S-92A Flying Control Restriction on Wiring Loom

A pilot recently reported a restriction of main rotor cyclic movement in the forward left quadrant of a Sikorsky S-92A according to a Service Difficult Report (SDR) submitted to the Civil Aviation Safety Authority (CASA) in Australia. The subsequent maintenance investigation found that a cyclic wiring loom was preventing full movement to the stop.

S-92A Loom Causing Control Restriction (Credit: via CASA)

S-92A Loom Causing Control Restriction (Credit: via CASA)

The wiring loom was rerouted to eliminate the restriction.

S-92A Loom Re-routed (Credit: via CASA)

S-92A Loom Re-routed (Credit: via CASA)

The SDR provides no further details on how, when or why the loom became misrouted.

See also our previous articles:

UPDATE 13 March 2017: The AIB Nigeria have only just released their report into a hydraulic pipe chafing event that caused a fire on 27 February 2013 on S-92A 5N-BOA.  It is rather unfair however of the AIBN to complain that the operator did not did not challenge the serial number applicability of an earlier 2008 Sikorsky ASB that (by implication) was to address production defects with a once off inspection.

Fire Damage on Sikorsky S-92A 5N-BOA After Hydraulic Pipe Chaffing (Credit: via AIBN)

Fire Damage on Sikorsky S-92A 5N-BOA After Hydraulic Pipe Chaffing (Credit: via AIBN)

Aerossurance is pleased to sponsor the 2017 European Society of Air Safety Investigators (ESASI) 8th Regional Seminar in Ljubljana, Slovenia on 19 and 20 April 2017.  Registration is just €100 per delegate. To register for the seminar please follow this link.  ESASI is the European chapter of the International Society of Air Safety Investigators (ISASI).

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UPDATE 17 September 2022: Canadian B212 Crash: A Defective Production Process 

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