24 March 2012

Cougar to replace gearbox on S-92 #nlpoli

Local media – CBC and Telegram for example – reported on Friday that Cougar Helicopters would “replace the  gearbox” on an S-92 that showed an indication of metal in the fluid of the Number 2 Input Module earlier in the week.

“Sikorsky analyzed data from its global Health and Usage Monitoring system and that analysis indicated an upward trend in a component,” she stated in an email to The Telegram this afternoon.

“This information, when combined with the information shown following an assessment of the elements related to the chip indication, reveal a possibility that this could be an early indicator of reduced performance.”

The Health and Usage Monitoring System (HUMS) is operated by the aircraft manufacturer, Sikorsky.  It analyses information from sensors located on Sikorsky helicopters operating worldwide.   A photograph from cougar.ca shows the sensor locations:


HUMS can be used to detect changes in how different parts of an individual aircraft work in daily flight and compare performance across the entire fleet of aircraft. Both the pilot and the co-pilot can monitor HUMS read-outs during flights.  Daily maintenance procedures include downloading the information from the helicopter’s onboard computers and feeding the information Sikorsky Aircraft

In this case, it appears that the HUMS analysis by Sikorsky Aircraft showed a pattern of readings for this particular aircraft  - the “upward trend” – for the gearbox that might indicate a problem at some point in the future.  Cougar opted to replace the engine components involved. 

Cougar Helicopters did not release the aircraft serial number for the helicopter involved in this incident.

- srbp -