Japanese Jetstar Boeing 787 GEnx-1B Engine Biocide Serious Incident
Jetstar Boeing 787-8 VH-VKJ General Electric GEnx-1B Engine Biocide Serious Incident near Kansai On 29 March 2019 the No 1 General Electric GEnx-1B engine of Jetstar Airways Boeing 787-8 VH-VKJ, flying from Cairns, Australia to Osaka Kansai International, Japan, fell below idle during the descent at an altitude of about 16,000 ft for 8 seconds. The No 2 engine then fell below idle too for 81 seconds. The aircraft safely landed at Kansai International less than 30 minutes later. The Japan Transport Safety Board (JTSB) explain in their safety investigation report (issued 25 June 2020) that engine rpm oscillations had been recorded during the incident. In fact oscillations had been recorded by the FDR since a fuel biocide treatment had occurred on 27 March 2019. However, these oscillations had been so small as not to have been noticed until the descent on 29 March 2019 when “ENG FAIL L” and “ENG FAIL R” EICAS messages also appeared. During the subsequent investigation… ….a residue, primarily composed of magnesium salts was observed in multiple locations (fuel filter, fuel metering valve [FMV] spool, fuel splitting valve [FSV] spool, variable bleed valve [VBV] spool and high pressure turbine [HPT] active clearance control [ACC spool]). Testing showed that up to 320 times more force was needed to move the control servos with the residue. The JTSB therefore concluded that when fuel pressure was low when descending at flight idle, “the FMV spool and FSV spool had restricted freedom of movement” and that the engines had dropped below idle due to the FSV sticking. JTSB say: It is probable that biocide treatment inside fuel tanks conducted two days before the serious incident was involved in the accumulation of [the] residue…because the composition of the residue were similar to the Kathon FP1.5. Biocide treatment is used to prevent microbial growth that can cause corrosion and damage fuel and engine systems. The Aircraft [had been] ferried to Auckland International Airport, New Zealand to borrow facilities of other company to conduct biocide treatment inside all three fuel tanks (left, center and right) because the Operator did not have their own facilities. …biocide treatment is conducted by connecting biocide treatment cart to a certain position of fueling hose to mix biocide with fuel for loading into fuel tank. AMM stipulates that biocide of either Kathon FP1.5 or Biobor JF is used, and the Operator used Kathon FP1.5. Kathon FP1.5 (MIL-S-53021A) composition is: Glycol: 90.0%, Water: 5.85%, Magnesium salts: 2.65%, 5-Chloro-2-Methyl-4-Isothiazolin-3-one: 1.15% and 2-Methyl-4-Isothiazoliln-3-one: 0.35%. The magnesium salts contained in Kathon FP 1.5 are insoluble in fuel but will dissolve into water if a water phase is present in the fuel. When Kathon FP1.5 is used, biocide and fuel are loaded to make concentration ratio inside fuel tank 100 ppm (parts per million) by volume. Therefore, in the event that fuel remains in aircraft, fuel and biocide to be loaded require adjustments to obtain a higher concentration ratio for loading into aircraft so that the final concentration ratio inside the tank can be 100 ppm. After completing fuel loading, biocide treatment is completed by soaking fuel for 12 to 24 hours keeping concentration ratio inside fuel tank at 100 ppm. The certifying staff involved had not recorded details of the biocide quantity added. JTSB comment that “It is desirable to keep these records because they are considered to be important for traceability of maintenance work.”. JTSB determines that the actual concentration was 250 ppm in...
read moreMyanmar National Embraer 190 NLG Jam: Maintenance Error? We’re Not Convinced!
Myanmar National Embraer 190 NLG Jam: Maintenance Error? We’re Not Convinced! (XY-AGQ, Mandalay) On 12 May 2019 Myanmar National Airlines Embraer 190 XY-AGQ suffered damage to its forward fuselage during the landing in Mandalay, on a flight from Yangon, after the Nose Landing Gear (NLG) failed to extend. The 89 occupants were unharmed. A maintenance error narrative was accepted without question by the technical press. We aren’t convinced! https://youtu.be/Jl5xXzj8n64 Safety Investigation The Aircraft Accident Investigation Bureau of Myanmar (AAIBM) issued their safety investigation report on 16 June 2020 (after just 13 months). They explain that analysis of the Flight Data Recorder (FDR), and the weight-off-wheels switch signal in particular, showed that as the NLG retracted the shock strut had compressed enough to disengage a self-centring cam which keeps the nose wheels central as the NLG enters the bay. The nose wheels turned and became offset by about 20°. Any more that 8° offset means the wheels will jam when the NLG is lowered, which is what happened. On 23 previous flights the weight-off-wheels switch signal had also changed from ‘WOffW=True’ to ‘WOffW=False’ during the retraction. The investigators concluded that a similar event could have occurred on those flights. The aircraft had previously undergone fault-finding to try to rectify a failure message relating to the weight-on-wheels system, first observed on 8 May 2019. The engineer involved stated that the aircraft had… …encountered a Landing Gear WOW System fault just after take-off from Yangon and returned to Yangon and the Pilot-in-command entered a Landing Gear WOW System fault message into the Technical Logs book. The engineer said that the maintenance action performed was cleaning the Nose Landing Gear sensors, connector and targets according to Fault Isolation Manual (FIM) (32-61-00-810-890-A00). After that he checked CMC [Central Mainteance Computer] of the aircraft, that there were no WOW SYS fault messages active. The aircraft was put back into service that day but on 11 May 2020, the crew felt the NLG vibrating during take-off and gear retraction. They recorded in the Technical Log records that “Nose Wheel Tension is Stronger than Normal During Take off and Landing Rolling”. Maintenance was performed that night, with the engineer stating that the task performed… …was the Nose Landing Gear shock Strut N2 Chamber Servicing, according to Aircraft Maintenance Manual (AMM) 12-12-09-600-804-A. He also stated this condition, was not included in FIM. Therefore, he decided on the appropriate maintenance action for this fault based on his experience. After that he checked the Dimension H of sliding tube of Nose Landing Gear based on the temperature 30ºC , it was within limit in the graph of (AMM) 12-12-09-600- 804-A. The accident occurred on the next flight. The AAIBM Conclusion The investigators concluded: Maintenance actions were not properly done as per the fault isolation manual in rectifying the intermittent Weight off Wheels System Fail fault and in addition, poor workmanship in performing the Nose Landing Gear Strut N2 servicing. Our Observations and Warnings on WYLFIWYF and the FFP Fallacy However, disappointingly, the investigators actually provided no evidence for their conclusions! They identify no omission or error by the first engineer. They don’t comment on the dilemma the second engineer faced, namely the absence from the FIM of the oddly phrased problem reported nor do the investigators assess the adequacy of the maintenance instructions in general. The investigators also do not identify why the N2 Chamber servicing was either incorrect or, indeed if correct, may have contributed to the jam on the 24th flight. There are also...
read moreA Try and See Catastrophe: R44 Accident in Norway in Bad Weather
A Try and See Catastrophe: Robinsion R44 LN-ORH Accident in Norway in Bad Weather On 17 February 2019 privately operated Robinson R44 II helicopter LN-ORH crashed in bad weather in steep mountainous terrain near Eskjeflota, Ullensvang municipality, Vestland county, Norway just 5 minutes after take off. Both occupants died instantly. Flight Preparations The Accident Investigation Board Norway (AIBN) explain in their safety investigation report (issued 17 June 2020) that: On Friday 15 February 2019, the commander, accompanied by his wife flew…from their residence in Karmøy to their holiday cabin in Røldal. They were planning to return to Karmøy on Sunday afternoon. At approximately 1100 hours on Sunday 17 February, the commander talked to one of his neighbors… As the neighbor understood it, the commander thought the weather was too bad to return home, but that it, according to the weather forecast, would improve around 1400–1500 hours. Later he spoke with a visiting friend who was the commander’s former instructor at a helicopter pilot training school in Florida. They discussed the poor weather and several possible routes. The available meteorological information shows that the weather was “challenging” say AIBN, with “relatively strong winds, clouds down to 400 ft, drizzle and fog in several places in the relevant area”. The commander indicated that he would make a precautionary landing should the weather deteriorate. While talking, they heard and spotted a helicopter from Fonnafly AS over the ski center, heading for the valley leading to Ullshaug and Eskjeflota. This was the same route that the commander was planning to fly. Shortly after, they heard a helicopter pass and thought it was another Fonnafly helicopter heading in the same direction. This was taken as confirmation that the preferred route was passable. It is now known the ‘second’ helicopter was actually the first Fonnafly helicopter returning having turned back due to poor visibility north west in the mountain pass. The commander decided to conduct the flight as planned, and they all left the cabin at approximately 1500 hours. In retrospect, the friend has expressed regret to the AIBN that he did not interfere more in the decision process when they discussed the weather conditions and the imminent flight. However, he was not in a formal position to intervene. The Accident Flight A video recording made by a witness at the ski center shows that the helicopter took off in a southwesterly direction from Røldal Terrasse at 1519 hours. It then made a right turn heading northwest in the direction of the top of the ski lift at Røldal Ski Center and Røldalsfjellet. The commander had installed a GoPro camera on the instrument panel on the helicopter’s righthand side. The camera recorded the entire flight, from just after take-off… The video shows that, shortly after take-off, the helicopter entered an area with low clouds and poor visibility. In increasingly poor visibility the flight continued for about three minutes until the commander stopped and turned the helicopter around while it was more or less hovering. The helicopter then made a turn to the right and continued flying for about 10 seconds before all visual references disappeared from the video. The flight continued for 84 seconds with no visual camera references outside the cockpit. The terrain became visible again for two seconds before the helicopter dived and crashed into the terrain with great force. The entire flight lasted just under 5 minutes. The helicopter was equipped with a Kannad 406 AF Compact Emergency Locator Transmitter. The transmitter activated automatically as intended, but [as is common in helicopter accidents]...
read moreCRJ-200 Landing Incident Highlighted US Maintenance Competency Inadequacies
CRJ-200 Landing Incident Highlighted US Maintenance Competency Inadequacies (Air Wisconsin N707AW) On 14 December 2008, Air Wisconsin Bombardier CRJ-200 (CL-600-2B19) N407AW, made an emergency landing at Philadelphia International (PHL), Pennsylvania, with the left Main Landing Gear (MLG) retracted position. The long delayed US National Transportation Safety Board (NTSB) final report points to a series of maintenance standards and competency issues in this incident. Planned rulemaking to solve these was abandoned by FAA after 5 years however. The Incident Flight The NTSB explain in their safety investigation report (only issued 6 April 2020 after 11.25 years!) that the aircraft on a flight from Norfolk International (ORF), Virginia to operate for US Airways after scheduled maintenance, namely… …both the right and left main landing gear uplock assemblies were replaced as required by the air carrier’s airplane component time limitation (20,000 cycles). The flight crew had indications of a landing gear problem during approach. After unsuccessfully attempting to lower the gear, the flight crew elected to make an emergency landing with only the nose gear and right main landing gear “down and locked”. After touch down, the airplane came to rest on its right main landing gear, nose gear and the left wingtip and flaps, resulting in minor damage. The Safety Investigation The left and right MLG uplock assemblies had been replaced during the maintenance. No anomalies were found with the installation of the right MLG uplock assembly; however, the upper attachment bolt in the left MLG uplock assembly was improperly installed and had not properly been inspected. The left uplock assembly’s upper attachment bolt, nut, and cotter pin assembly were installed but the NTSB say “these did not engage the uplock assembly”. This allowed the uplock assembly to pivot about the lower bolt. As the upper attachment bolt did not engage the uplock assembly, the left MLG remained in the up-and-locked position and could not be released by the flight crew. The investigative team reviewed the Air Wisconsin, Inc. removal and installation maintenance manual for the MLG Uplock Assembly (MM 32-32-05 page 401-407, dated April 20, 2004). The contents of the maintenance manual were the same as the Bombardier CRJ MLG Uplock Assembly manual. Both manuals outline instructions to install both bolts through the uplock assembly and to the aircraft structure. It was noted that the instructions did not mention of the spacer located between the uplock assembly attachment lugs and that the orientation of Figure 401 was confusing when referenced to install the left uplock assembly. The instructions also failed to reference a nearby hydraulic line cover that had to be removed in order to remove the uplock assembly attachment bolts. NTSB explain that: The investigation revealed that at the maintenance facility two separate mechanics had been assigned to replace each of the uplock assemblies on the airplane. The installation of both assemblies could not be completed during the midnight shift (2130 to 0730), and the mechanic who replaced the left uplock departed when the shift was over. Removal and installation of the uplock assemblies is a required inspection item (RII) and must be inspected by an RII inspector. The inspection noted [three] discrepancies in the installation of the left gear assembly installation, which were corrected by the mechanic (at the request of the inspector) who stayed past his shift and installed the right uplock assembly; however the discrepancies were not properly documented. It is...
read moreFreewheel Jerk on an SA330J Puma at Sea: Oil Analysis Opportunity
Freewheel Jerk on an SA330J Puma at Sea: Oil Analysis Opportunity (Erickson Helicopters Airbus SA330J N339EV) On 26 January 2018 Airbus Helicopters SA330J N339EV, operated by Erickson Helicopters, sustained substantial damage during a fresh water engine rinse aboard the replenishment vessel USNS Wally Schirra underway in the Pacific. The helicopter was operating under Part 133 (external load) and had been shuttling supplies, known as VERTREP, to other naval vessels in the area. The US National Transportation Safety Board (NTSB) explain in their safety investigation report (issued 3 June 2020) that… …after landing the helicopter on the deck of the ship, power was increased on the No. 2 engine, while the No. 1 engine was reduced to ground idle in preparation for a freshwater rinse of the engines to prevent corrosion. Once the engines were configured, the pilot saw the lead mechanic squeeze the trigger on the wand, and then there was a rumbling sound followed by a rough shudder through the airframe. He then looked back at the cockpit instruments and everything looked normal for the condition the controls were in at the time. About that time, there was another shudder through the airframe, and he heard a change in the tone of the engine and gear box noise. He saw that the rotor speed had started to rise, and the gas generator speed of the No. 2 engine had also started to increase. He shut down the engines. The Tail Rotor Drive Shaft (TRDS) was found to have sheared, disconnecting the Main Gear Box from the Tail Rotor. Safety Investigation Examination of the MGB right freewheel assembly revealed that the small roller bearings were dislocated, the bearing cage was fragmented, and both tabs of the shur-lok washer showed signs of deformation with visible impact damage. Damage to these tabs is consistent with a sudden engagement of the bearing, resulting in an instantaneous spike in torque, known as freewheel jerk. During the transition of the No. 2 engine from the idle position to the flight position, the condition of the freewheel small roller bearings likely prevented the freewheel cage from maintaining the large freewheel rollers on the ramp due to the effect of the freewheel spring. This situation is unstable until an “imbalance” modifies it and suddenly causes the cage and the freewheel rollers to rise on the ramp, imparting a torque spike into the rotor drive system. NTSB say that oil analysis had the potential for early detection of the freewheel unit failure mode: The maintenance manual for the SA330 helicopter requires the oil analysis be performed every 150 hours for the main gear box and every 50 hours for the intermediate gear box. Laboratory results were obtained from the two prior oil samples. The two samples taken were 88.4 hours and 2 years apart [indicating very low utilisation or a period of storage]. The first, dated February 13, 2016 listed Fe at 3.3 parts per million. The second sample, taken in November of 2017 [albeit prior to the 150 hour interval] was misplaced by the operator and not found until after the accident. When it was sent for analysis on February 4, 2018, Fe was detected at 14.7 parts per million. …had both of these samples been analyzed at the time of the inspection, it is likely the operator would have been able to detect the increase in metal before the bearing wear became severe enough to cause the jerk. Oddly while the NTSB laboratory documented an examination of the TRDS, the FWU wasn’t examined. Safety Action After the accident, the operator implemented an internal requirement for oil...
read moreVisual Illusions, a Non Standard Approach and Cockpit Gradient: Business Jet Accident at Aarhus
Visual Illusions, a Non Standard Approach and Cockpit Gradient: Business Jet Accident at Aarhus (Aerowest C560XLS+ D-CAWM) On 5 August 2019 business jet Cessna 560 XLS+ D-CAWM of Aerowest. inbound from Oslo, was destroyed landing at Aarhus (EKAH). The 3 crew and 7 passengers were able to evacuate without injury. The Accident Flight The Accident Investigation Board Denmark (AIBD) explain in their safety investigation report (issued 10 June 2020) that: The commander was the pilot flying, and the first officer was the pilot monitoring. The commander was an experienced pilot and highly ranked at the operator. [This was the] first officer’s first job as a commercial pilot. As a consequence of the [first officer’s] latest OPC [Operator Proficiency Check] grading, the Head of Training & Standards restricted the first officer to fly only with supervision commanders. An on-board cabin crewmember was not a formal requirement for this aircraft type. The cabin crewmember had not received specific aircraft type training (not required) and was not formally responsible for on-board cabin flight safety The accident occurred in dark night under Instrument Meteorological Conditions (IMC). The forecasted weather conditions at EKAH were generally consistent with the actual weather reports…. Fog could be expected and was present at EKAH. However, on initial radio contact with Aarhus Tower, the first officer perceived, noted, and read back to the commander the meteorological visibility to be 2500 m instead of the reported 250 m. AIBD suggest this may have created a false perception that the visibility was better than it actually was. Aarhus Tower had also stated that… Runway Visual Range (RVR) at landing to be 900 m, 750 m, and 400 m in fog patches. The commander made an approach briefing for the Instrument Landing System (ILS) for runway 10R including a summary of SOP in case of a missed approach. The flight crew performed the approach checklist [and] discussed the weather situation at EKAH with expected shallow fog and fog patches at landing. The commander informed the first officer that the intention was to touch down at the beginning of the runway. In order to avoid entering fog patches during the landing roll, the commander planned flying one dot below the GS [Glide Slope], performing a towed approach, and touching down on the threshold. However, the commander did not communicate this plan of action to the first officer. The aircraft started descending below the GS for runway 10R. The first officer asked the commander whether to cancel potential Enhanced Ground Proximity Warning System (EGPWS) GS warnings. The commander confirmed. The aircraft aural alert warning system announced passing 500 feet RH. The recorded computed airspeed was 125 kt, the recorded vertical speed was approximately 700 ft/minute, and the GS deviation approached one dot below the GS. The commander noted the PAPI indicating the aircraft flying below the GS (one white and three red lights). The first officer called “Approaching minimum”. Shortly after, the aircraft aural alert warning system announced “Minimums Minimums”. The FDR recorded a beginning thrust reduction towards flight idle and a full scale GS deviation (flying below). The commander called “Continue”. The commander had visual contact with the approach and runway lighting system. It was the perception of the first officer that the commander had sufficient visual cues to continue the approach and landing. The first officer as pilot monitoring neither made callouts on altitude nor deviation from GS. The commander noticed passing a white crossbar,...
read moreB767 Fire and Uncommanded Evacuation After Lockwire Omitted
B767 Fire and Uncommanded Evacuation After Lockwire Omitted (Dynamic B767-200 N251MY at Fort Lauderdale, FL) On 29 October 2015 Dynamic International Airways Boeing 767-200ER N251MY, powered by Pratt & Whitney JT9D-7R4E4 engines, experienced a fuel leak and fire on the ground at the Fort Lauderdale-Hollywood International Airport, Florida (FLL). One of the 100 passengers received serious injuries from jet blast, 21 minor injuries and the aircraft sustained substantial damage. The Accident The US National Transportation Safety Board (NTSB) explain in their safety investigation report (issued 8 June 2020): A significant fuel leak and subsequent fire occurred in the left engine strut and nacelle during taxi… The flight crew promptly shut down the left engine using the fire handle, and requested fire equipment. The “A” flight attendant activated the emergency signaling system…to notify the flight deck and other crewmembers of an emergency. The chime was audible in the CVR recording, but the flight crew did not respond via interphone. There was no indication on the CVR of an evacuation checklist or communication between the cabin and flight deck. As the airplane stopped on the taxiway, passengers saw the fire and insisted that the cabin crew initiate an evacuation. One passenger opened an overwing exit on his own, and the slide did not deploy. The cabin crew initiated the evacuation without coordination with the flight crew. After the evacuation had already begun, the flight crew advised over the PA to evacuate out the right side of the airplane. The flight crew did not immediately shut down the right engine and an evacuating passenger ran behind the engine [about 11 seconds after the aircraft was stopped] and was blown to the pavement resulting in serious injuries. The lack of coordination between the flight crew and cabin crew resulted in the evacuation initiating while the right engine was still running. About 35 seconds later, the number 2 engine was shut down. About 54 seconds after the airplane stopped, an airport authority official arrived, and repositioned the 2R slide. About one minute later, airport firefighting vehicles arrived and began extinguishing the fire. https://youtu.be/9K3HDfhgdXo The Safety Investigation During a visual examination of the left engine and strut, a fuel coupling assembly was found separated with the coupling body pushed aft on a main fuel supply line. There were indications of fuel leakage at the flange interface of the fuel supply lines where the coupling had separated including discoloration from fluid pooling in the strut compartments and streaking down the left engine cowling. There was no safety lockwire present on either the body or nut side of the fuel coupling as required in the Boeing aircraft maintenance manual (AMM), and no broken lockwire was recovered in the surrounding strut compartments. A material examination of the fuel supply lines and coupling components verified that the parts met dimensional drawing specifications and were free of defects or damage that would have affected normal operation. In 2012, the airplane was placed in storage until 2015 when it was taken out of storage and prepared for leasing to Dynamic. A Boeing Service Letter recommending replacement of fuel line flexible coupling (Wiggins coupling) retainer components was issued on March 14, 2000. Maintenance records of the accident airplane indicate the last time this service was performed was by Kalitta Air LLC on October 12, 2012 just prior to going into...
read moreFatal Falcon 50 Accident: Unairworthy with Unqualified Crew
Fatal Falcon 50 Runway Excursion Accident: Unairworthy with Unqualified Crew On 27 September 2018 Dassault Falcon 50 N114TD, operated by Air America Flight Services on a Part 135 on-demand air taxi flight, was destroyed in a runway excursion at Greenville Downtown Airport (GMU), South Carolina. The two pilots were fatally injured. The two passengers were seriously injured. The Accident Flight The US National Transportation Safety Board (NTSB) explain in their safety investigation report (issued 3 June 2020) that: The Dassault Falcon 50 is a midsize long-range business jet. According to the cockpit voice recorder (CVR), during the approach to GMU, the flight crew had difficulties understanding the navigation fixes that air traffic control had provided. The CVR also showed that the flight crew did not use any prelanding checklist or discuss that no braking was available with the brake system in the “#1-ON” position (the pilot was the copilot for the previous four flights in the airplane, during which this condition was present). The “#1-ON” position of the switch selected normal braking utilizing system 1, and provided antiskid protection, while the “2-OFF” position selected emergency braking and did not provide antiskid. According to the pilot who conducted four flights in the airplane before the accident flight, upon application of the brakes with the brake switch in the “#1-ON” position, braking was normal at low speeds (estimated to be 15-20 knots) but at faster speeds, no braking was available. Braking was restored when the brake switch was placed in the “#2-OFF” position. This pilot [who who commanded the four flights prior] stated that he reported the brake system failure to the company’s Director of Maintenance after the first two flights (in late August and early September 2018) and indicated his belief that the source of the problem was the antiskid system. In interview with the Director of Maintenance, the son of the accident co-pilot, denied that he had been told. He also stated there were no defects deferred on the aircraft and the NTSB found no maintenance records indicating a brake system issue. However: Next to the switch, a green sticker was affixed to the panel with the label “ATA # 32-5 “INOP” DATE: 9/27/18”. The NTSB go on: At 1345:34, the CVR recorded the sound of the airplane touching down. At 1345:38, the pilot stated that the brakes were not operating. He and the copilot commented about the lack of brakes several more times before the airplane went over an embankment and came to a stop. Air traffic controllers at GMU reported that the airplane touched down “normally” at a standard touchdown point on the runway. They saw the airplane’s thrust reverser deploy and watched as the airplane continued down the runway without decelerating. An airport security video captured the airplane’s touchdown and showed that the thrust reverser and the airbrakes were deployed. The video [below as stills with time in lower left corner] also showed the airplane as it continued to the end of the runway and went over the embankment. A second video: [The aircraft had] departed the left edge of the runway [19] near the departure end, traveled across the flat grassy area at the end of the runway, continued down a 50-foot embankment, and came to rest on the airport perimeter road about 425 ft from the runway. The wreckage was oriented on a heading...
read moreFish Spotting Helicopter Strikes ‘Glassy’ Sea
Fish Spotting Helicopter Strikes ‘Glassy’ Sea (VSC H369D N8648F, from Tuna Boat Jib Yu 868 off Nauru in the Pacific) On the morning of 5 July 2018 MD Helicopters (Hughes) 369D helicopter N8648F of Vertol Systems Company (VSC) impacted the Pacific Ocean near Nauru in Micronesia. This occurred about 30 seconds after takeoff from a Taiwanese-registered fishing vessel, Jib Yu 868, a 70 m tuna purse seiner of the Chern Lung Fishery. The US pilot and the Taiwanese fish-spotter received fatal injuries. The US National Transportation Safety Board (NTSB) explain in their safety investigation report (dated 19 May 2020) that: The pilot and the turbine-powered, float-equipped helicopter were stationed on the ship, and a Taiwanese observer provided fish-spotting services. VSC leased helicopters and pilots to multiple companies, including foreign fishing companies operating in the southern and western Pacific Ocean. VSC had a logistics and maintenance base on Majuro (in the south Pacific Ocean) to facilitate these operations. Helicopters and pilots under contract were stationed on fishing ships, but no helicopter maintenance personnel were stationed on the ships. VSC would provide ship-board maintenance and maintenance personnel on a temporary, as-required basis. According to the available evidence, no VSC maintenance personnel were aboard the fishing ship during the days before or on the day of the accident. The Accident Flight Most of the brief flight was captured by a shipboard surveillance camera. The camera faced forward, with a field of view that included the helicopter on the landing platform, as well as the ocean surface forward of and on both sides of the ship. The ocean surface appeared glassy, with only slight swells and no waves. Glassy water make it difficult to judge an aircraft’s height above the water. We discussed this in: Austrian Police EC135P2+ Impacted Glassy Lake, which was similar to accident that occurred in New Zealand to Hughes 369 ZK-HXZ in 2012 (discussed in an NZCAA accident report). The helicopter lifted off and immediately entered a right descending turn, flying out of view on the right side of the image. Several seconds [actually about 12 seconds] later, the helicopter re-entered the field of view via the upper right image frame. The helicopter was traveling nearly horizontal from right to left at an altitude that was sufficiently low for visible ripples to form on the water surface behind the helicopter. The helicopter struck the water, overturned, and remained afloat inverted. Skiff boats responded to the accident location within minutes, and both helicopter occupants, who were still strapped into their seats [which has 4 point harnesses], were recovered but unable to be resuscitated. VIDEO: available on the Aerossurance LinkedIn news feed. According to the CCTV video footage timestamp the impact occurred c30 seconds after takeoff (not 20 seconds as stated by the NTSB). The helicopter was destroyed by impact forces and salt water immersion. …examination of the helicopter revealed no evidence of any mechanical anomalies that would have prevented continued flight… Two days earlier the helicopter, parked outside on the ship’s helideck, was exposed to a significant storm. Subsequently, the pilot had difficulty starting the engine. However, the NTSB do not believe this was relevant to the accident. The autopsy report [on the pilot] concluded that there was no significant natural disease or trauma, and that the pilot’s cause of death was “probable drowning.” No details are recorded of the fish-spotter’s cause of death but it was noted he also...
read moreBeechcraft 1900C Landing Gear Collapse at San Antonio, TX
Beechcraft B1900C Landing Gear Collapse at San Antonio, TX, 8 May 2020 (Ameriflight, N31704) On 8 May 2020 Ameriflight Beechcraft 1900C N31704 was damaged in an accident at San Antonio, Texas. The aircraft was being flown single pilot as a Part 135 cargo flight. The US National Transportation Safety Board (NTSB) preliminary report states that: …the flight departed the Corpus Christi International Airport (CRP), Corpus Christi, Texas, at 2004 with 631 lbs of cargo and a fuel load of 2,800 lbs. During the initial climb, the captain selected the landing gear handle to the UP position to retract the landing gear. The attempt was unsuccessful, and the captain attempted to cycle the landing gear handle once more yielding the same result. Following the second unsuccessful gear retraction, the captain elected to leave the landing gear handle in the DOWN position and continued to the San Antonio International Airport (SAT), San Antonio, Texas, where more services would be available if needed. The airplane climbed to 8,000 ft mean sea level and cruised below the maximum landing gear extended speed (VLE). Nearing San Antonio, the pilot completed the before landing checklist and noted ‘three greens’ which indicated the landing gear was down and locked. However… As the main landing gear touched down…the left main landing gear collapsed, the red unsafe light in the landing gear handle illuminated…followed by an aural horn indicating the landing gear was now unlocked and unsafe for landing. Simultaneously, the airplane began to dip toward the left, causing the left wing tip to contact the runway [which resulted in] momentum taking the airplane from the runway centerline off the runway and into the grass area several thousand feet from the runway 4 threshold. Once the airplane came to a complete stop, the captain shutdown all power to the airplane and exited through the main entry air stairs. A postaccident damage assessment by the operator revealed that the left main landing gear brace was fractured. The operator reported that the airplane’s weight at the time of the accident was 14,381 lbs (the airplane’s maximum gross weight is 17,120 lbs). UPDATE 30 March 2022: NTSB Final Report & Probable Cause Issued The NTSB final report reveals: …the left main landing gear upper drag leg arm fractured in bending and twisting overload. There was no evidence of preexisting cracking or corrosion. The dimensions of the part were consistent with the drawing and the chemical composition and microstructure were consistent with 7075 aluminum alloy, as required. The mechanical properties were lower, and the electrical conductivity was higher than the requirements for 7075-T6 aluminum alloy. The measured mechanical properties and electrical conductivity did not conform to any standard temper for 7075 aluminum alloy. The NTSB probable cause was determined to be: The failure of the left main landing gear upper drag leg arm due to substandard mechanical properties, which resulted in a collapse of the landing gear upon landing. Safety Resources Our past B1900, B99 and King Air safety articles include: B1900D Emergency Landing: Maintenance Standards & Practices Beech 99A MLG Collapse Incorrectly Rigged B1900D Charlotte, NC, 8 January 2003: 21 Fatalities Crossed Cables: Colgan Air B1900D N240CJ Maintenance Error B1900C PSM+ICR Accident in Pakistan 2010 Distracted B1900C Wheels Up Landing in the Bahamas Operator & FAA Shortcomings in Alaskan B1900 Accident Alaska B1900C Accident – Contributory ATC Errors B1900D Window Blowout King Air...
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