# NTSB LAX95GA264: Mcdonnell Douglas 369D, N1090S, Hauula, HI, July 21, 1995 - Type: NTSB accident investigation - Classification: Accident · Fatal · Final report - Date: July 21, 1995, 12:27 local (22:27 UTC) - Place: Hauula, HI - Coordinates: 21.589639, -157.920211 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=21.5896&lon=-157.9202&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 3 fatal - Status: Completed, report February 27, 1996 - Report: Approved by Office Director - NTSB case key (mKey): 28946 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX95GA264 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/28946/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=28946 - Page: https://openairdocs.org/ntsb/LAX95GA264 ## Probable cause the pilot's poor judgement by intentionally flying into adverse weather conditions in mountainous terrain with an external load and no observer which resulted in loss of aircraft control. Factors were pressure from the conditions/events and a lack of total experience in the type of operation. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, maneuvering - terrain condition - mountainous/hilly (contributing factor) - weather condition - clouds (contributing factor) - weather condition - turbulence,terrain induced (contributing factor) - flight into known adverse weather - intentional, pilot in command (cause) - judgment - poor, pilot in command (cause) - pressure induced by conditions/events (contributing factor) - lack of total experience in type operation, pilot in command (contributing factor) - Loss of control - in flight, maneuvering - aircraft control - not maintained, pilot in command (cause) - external load cable/hook - entangled - Airframe/component/system failure/malfunction, descent - uncontrolled - rotorcraft flight control,pitch change rod/link - overload - aircraft control - not possible - In flight collision with terrain/water, descent - uncontrolled ## Analysis THE FIRE DEPARTMENT HELICOPTER PILOT WAS FLYING WITHOUT AN OBSERVER. HE WAS INSERTING TWO POLICE OFFICERS WHO WERE IN A RESCUE NET 50 FEET BELOW THE HELICOPTER, INTO MOUNTAINOUS TERRAIN TO SEARCH FOR A MISSING HIKER. DETERIORATING WEATHER AND CLOUD COVER WITH TURBULENCE WAS PRESENT. GROUND PERSONNEL WARNED THE PILOT THREE TIMES OF THE DETERIORATING CONDITIONS. A WITNESS STATED THAT THE HELICOPTER WAS PARTIALLY IN THE CLOUDS BUT THE NET WAS IN THE CLEAR. HIKERS IN A CANYON NEAR THE ACCIDENT SITE OBSERVED THE NET SWINGING LIKE A PENDULUM THROUGH AN ARC OF 45 TO 50 DEGREES. EXAMINATION OF THE WRECKAGE REVEALED THAT THE LINE WHICH SECURED THE NET TO THE HELICOPTER BECAME ENTANGLED WITH THE MAIN ROTOR AND WAS FOUND WRAPPED AROUND THE MAIN ROTOR MAST AND ALL THE MAIN ROTOR PITCH CHANGE LINKS WERE FACTURED. THE HELICOPTER PILOT'S FIRE DEPARTMENT RECORDS INDICATED HE HAD 511 HOURS OF HELICOPTER TIME WITH 2500 HOURS OF FIXED WING TIME. RECORDS WERE RECOVERED TO DOCUMENT ABOUT 261 HOURS OF ACTUAL HELICOPTER TIME. THE PILOT HAD RECEIVED ABOUT 50 HOURS OF DUAL INSTRUCTION FROM THE FIRE DEPARTMENT CHIEF PILOT IN THEIR TYPE OF OPERATIONS. ## Factual narrative HISTORY OF FLIGHT On July 21, 1995, about 1227 hours Hawaiian standard time, a McDonnell Douglas 369D, N1090S, operating under call sign Air 1 by the Honolulu Fire Department (HFD) as a public use aircraft, was destroyed while maneuvering near Hauula, on the island of Oahu, Hawaii. Changing meteorological conditions existed during this time. The pilot and two passengers, who were suspended beneath the helicopter in a rescue net, received fatal injuries. The flight originated on the day of the accident as an on-going search for a lost hiker in the Koolau Mountains near Sacred Falls. The pilot had made two prior insertions of search and rescue (SAR) personnel into the general area of the search. They repelled out of the helicopter to the ground. On each of the two insertions an observer was onboard to retrieve the rope. The first two inserted SAR personnel were subsequently relocated separately by the pilot with an observer onboard to a campsite with the use of a Billy Pugh helicopter rescue net. According to an HFD report to the Safety Board, after returning to the staging area, a decision was made to insert two Honolulu Police Department (HPD) officers into the search area at one time using the Billy Pugh net. The report stated that the decision was made by the pilot to fly without an observer. According to an HFD pilot, when operating without an observer the pilot must lean outside of the helicopter to maintain visual contact with the net. According to resident search personnel, changing trade winds and cloud cover are a common phenomena in the area and had been affecting the search for 5 days. After the pilot departed the staging area with the two HPD searchers in the net, a previously placed searcher radioed the pilot of Air 1 three times. He advised the pilot, "Pete, it's just too soupy up here, your gonna have to take em back down. I cant even see the other side of the river." A review of the recorded voice communications revealed that there was no verbal acknowledgment from the pilot. Shortly thereafter, a searcher heard a crash or impact sound followed briefly by a sound of the helicopter engine noise spooling up then down and then silence. Two people were hiking together in the Sacred Falls area at the time of the accident. They were both interviewed by telephone. Both hikers observed the helicopter in-flight with the net attached; however, they could not positively identify what was in the net. The time frame of between 1225 and 1230 was established by their need to start hiking back out of the canyon by a certain time. The first hiker to be interviewed stated that she observed the helicopter turning slowly and descending with the net swinging back and forth like a pendulum. She estimated the amount of swing to be about 20 to 30 degrees. She also noted that the helicopter was close to the mountainous terrain and the weather was cloudy with intermittent light rain. The second hiker also observed the helicopter turning slowly, but noted that the helicopter was partially in the clouds which were boiling around the helicopter. He stated that the net was in the clear, but swinging back and forth an estimated 45 to 50 degrees like a pendulum. He also noted that the helicopter appeared to be close to the mountainous terrain. PERSONNEL INFORMATION The pilot was employed by the HFD on March 1, 1991, as a fire fighter. On October 13, 1994, the pilot met all the qualifications for flying as a relief pilot. The pilot was selected for relief pilot training on January 13, 1994. The HFD does not have a relief pilot position. Once the firefighter is qualified to be a relief pilot, he continues in his regular position as a firefighter and is temporarily assigned to a pilot's position in the event of an absence of the regular pilot. At the time of the request, he reported a total of 1,990 fixed wing hours and 321 helicopter hours, for a combined total flight time of 2,311 hours. Examination of all available records disclosed differences in the pilot's flight experience as entered in the various documents. The pilot reported a total flight time of 3,400 hours with 200 in the last 6 months on his last class two flight physical, dated June 8, 1995. According to helicopter flight school records, the pilot started helicopter flight training on September 11, 1992, at Burbank, California. The operator provided a Bell 47-D1, with a flight instructor. According to the operator and flight instructor records, the pilot flew from September 11, 1992, through October 9, 1992, during which time he received his private, commercial, and CFI add-on ratings. The instructor stated that he flew 34.8 hours of dual flight instruction with the pilot. The instructor also stated that the pilot flew an additional 17 hours of solo while preparing for his add-on ratings. The pilot's last add-on rating was for flight instructor rotorcraft helicopter on October 9, 1992. At that time, he reported 57 total helicopter flight hours, with 22 hours of dual instruction and 38 hours of solo flight. The pilot's log book documents 22.8 hours of dual and 39.4 hours of solo flight in the Bell 47-D1 helicopter. According to the pilot's log book, on February 13, 1993, the pilot took his first dual flight instruction in an HFD helicopter. According to HFD records, at the time of the accident the pilot had accumulated a total of 222.2 hours in the HFD helicopter; 50.3 of these hours were dual instruction. The last documented dual instruction was October 13, 1994, and consisted of his relief pilot checkout flight and a biennial flight review. According to a pilot history form provided by the pilot to HFD, as of June 20, 1995, the pilot reported 3,011 total flight hours. Of that, 511 hours were helicopter flight hours with about 200 hours in a MD369D. In the last 90 days he listed 3 hours of MD369D helicopter flight time. A review of the pilot's actual flight logs revealed that they were sporadically dated with incomplete entries and no page totals. An interview was conducted with the HFD chief pilot. The chief pilot stated that their were no written training records, written examinations, or dual flight instruction formats given the accident pilot. An examination of the mission log book revealed that the accident pilot responded to about 33 alarms as a solo pilot. During the 33 alarms, the pilot performed about 10 rescues, with about nine water or net operations, and three repellings. The chief pilot was asked if their was any evidence of an emergency briefing of the HPD net passengers prior to the last flight. He stated that there was no briefing. He was then asked if there would have routinely been a briefing of passengers prior to flight. He stated no because they routinely work with their own personnel who are trained by the HFD. AIRCRAFT INFORMATION The accident helicopter was operating as Air 1. To differentiate between the two helicopters on the ground for maintenance purposes or general reference, the accident helicopter was actually known as Air 2. Whichever helicopter was airborne, for communication purposes, the helicopter was called Air 1. If the second helicopter was called out at the same time, it was called Air 2. The McDonnell Douglas 369D helicopter was manufactured as a 1980 model. According to the maintenance records, at the time of the accident the helicopter had accumulated 6,592.6 hours of operation. The helicopter was maintained under a maintenance program provided by the manufacturer, McDonnell Douglas, as a 100, 200, and 300-hour inspection program. A review of the records revealed no outstanding maintenance items. During conversations with the accident pilot's wife, she stated that her husband had told her that both helicopters had vibrations. She stated that Air 2 had an overtemp problem some time around July 1, 1995. She stated that her husb ## Aircraft - Registration: [N1090S](https://openairdocs.org/deregistered/N1090S-1996-03-02), registration cancelled 1996-03-02, S/N 800788D (OpenAirDocs) - Reported make and model: MCDONNELL DOUGLAS 369D - Registry model: [Hughes Helicopters HUGHES 369D](https://openairdocs.org/model/hughes-helicopters-hughes-369d) (registry code 4470706) (OpenAirDocs) - Category: Helicopter - Serial number: 800788D - Airframe hours: 6592 - Engines: ALLISON 250-C20B 450 horsepower turbo shaft - Damage: Destroyed - Fire: On-Ground - Flight: Public aircraft, Part 91 - Registered owner: City/County Of Honolulu - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, April 18, 1995, 92 hours before - Departed: NONE, HI ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 39; 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: 3,400 total ## Weather - Conditions: Instrument (IMC), Day - Wind: 45° at 20 knots, gusting 25 - Visibility: 0.4 statute miles ## 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 19950721046659A](https://openairdocs.org/incident/19950721046659A), Jul 21, 1995: Hughes 369D, Hauula Oahu, HI, Destroyed, 3 fatal. Hfd search sling load with 2 crew. Turbulence swinging load. Rope hit rotors. Wrapped around mast. Lost control. ## Docket (55 files) The files NTSB released with the investigation on February 12, 1996, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=28946. 39.2 MB in all. - Supplement A (item 1, .PDF, 185 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041010&FileExtension=.PDF&FileName=Supplement%20A-Master.PDF - Supplement B (item 2, .PDF, 280 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041011&FileExtension=.PDF&FileName=Supplement%20B-Master.PDF - Supplement G (item 3, .PDF, 84 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041012&FileExtension=.PDF&FileName=Supplement%20G-Master.PDF - Supplement K (item 4, .PDF, 320 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041013&FileExtension=.PDF&FileName=Supplement%20K-Master.PDF - Supplement S (item 5, .PDF, 45 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041014&FileExtension=.PDF&FileName=Supplement%20S-Master.PDF - Witness Statements (item 6, .PDF, 212 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40413398&FileExtension=.PDF&FileName=Witness%20Statements-Redacted.PDF - Maps or Charts of Accident Area (item 7, .PDF, 240 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40188506&FileExtension=.PDF&FileName=Maps%20or%20Charts%20of%20Accident%20Area-Master.PDF - McDonnell Douglas Rotor Blade Attaching Pin Information (item 8, .PDF, 977 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40413399&FileExtension=.PDF&FileName=McDonnell%20Douglas%20Rotor%20Blade%20Attaching%20Pin%20Information-Redacted.PDF - Allison Engine Over Temperature Information (item 9, .PDF, 914 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40413400&FileExtension=.PDF&FileName=Allison%20Engine%20Over%20Temperature%20Information-Redacted.PDF - McDonnell Douglas Helicopter Report (item 10, .PDF, 353 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40413401&FileExtension=.PDF&FileName=McDonnell%20Douglas%20Helicopter%20Report-Redacted.PDF - Honolulu Fire Department Helicopter Operations (item 11, .PDF, 789 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041019&FileExtension=.PDF&FileName=Honolulu%20Fire%20Department%20Helicopter%20Operations-Master.PDF - Allison Engine Company Report (item 12, .PDF, 28.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40413402&FileExtension=.PDF&FileName=Allison%20Engine%20Company%20Report-Redacted.PDF - Allison Photo 5. The general location of the site. (item 13, .PDF, 27 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041021&FileExtension=.PDF&FileName=Allison%20Photo%205.%20%20The%20general%20location%20of%20the%20site.-Master.PDF - Allison Photo 8. Main impact site. (item 14, .PDF, 57 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041022&FileExtension=.PDF&FileName=Allison%20Photo%208.%20%20Main%20impact%20site.-Master.PDF - Allison Photo 11. Main impact site. (item 15, .PDF, 88 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041023&FileExtension=.PDF&FileName=Allison%20Photo%2011.%20%20Main%20impact%20site.-Master.PDF - Allison Photo 16. Tail rotor. (item 16, .PDF, 59 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041024&FileExtension=.PDF&FileName=Allison%20Photo%2016.%20%20Tail%20rotor.-Master.PDF - Allison Photo 19. Main fuselage. (item 17, .PDF, 64 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041025&FileExtension=.PDF&FileName=Allison%20Photo%2019.%20%20Main%20fuselage.-Master.PDF - Allison Photo 31. Recovery of the wreckage. (item 18, .PDF, 36 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041026&FileExtension=.PDF&FileName=Allison%20Photo%2031.%20%20Recovery%20of%20the%20wreckage.-Master.PDF - Allison Photo 67. Main rotor blades. (item 19, .PDF, 42 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041027&FileExtension=.PDF&FileName=Allison%20Photo%2067.%20%20Main%20rotor%20blades.-Master.PDF - Allison Photo 68. Main rotor blades. (item 20, .PDF, 62 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041028&FileExtension=.PDF&FileName=Allison%20Photo%2068.%20%20Main%20rotor%20blades.-Master.PDF - Allison Photo 73. Main rotor blade. (item 21, .PDF, 58 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041029&FileExtension=.PDF&FileName=Allison%20Photo%2073.%20%20Main%20rotor%20blade.-Master.PDF - Allison Photo 74. Main rotor blade. (item 22, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041030&FileExtension=.PDF&FileName=Allison%20Photo%2074.%20%20Main%20rotor%20blade.-Master.PDF - Allison Photo 77. Main rotor blade. (item 23, .PDF, 67 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041031&FileExtension=.PDF&FileName=Allison%20Photo%2077.%20%20Main%20rotor%20blade.-Master.PDF - Allison Photo 87. Transmission & rotor head. (item 24, .PDF, 52 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041032&FileExtension=.PDF&FileName=Allison%20Photo%2087.%20%20Transmission%20%26%20rotor%20head.-Master.PDF - Allison Photo 89. Transmission & rotor head. (item 25, .PDF, 58 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041033&FileExtension=.PDF&FileName=Allison%20Photo%2089.%20%20Transmission%20%26%20rotor%20head.-Master.PDF - Allison Photo 92. Main rotor head. (item 26, .PDF, 54 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041034&FileExtension=.PDF&FileName=Allison%20Photo%2092.%20%20Main%20rotor%20head.-Master.PDF - Allison Photo 102. Main rotor blade. (item 27, .PDF, 67 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041035&FileExtension=.PDF&FileName=Allison%20Photo%20102.%20%20Main%20rotor%20blade.-Master.PDF - Allison Photo 103. Transmission gears. (item 28, .PDF, 62 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041036&FileExtension=.PDF&FileName=Allison%20Photo%20103.%20%20Transmission%20gears.-Master.PDF - Allison Photo 104. Transmission gears and drive shaft. (item 29, .PDF, 56 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041037&FileExtension=.PDF&FileName=Allison%20Photo%20104.%20%20Transmission%20gears%20and%20drive%20shaft.-Master.PDF - Allison Photo 110. Over-running clutch. (item 30, .PDF, 64 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041038&FileExtension=.PDF&FileName=Allison%20Photo%20110.%20%20Over-running%20clutch.-Master.PDF - Allison Photo 111. Over-running clutch. (item 31, .PDF, 57 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041039&FileExtension=.PDF&FileName=Allison%20Photo%20111.%20%20Over-running%20clutch.-Master.PDF - Allison Photo 112. Rotor drive shaft. (item 32, .PDF, 60 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041040&FileExtension=.PDF&FileName=Allison%20Photo%20112.%20%20Rotor%20drive%20shaft.-Master.PDF - Allison Photo 116. Tail boom assembly. (item 33, .PDF, 55 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041041&FileExtension=.PDF&FileName=Allison%20Photo%20116.%20%20Tail%20boom%20assembly.-Master.PDF - Allison Photo 117. Tail rotor assembly. (item 34, .PDF, 48 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041042&FileExtension=.PDF&FileName=Allison%20Photo%20117.%20%20Tail%20rotor%20assembly.-Master.PDF - Allison Photo 132. Horizontal stabilizer. (item 35, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041043&FileExtension=.PDF&FileName=Allison%20Photo%20132.%20%20Horizontal%20stabilizer.-Master.PDF - Allison Photo 133. Horizontal stabilizer. (item 36, .PDF, 56 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041044&FileExtension=.PDF&FileName=Allison%20Photo%20133.%20%20Horizontal%20stabilizer.-Master.PDF - Allison Photo 137. Bend in the tail boom. (item 37, .PDF, 47 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041045&FileExtension=.PDF&FileName=Allison%20Photo%20137.%20%20Bend%20in%20the%20tail%20boom.-Master.PDF - Allison Photo 138. Break in the tail boom. (item 38, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041046&FileExtension=.PDF&FileName=Allison%20Photo%20138.%20%20Break%20in%20the%20tail%20boom.-Master.PDF - Allison Photo 141. Underside hook assembly. (item 39, .PDF, 61 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041047&FileExtension=.PDF&FileName=Allison%20Photo%20141.%20%20Underside%20hook%20assembly.-Master.PDF - Allison Photo 142. Underside hook assembly. (item 40, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041048&FileExtension=.PDF&FileName=Allison%20Photo%20142.%20%20Underside%20hook%20assembly.-Master.PDF - Allison Photo 143. Basket rope, comparison. (item 41, .PDF, 40 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041049&FileExtension=.PDF&FileName=Allison%20Photo%20143.%20%20Basket%20rope,%20comparison.-Master.PDF - Allison Photo 157. Compressor inlet. (item 42, .PDF, 51 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041050&FileExtension=.PDF&FileName=Allison%20Photo%20157.%20%20Compressor%20inlet.-Master.PDF - Allison Photo 161. Compressor case half. (item 43, .PDF, 63 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041051&FileExtension=.PDF&FileName=Allison%20Photo%20161.%20%20Compressor%20case%20half.-Master.PDF - Allison Photo 162. Compressor rotor. (item 44, .PDF, 48 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041052&FileExtension=.PDF&FileName=Allison%20Photo%20162.%20%20Compressor%20rotor.-Master.PDF - Allison Photo 165. Spur adapter gearshaft. (item 45, .PDF, 47 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041053&FileExtension=.PDF&FileName=Allison%20Photo%20165.%20%20Spur%20adapter%20gearshaft.-Master.PDF - Allison Photo 169. Outer combustion case. (item 46, .PDF, 43 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041054&FileExtension=.PDF&FileName=Allison%20Photo%20169.%20%20Outer%20combustion%20case.-Master.PDF - Allison Photo 170. Combustion liner. (item 47, .PDF, 43 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041055&FileExtension=.PDF&FileName=Allison%20Photo%20170.%20%20Combustion%20liner.-Master.PDF - Allison Photo 181. Gearbox cover. (item 48, .PDF, 51 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041056&FileExtension=.PDF&FileName=Allison%20Photo%20181.%20%20Gearbox%20cover.-Master.PDF - Allison Photo 184. Mag plugs. (item 49, .PDF, 33 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041057&FileExtension=.PDF&FileName=Allison%20Photo%20184.%20%20Mag%20plugs.-Master.PDF - Pilot Information (item 50, .PDF, 3.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40413403&FileExtension=.PDF&FileName=Pilot%20Information-Redacted.PDF - Billy Pugh Nets Information (item 51, .PDF, 518 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041059&FileExtension=.PDF&FileName=Billy%20Pugh%20Nets%20Information-Master.PDF - Federal Air Regulations for Helicopter Operations (item 52, .PDF, 674 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40041060&FileExtension=.PDF&FileName=Federal%20Air%20Regulations%20for%20Helicopter%20Operations-Master.PDF - Statement of Party Representatives to NTSB Investigation (item 53, .PDF, 303 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40413404&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Redacted.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 54, .PDF, 45 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40413405&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-Redacted.PDF - Toxicological Report (item 55, .PDF, 63 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40413406&FileExtension=.PDF&FileName=Toxicological%20Report-Redacted.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.