ERJ-190 Flying Control Rigging Error

The Portuguese accident investigation agency, GPIAAF, issued a safety investigation update on a serious in-flight loss of control event involving Air Astana Embraer ERJ-190 P4-KCJ that occurred on 11 November 2018 immediately after maintenance at the OGMA facility at the Alverca Air Base.  This was a ferry flight back to Kazakhstan with 6 persons on board not a maintenance check flight.

In-Flight Upset to, Air Astana Embraer EJ-190 P4-KCJ (Credit: Embraer via GPIAFF)

In-Flight Upset to, Air Astana Embraer EJ-190 P4-KCJ (Credit: Embraer via GPIAFF)

The aircraft was landed safely but with structural damage sufficient to make this an accident in accordance with ICAO Annex 13.  The crew had however encountered considerable difficulty controlling the aircraft, so much so they had debated ditching offshore.  However they regained a degree of control.  After two unstabilised approaches, the crew landed runway 19L. The intended runway was 19R, but due to lateral drift they were forced to land on 19L. https://youtu.be/6n4mQvO4-tE https://youtu.be/98z41SwaVOQ

Safety Investigation

GPIAAF confirmed that an incorrect aileron control cable system installation had occurred in both wings during the maintenance check conducted in Portugal.

Misrigged Flying Control Cable, Air Astana Embraer EJ-190 P4-KCJ (Credit: GPIAFF)

Misrigged Flying Control Cable, Air Astana Embraer EJ-190 P4-KCJ (Credit: GPIAFF)

GPIAFF note that:

By introducing the modification iaw Service Bulletin 190-57-0038 during the maintenance activities, there was no longer the cable routing and separation around rib 21, making it harder to understand the maintenance instructions, with recognized opportunities for improvement in the maintenance actions interpretation.

They comment on a problem with fault-finding that:

The message “FLT CTRL NO DISPATCH” was generated during the maintenance activities, which in turn originated additional troubleshooting activities by the maintenance service provider, supported by the aircraft manufacturer. These activities, which lasted for 11 days, did not identify the ailerons’ cables reversal, nor was this correlated to the “FLT CTRL NO DISPATCH” message.

Its possible, but not confirmed or discussed by GPIAAF, that the 11 days of fruitless fault-finding may have resulted in a delay and pressure to release the aircraft. GPIAFF comment that “deviations to the internal procedures” occurred within the third-party Part-145 maintenance organisation that “led to the error not being detected in the various safety barriers designed” in the process. They do not comment on what deviations occur, why they occurred or crucially how clear and practical those internal procedures were.  They do say that the maintenance organisation is making changes.  The investigators also suggest that the Type Certificate Holder review their documentation too. They also note that the error “was not identified in the aircraft operational checks (flight controls check) by the operator’s crew.” They add that:

Amongst other issues, the safety investigation will look into the aircraft design and functioning, the crew procedures and human factors aspects raised, and will now focus on the maintenance procedures and applied aircraft technical documentation, as well as the human and organizational factors involved in the Part-145 service provider.

We will publish more as the investigation develops.

Safety Resources

We also wrote Crossed Cables: Colgan Air B1900D N240CJ Maintenance Error.  In 2003 a B1900D crashed on take off after errors during flying control maintenance. We looked at the maintenance human factors safety lessons from this and another B1900 accident that year. We have previously discussed Misrigged Flying Controls: Fatal Maintenance Check Flight Accident, involving a Piper PA-46-350P Malibu Mirage (N962DA) in 2015, Too Rushed to Check: Misrigged Flying Controls involving a Piper PA-12 (N3280M) in 2017 and FAA Rules Applied: So Misrigged Flying Controls Undetected involving a Cessna 172M Skyhawk II (N9085H) in 2018. https://youtu.be/kN-N7D_hrS4 We have also discuss in the past two cases were the normal sound airmanship of pre-flight ‘full and free’ control checks would have prevented an accident:

In 1992 the gust locks had not been fully disengaged on a third-party DHC-4T Turbine Caribou conversion, N400NC, leading to a horrific fatal accident that killed 3.

We have previously written:

Aerossurance worked with the Flight Safety Foundation (FSF) to create a Maintenance Observation Program (MOP) requirement for their contractible BARSOHO offshore helicopter Safety Performance Requirements to help learning about routine maintenance and then to initiate safety improvements: mop Aerossurance can provide practice guidance and specialist support to successfully implement a MOP. An excellent initiative Human Hazard Analysis (HHA) that could help identify problematic maintenance tasks and improvements is described in Designing out human error

HeliOffshore, the global safety-focused organisation for the offshore helicopter industry, is exploring a fresh approach to reducing safety risk from aircraft maintenance. Recent trials with Airbus Helicopters and HeliOne show that this new direction has promise. The approach is based on an analysis of the aircraft design to identify where ‘error proofing’ features or other mitigations are most needed to support the maintenance engineer during critical maintenance tasks.

Other manufacturers and MROs are expanding the use of HHA during 2019.

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Aerossurance was pleased to both sponsor and present at a Royal Aeronautical Society (RAeSHuman Factors Group: Engineering seminar Maintenance Error: Are we learning? on 9 May 2019 at Cranfield University where we advocated a more sophisticated and holistic approach. raes are we learning

Aerossurance has extensive air safety, operations, airworthiness, human factors, aviation regulation and safety analysis experience.  For practical aviation advice you can trust, contact us at: enquiries@aerossurance.com