21 March 2012

S-92 incident: March 2012, Newfoundland offshore #nlpoli

From the offshore regulatory board, March 21, 2012:

The C-NLOPB has been notified that on approach to the Terra Nova FPSO,  Cougar Helicopters experienced a #2 Input Module Chip Light illumination. On deck the crew discussed the matter with Cougar's Maintenance Control Centre (MCC).  It was decided to shut the aircraft down and complete a restart.  After restarting the light was still illuminated.  An engineer will be dispatched to the installation to investigate.

The input modules are part of the helicopter’s drive system.  They translate the energy from the two engines into the main rotor.  You can see the bits labelled in this diagram of a section of the main rotor assembly from the UH-60 Blackhawk.  The S-92 is derived from the Blackhawk.

uh60

The sensor that tripped is designed to detect metal fragments in the input module connected to the Number 2 engine.  Metal fragments would indicate wear inside a set of gears that turn at incredibly high rates.  That would not be good. The system also includes a device to get rid of tiny fragments and “fuzz” that might give false positive readings.

Here’s a portion of a U.S. Army training presentation on the transmission’s warning systems:

input

This is not the first time S-92’s flying offshore have reported this type of indicator.  Here are some extracts from the CADORS system, as posted to a helicopter pilots’ discussion site in 2009:

Date 1/18/2006
CADORS Number 2006A0038
Event Declared emergency/priority
Owner COUGAR HELICOPTERS INC
Description TSB Update A06A0005: CHI21, a Cougar Helicopter Sikorsky S-92A, with 18 passengers and two flight crew on board, was enroute from St. John's, NL to the Terra Nova FPSO oil production vessel when the number two engine chip light illuminated. …

Date 2/3/2006
CADORS Number 2006A0073
Event Engine malfunction - other
Owner COUGAR HELICOPTERS INC
Description CHI22,S92, enroute St. John’s (CYYT) to – Henry Goodrich Oil Platform (CHEN) requested to return to CYYT due indication light at 1800Z, position 35NM southeast of CYYT(St. John's). Aircraft advised no emergency. At approximately time 1813Z flight requested ERS on arrival. Landed without further incident at time 1823Z. Pilot advised of engine chip light. TSB Case Closed
Aircraft Model S92A
Aircraft Make SIKORSKY

Date 2/3/2006
CADORS Number 2006A0073
Event Engine malfunction - other
Owner COUGAR HELICOPTERS INC
Description UPDATE : TSB A06A0010: CHI22, a Cougar Helicopters Sikorsky S-92A, with 19 passengers and two flight crew onboard, was enroute from St. John's, NL to the Henry Goodrich oil platform and was approximately 35 NM Southeast of St. John's when the number two engine chip light illuminated (General Electric CT7-8A). The crew followed checklist procedures and reduced the #2 engine power to idle and elected to return to St. John's. The crew did not initially declare an emergency, however, ten minutes prior to landing requested ERS. The aircraft landed without further incident. After the aircraft landed, maintenance inspected the chip plug on the #2 engine and in consultation with the engine manufacturer, it was felt that the metal found on the chip plug was from the #3 bearing. This engine had a total of 42.2 hrs time in service since new. The engine was replaced with a new engine before the aircraft was returned to service.
Aircraft Model S92A
Aircraft Make SIKORSKY

Date 7/25/2006
CADORS Number 2006A0549
Event Declared emergency/priority
Owner COUGAR HELICOPTERS INC
Description UPDATE TSB: The number 2 engine had not failed rather a chip light had illuminated resulting in the flight crew reducing power for that engine.
Aircraft Model S92A
Aircraft Make SIKORSKY

Date 7/25/2006
CADORS Number 2006A0549
Event Declared emergency/priority
Owner COUGAR HELICOPTERS INC
Description UPDATE TSB: A06A0071: Cougar 33 (C-GSCH), a Sikorsky S-92, was outbound from St. John's to Hibernia. At approximately 75 nm from St. Johns the INPUT CHIP 2 light came on. The crew followed the checklist, reduced No.2 engine to IDLE, descended to 500 feet, and joined Route B back to St. John's airport. Once level at 500 feet the crew briefed the passengers and ATC. Approximately 5 minutes after the INPUT CHIP 2 indication the INPUT CHIP 1 also illuminated. The crew declared a "PAN" and continued in to St. John's at 500 feet. A Cormorant on exercises in the area (OUTCAST 903) joined the aircraft and escorted the flight in to St. John's airport. The crew flew a running landing onto Runway 02, then shut down the aircraft on the runway to prevent damage to the gearbox inputs. Upon inspection, the chip plugs in the main transmission and in the associated accessory modules were found to be contaminated. The affected components will be changed out, and the company and manufacturer are investigating the cause of the chip lights.
Aircraft Model S92A
Aircraft Make SIKORSKY

Date 7/25/2006
CADORS Number 2006A0549
Event Declared emergency/priority
Owner COUGAR HELICOPTERS INC
Description UPDATE TSB: A06A0071: Cougar 33 (C-GSCH), a Sikorsky S-92, was outbound from St. John's to Hibernia. At approximately 75 nm from St. Johns the INPUT CHIP 2 light came on. The crew followed the checklist, reduced No.2 engine to IDLE, descended to 500 feet, and joined Route B back to St. John's airport. Once level at 500 feet the crew briefed the passengers and ATC. Approximately 5 minutes after the INPUT CHIP 2 indication the INPUT CHIP 1 also illuminated. The crew declared a "PAN" and continued in to St. John's at 500 feet. A Cormorant on exercises in the area (OUTCAST 903) joined the aircraft and escorted the flight in to St. John's airport. The crew flew a running landing onto Runway 02, then shut down the aircraft on the runway to prevent damage to the gearbox inputs. Upon inspection, the chip plugs in the main transmission and in the associated accessory modules were found to be contaminated. The affected components will be changed out, and the company and manufacturer are investigating the cause of the chip lights.
Aircraft Model S92A
Aircraft Make SIKORSKY

Date 7/25/2006
CADORS Number 2006A0549
Event Engine malfunction - other
Owner COUGAR HELICOPTERS INC
Description UPDATE TSB: The number 2 engine had not failed rather a chip light had illuminated resulting in the flight crew reducing power for that engine.
Aircraft Model S92A
Aircraft Make SIKORSKY

Date 7/25/2006
CADORS Number 2006A0549
Event Diversion
Owner COUGAR HELICOPTERS INC
Description UPDATE TSB: A06A0071: Cougar 33 (C-GSCH), a Sikorsky S-92, was outbound from St. John's to Hibernia. At approximately 75 nm from St. Johns the INPUT CHIP 2 light came on. The crew followed the checklist, reduced No.2 engine to IDLE, descended to 500 feet, and joined Route B back to St. John's airport. Once level at 500 feet the crew briefed the passengers and ATC. Approximately 5 minutes after the INPUT CHIP 2 indication the INPUT CHIP 1 also illuminated. The crew declared a "PAN" and continued in to St. John's at 500 feet. A Cormorant on exercises in the area (OUTCAST 903) joined the aircraft and escorted the flight in to St. John's airport. The crew flew a running landing onto Runway 02, then shut down the aircraft on the runway to prevent damage to the gearbox inputs. Upon inspection, the chip plugs in the main transmission and in the associated accessory modules were found to be contaminated. The affected components will be changed out, and the company and manufacturer are investigating the cause of the chip lights.
Aircraft Model S92A
Aircraft Make SIKORSKY

Date 7/25/2006
CADORS Number 2006A0549
Event Diversion
Owner COUGAR HELICOPTERS INC
Description UPDATE TSB: The number 2 engine had not failed rather a chip light had illuminated resulting in the flight crew reducing power for that engine.
Aircraft Model S92A
Aircraft Make SIKORSKY

Date 6/13/2007
CADORS Number 2007A0519
Event Diversion
Owner COUGAR HELICOPTERS INC.
Description A Canadian registered Sikorsky S92A, after departure from St. John’s (CYYT), requested to return to the airport due to an input chip light indication. The aircraft landed without further incident at 11:12Z. Nil TSB.
Aircraft Model S92A
Aircraft Make SIKORSKY

Date 4/24/2008
CADORS Number 2008A0501
Event Engine failure
Owner COUGAR HELICOPTERS INC.
Description UPDATE TSB: A08A0059: The Cougar Helicopters Sikorsky-S92A , operating as CHI91, was in cruise flight en route from the Hibernia Gravity Based Platform to St. John's Intl. When the helicopter was approximately 100 NM SE of St. John's, NL the crew contacted Gander ACC to advise they were declaring an emergency and had shutdown engine #1 (GE CT7-8A). The engine shutdown was required due to a Gear Box chip light. The helicopter landed uneventfully at 12:35 NDT while ARFF were standing by. Maintenance determined the chip light was due to an accumulation of "nuisance fuzz" in the form of a "sliver" on a recently installed Main Gearbox accessory input.
Aircraft Model S92A
Aircraft Make SIKORSKY

- srbp -

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