotor drive system,tail rotor gearbox(90 deg) - fatigue (cause) - rotorcraft operations - excessive, company/operator management (cause) - inadequate surveillance of operation, faa(organization) (contributing factor) - rotor drive system,tail rotor gearbox(90 deg) - separation - In flight collision with terrain/water, descent - uncontrolled ## Analysis AEROLOGGING OPERATION REQUIRED A STEEP DESCENT FLIGHT PATH FROM THE LOG PICKUP SITE AT 1200 FT ELEVATION TO THE LANDING SITE AT 70 FT ELEVATION. DESCENT ESTIMATED TO TAKE 11-12 SECS, AND DESCRIBED AS 'STRAIGHT DOWN IN AUTOROTATION AND DROPPING THE LOGS.' PILOT EXPRESSED RESERVATIONS ABOUT 'BEING ABLE TO DO IT.' FOLLOWING A DESCENT, AND WHILE IN A HOVER, THE TAIL ROTOR & 90 DEG GEAR BOX SEPARATED. METALLURGICAL EXAM REVEALED FATIGUE SIGNATURES ON GEAR BOX CASE STUDS. GEAR BOX OF MILITARY ORIGIN. RECORDED WEIGHTS INDICATED THAT THE AIRCRAFT HAD BEEN OPERATING IN EXCESS OF THE GROSS WEIGHT HOOK LIMIT. THERE WAS NO RECORD OF SURVEILLANCE BY THE POI OR PMI FROM THE FAA OFFICE HOLDING THE OPERATOR'S CERTIFICATE. ## Factual narrative HISTORY OF FLIGHT On May 2, 1993, at approximately 1250 Alaska daylight time, a Bell 204B helicopter, N204AQ, collided with the ground during a precautionary landing at Copper Harbor, Alaska. The helicopter was operated by Chet Rasberry, Inc., d.b.a. CRI Helicopters, under 14 CFR Part 133, for aerologging business purposes. Operating in visual meteorological conditions on a company VFR flight plan, the helicopter had been engaged approximately 5 hours in aerologging at the site, 30 miles southwest of Ketchikan, Alaska. The commercial pilot, as sole occupant in the left pilot's seat, sustained fatal injuries and an employee of CRI on the ground received minor injuries. The helicopter was destroyed. Witnesses told investigators that the chief pilot, referred to as "Doc," had told the accident pilot, during the previous few days prior to the accident, to adopt a new flight path from the pickup site to the drop area, described as "straight down in an autorotation and dropping the logs." The NTSB and FAA investigators were told by the logging crew at Copper Harbor on May 3, 1993, the pilot had expressed reservations to logging camp employees about "being able to do it" (the new procedure) on the evening of May 1, 1993. In a statement provided investigators, a ground crewman whose job it was to hook logs to the helicopter's long line cable, estimated the new descent procedure to take "11 to 12 seconds to descend from me to the landing." He described the log pick up elevation to be approximately 1200 feet above sea level. Investigators estimated the log landing site and crash site to be at approximately the 70 foot elevation. Witnesses at the site told investigators that the helicopter had hoisted a log with its long line at the 1200 foot elevation when ground observers radioed that smoke was coming from the tail rotor. Following a descent and while in a 75 foot hover at the maintenance site, the tail rotor and 90 degree gear box reportedly separated with a "loud bang," followed by a loss of control, entering three rapid turns to the right and colliding with the ground. The maintenance mechanic said that the Bell 204B pilot had been hovering over the maintenance trailer and landing site, and "coiling the longline while descending in a hover straight down." He said "all of a sudden I saw the tail rotor come off and the helicopter started spinning, (and) I dove for cover under the trailer." Records indicated that the pilot had flown logging operations in the Bell 204B (N204AQ) between March 30, 1993 and April 18, 1993, followed by 10 days off at home in Washington state. Company representatives provided a schedule indicating that the pilot had returned to Ketchikan on April 31 and had resumed flight operations on Prince of Wales Island on May 1st. Since there was no April 31st on the calendar, witnesses recalled that the pilot had returned to Prince of Wales on the night before the accident. (May 1, 1993). INJURIES TO PERSONS The pilot in command, as sole occupant in the left seat of the helicopter received fatal injuries as a result of the crash. Witnesses at the scene of the accident told investigators that they did not remove the pilot from the helicopter for fear "of hurting his back." They said that they had no medical help for about one hour when the medical evacuation helicopter from Ketchikan arrived. The Ketchikan emergency medical service told investigators that the pilot had vital signs when they departed Copper Harbor, however the injured pilot lost vital signs during the medical evacuation, saying that he "coded en route" to the hospital. The mechanic employee received minor injuries when he fell or dove for cover upon seeing the tail rotor depart and the helicopter lose control while in a hover over the maintenance trailer. OTHER DAMAGE Investigators saw the side windows and windshields of a dump truck and a pickup truck shattered. Projectiles found on the insides of the vehicles consisted of golf ball size rocks and gravel. Investigators did not find aircraft parts to have struck those vehicles other than the frame damage on a boat trailer struck by the tail rotor. The tail rotor, attached to the 90 degree gear box struck the ground and an empty small boat trailer, 75 feet southeast of the helicopter impact point. The trailer received minor damage consisting of a 1/4 X 2 inch dent on its frame, and evidence was found that the tail rotor blades fractured at that point. PERSONNEL INFORMATION Captain Hugh R. Mackay Captain Mackay held a Commercial Pilot's certificate with ratings in airplane's single and multiengine land , rotorcraft helicopter pilot and instrument qualification in airplanes. He was employed as a pilot in command with CRI since January of 1993. Company records provided to the NTSB indicated that Captain Mackay completed a Bi-Annual Flight Review on January 27, 1993 and completed "initial, ground and flight phase of 133 only phase of the C. R. Inc. Pilot Training Program." The aircraft listed in that record was a Bell 204B. No curriculum or lesson plans were found reflecting this training program, nor were they required by federal regulation for companies of external load helicopters. The pilot provided a statement to AIG Aviation Insurance on January 4, 1993 which indicated that he was employed as a logging pilot by Northwest Helicopters, Inc., of Olympia, Washington. On that insurance application he reported having an estimated 7400 hours flight time in helicopters, 2000 hours of which were in the UH1B (Bell 204B). His application also stated that he had 1500 hours of "sling load" flight hours. In records provided by CRI, the company chief pilot certified the qualification of Captain Mackay to pilot "helicopters conducting Class B and Class C external loads." No records for flight training were found, nor were they required to be maintained by CRI. In a telephone interview with Captain Rick Leishman, chief logging pilot for CRI, the NTSB was told that Mr. Mackay was given "a check ride" at the time of employment and that he had been required to demonstrate emergency autorotations. The NTSB asked Captain Leishman if Mackay was required to demonstrate or was he trained in steep descents or autorotations with a load attached. He replied "no, I consider autorotations as an emergency (procedure) only." In records provided by the operator, Mr. Mackay had listed his initial airplane and helicopter training as from civilian instructors. His initial training in airplanes was in Cessna 150 and 172 airplanes in 1968 and helicopter training in Hiller 12E and Hughes 300 aircraft at the Olympia Flight Center in Washington State. The date of that training was not recorded in the information provided. AIRCRAFT INFORMATION The Bell model 204B helicopter, serial number 2198, helicopter was operating as a c ## Aircraft - Registration: [N204AQ](https://openairdocs.org/aircraft/N204AQ), registered now, S/N 2198 (OpenAirDocs) - Reported make and model: BELL 204B - Registry model: [Bell 204-B](https://openairdocs.org/model/bell-204-b) (registry code 1181404) (OpenAirDocs) - Registry engine: [Lycoming T-53 series](https://openairdocs.org/engine/lycoming-t-53-series) (registry code 41552, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 2198 - Airframe hours: 19420 - Engines: Lycoming T-53 1150 horsepower turbo shaft - Damage: Destroyed - Flight: Part 133 - Operator: Chester C. Rasberry, doing business as Cri Helicopters, Inc - Registered owner: Chet Rasberry Inc - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, April 25, 1993, 13 hours before - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: left; toxicology performed; flight hours: 8,500 total, 1,500 in this make and model, 8,400 as pilot in command, 17 in the last 90 days, 17 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 20° at 20 knots - Visibility: 10 statute miles - Lowest ceiling: 2,000 ft overcast - Temperature: 39 °F, dew point -0 °F ## 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 19930502011439A](https://openairdocs.org/incident/19930502011439A), May 2, 1993: Bell 204B, Copper Harbor, AK, Destroyed, 1 fatal. Smoke from tail rotor. Gear box broke during approach. Spun in. Over gross weight. Improper maintenance procedures. ## Docket (18 files) The files NTSB released with the investigation on June 3, 1995, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=2298. 3.1 MB in all. - Supplement A (item 1, .PDF, 186 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40000989&FileExtension=.PDF&FileName=Supplement%20A-Master.PDF - Supplement G (item 2, .PDF, 84 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40000990&FileExtension=.PDF&FileName=Supplement%20G-Master.PDF - Supplement I (item 3, .PDF, 71 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40000991&FileExtension=.PDF&FileName=Supplement%20I-Master.PDF - Witness Statements (item 4, .PDF, 165 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446371&FileExtension=.PDF&FileName=Witness%20Statements-Redacted.PDF - Interview Summary (item 5, .PDF, 87 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446372&FileExtension=.PDF&FileName=Interview%20Summary-Redacted.PDF - NTSB Metallurgist's Factual Report #93-108 (item 6, .PDF, 456 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446373&FileExtension=.PDF&FileName=NTSB%20Metallurgist%27s%20Factual%20Report%20%2393-108-Redacted.PDF - Handwritten Turn Weight Record, 5/2/93 (item 7, .PDF, 47 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40000994&FileExtension=.PDF&FileName=Handwritten%20Turn%20Weight%20Record,%205%2F2%2F93-Master.PDF - Copies of Gear Box Records (item 8, .PDF, 286 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446374&FileExtension=.PDF&FileName=Copies%20of%20Gear%20Box%20Records-Redacted.PDF - Supplementary Preliminary Information (item 9, .PDF, 126 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40000996&FileExtension=.PDF&FileName=Supplementary%20Preliminary%20Information-Master.PDF - FAA Letter dated 5/7/93 (item 10, .PDF, 625 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446375&FileExtension=.PDF&FileName=FAA%20Letter%20dated%205%2F7%2F93-Redacted.PDF - Bell Helicopter Letter dated 8/10/93 (item 11, .PDF, 103 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446376&FileExtension=.PDF&FileName=Bell%20Helicopter%20Letter%20dated%208%2F10%2F93-Redacted.PDF - Bell Helicopter Information Letter, 3/4/71 (item 12, .PDF, 44 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446377&FileExtension=.PDF&FileName=Bell%20Helicopter%20Information%20Letter,%203%2F4%2F71-Redacted.PDF - Bell Helicopter Model 204B Manual Exercpt (item 13, .PDF, 171 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40001000&FileExtension=.PDF&FileName=Bell%20Helicopter%20Model%20204B%20Manual%20Exercpt-Master.PDF - Excerpt Article from ROTORBREEZE, Jan/Feb 92 (item 14, .PDF, 324 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40001001&FileExtension=.PDF&FileName=Excerpt%20Article%20from%20ROTORBREEZE,%20Jan%2FFeb%2092-Master.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 15, .PDF, 110 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446378&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-Redacted.PDF - Toxicological Report (item 16, .PDF, 66 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40446380&FileExtension=.PDF&FileName=Toxicological%20Report-Redacted.PDF - Photo 1. Wreckage showing cockpit left front side, noting impact dynamics and deformation. (item 17, .PDF, 61 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40001004&FileExtension=.PDF&FileName=Photo%201.%20%20Wreckage%20showing%20cockpit%20left%20front%20side,%20noting%20impact%20dynamics%20and%20deformation.-Master.PDF - Photo 2. Cockpit from right side. (item 18, .PDF, 48 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40001005&FileExtension=.PDF&FileName=Photo%202.%20%20Cockpit%20from%20right%20side.-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.