# NTSB SEA96FA130: Hughes 269C, N7400F, Eldon, WA, June 19, 1996 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: June 19, 1996, 11:40 local (18:40 UTC) - Place: Eldon, WA - Coordinates: 47.519512, -123.059753 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=47.5195&lon=-123.0598&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal, 1 serious - Status: Completed, report April 3, 1997 - Report: Approved by Office Director - NTSB case key (mKey): 42276 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA96FA130 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/42276/pdf - Page: https://openairdocs.org/ntsb/SEA96FA130 ## Probable cause fatigue failure of the connecting rod cap, which resulted in loss of engine power and ditching at sea. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - mech failure/malf, cruise - engine assembly,connecting rod cap - fatigue (cause) - engine assembly,connecting rod - failure (cause) - Forced landing, emergency descent/landing - autorotation - performed, pilot in command - Ditching, emergency landing - terrain condition - water,rough ## Analysis While in cruise flight over Hood Canal, the rotorcraft began shaking, and a ground witness heard a 'pop' and observed white smoke. The pilot-in-command executed an intentional ditching, but was unable to swim to shore. The passenger survived. Postcrash examination revealed that the Lycoming HIO-360-D1A engine's number two connecting rod assembly had failed when the cap end had separated. Metallurgical examination revealed that the connecting rod cap had failed from fatigue and that both connecting rod bolts had failed in overload. The fatigue was associated with fretting within the rod cap inner face between the face and the bearing surface. ## Factual narrative HISTORY OF FLIGHT On June 19, 1996, approximately 1140 hours Pacific daylight time, a Hughes 269C rotorcraft, N7400F, being flown by a private pilot, sustained substantial damage during a collision with water following a total loss of power and forced ditching in Hood Canal near Eldon, Washington. The pilot and passenger exited the aircraft and the passenger was able to swim to shore with serious injuries. The pilot, who was observed swimming toward the shoreline by the passenger, was not recovered and is presumed to have drowned. Visual meteorological conditions existed and a company flight plan had been filed. The flight, which was personal, was to have been operated under 14CFR91, and originated from Shelton, Washington, approximately 1115. The passenger reported in an interview with an FAA inspector that while the rotorcraft was cruising approximately 400 feet above the surface of Hood Canal it began a hard and erratic shaking. He stated that the rotorcraft descended toward the water and was unable to reach the shoreline (refer to attached statements). A witness along the shore reported hearing a loud "pop" and seeing white smoke in the vicinity of the rotorcraft (refer to attached statements). A sonar search by the US Navy for the rotorcraft and pilot was unsuccessful. The rotorcraft was subsequently located by the owner and recovered on July 20, 1996, under the observation of an NTSB investigator. The wreckage was then secured by Mr. Don Hawks at the Shelton airport. AIRCRAFT INFORMATION The Lycoming HIO-360-D1A engine, serial number L-20456-51A, underwent a 100 hour inspection on April 27, 1996, and had a total of approximately 847 hours of operating time since its last major overhaul conducted on August 21, 1987. The engine's time of operation between the 100 hour inspection and the accident was approximately 91 hours and the engine's total time since new was approximately 5776 hours. The engine was installed in N7400F on August 16, 1990, with a total time of 4929.0 hours time since new. On March 4, 1995, at an engine total time of 5290.1 hours, the rotorcraft was involved in a blade strike/hard landing. No significant engine maintenance was accomplished immediately following that event (refer to ATTACHMENTS I & II). Then, on December 18, 1995, at a total engine time of 5539.3 hours, metal chips were detected in the engine oil. The engine was disassembled and repaired including the installation of new rod cap nuts and new rod bearings (refer to ATTACHMENT III). An FAA inspector telephonically interviewed the mechanic who performed the above referenced engine maintenance and was told that during the engine disassembly the rod end bolts were not replaced but were re-used, and that all maintenance accomplished on the engine was in accordance with the Lycoming maintenance manual (refer to attached statement). TESTS AND RESEARCH The engine was removed from the airframe by mechanics from Avstar Aviation, Inc., and was disassembled at the Avstar Aviation facility at the Pierce County airport on the afternoon of July 25, 1996. The Hobbs meter showed a reading of 437.1 hours when the engine was removed. The left engine case half was observed to have a large hole above the number two cylinder. The camshaft was observed to broken in two. The number two connecting rod was observed separated from the crankshaft and was missing the rod cap end (refer to photograph 1). Upon removal of the number two cylinder, fragments of the connecting rod cap end as well as its associated end bolts and nuts were recovered from within the engine. The pieces of the two connecting rod cap bolts including a section from the rod cap end still attached to one of the bolts, all from the number two connecting rod, were examined at the NTSB's Materials Laboratory. The fracture surface of the connecting rod cap end piece displayed arrest marks, consistent with a fatigue fracture. This was confirmed under examination utilizing a scanning electron microscope. Examination of the bearing (inner) surface of the rod cap end piece revealed fretting features indicating relative movement between the rod cap and the bearing shell. Both rod cap bolt pieces displayed fracture surfaces characteristic of overstress separations (refer to attached Metallurgical Report). The remainder of the engine was subsequently shipped to Lycoming where, under the control of an NTSB investigator, it was further disassembled and examined on September 27, 1996. The examination revealed evidence of fretting on the numbers one and three connecting rod cap half surfaces and evidence of galling on the inner diameter of the associated connecting rod cap bearing surfaces. Additionally, severe galling was observed on the numbers three and four connecting road bearing surfaces (refer to attached engine disassembly report). ADDITIONAL INFORMATION The Lycoming HIO-360-D1A engine was removed from the airframe by mechanics from Avstar Aviation, Inc., on the afternoon of July 24, 1996, and transported to the Avstar maintenance facility at Pierce County Airport, Puyallup, Washington. The engine was subsequently shipped to Lycoming for further examination and then shipped by Lycoming directly to Mr. James F. Irvin, Aircraft Engine Reconstruction Specialists, Bullhead City, Arizona. The engine and retained components were released to Mr. James Stiger of Barrus & Stiger on September 22, 1996 (refer to NTSB Form 6120.15 for documentation of retention and subsequent release of the engine, logs, and connecting rod bolts and associated components). ## Aircraft - Registration: [N7400F](https://openairdocs.org/deregistered/N7400F-2013-05-07), registration cancelled 2013-05-07, S/N 250397, built 1975 (OpenAirDocs) - Reported make and model: Hughes 269C - Registry model: [Hughes 269C](https://openairdocs.org/model/hughes-269c) (registry code 4470504) (OpenAirDocs) - Registry engine: [Lycoming I0360 series](https://openairdocs.org/engine/lycoming-i0360-series) (registry code 41515, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 250397 - Airframe hours: 2440 - Engines: Lycoming HIO-360-D1A 225 horsepower reciprocating - Damage: Destroyed - Flight: Personal, Part 91 - Operator: Olympic Air, Inc. - Registered owner: Fly Fishing, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, April 27, 1996, 91 hours before - Departed: SHN, SHELTON, WA - Destination: CLM, PORT ANGELES, WA - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 22; private; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 121 total, 90 in this make and model, 78 as pilot in command, 33 in the last 90 days, 15 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 360° at 10 knots - Visibility: 10 statute miles - Temperature: 66 °F, dew point 39 °F - Altimeter: 30.00 inHg - Observed at: PWT, 11 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 19960619014469A](https://openairdocs.org/incident/19960619014469A), Jun 19, 1996: Hughes 269C, Eldon, WA, Substantial damage, 1 fatal. Cruise over canal 400FT awl. Vibration. Descended into canal. Engine had thrown a rod. Prior sudden stop accident. ## Other investigations on N7400F (1) 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 SEA93LA001](https://openairdocs.org/ntsb/SEA93LA001), Oct 1, 1992: Hughes 269C (N7400F), Hillsboro, OR, substantial damage. Probable cause: THE PILOT IN COMMAND'S FAILURE TO MAINTAIN PROPER ALTITUDE DURING THE HOVER. FACTORS CONTRIBUTING TO THE ACCIDENT WERE THE PILOT IN COMMAND'S LACK OF TOTAL EXPERIENCE IN ROTORCRAFT AND HIS DIVERSION… 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.