News: S92A Alert Service Bulletin & AAIB Special Bulletin
13 February 2017
Sikorsky issued the following update on the Tail Rotor Pitch Change Shaft (TRPCS) bearing inspections associated with ASB 92-64-011:
“Following the fleet-wide inspection notice, the great majority of operators are reporting compliance with the physical inspections outlined in the Alert Service Bulletin, and those who are not yet in compliance are working towards completion.
Additionally, Sikorsky continues to review the HUMS data as provided by the operators. To date, we have received a small number of returned parts and all of those parts are currently being evaluated. We continue to work closely with our supply chain on replacement parts and are coordinating those activities with our operators. We are cooperating with and assisting the investigative authorities as requested and cannot provide further comment as the AAIB investigation is ongoing.
We continue to update all operators via our webcasts and standard communication channels. Safety remains our highest priority, and we will further communicate findings to our operators if the investigation reveals any safety or airworthiness issues that affect the S-92 helicopter fleet.”
16 January 2017
EASA today issued an Emergency Airworthiness Directive: EAD US-2017-02-51 – SIKORSKY: Tail Rotor Control System – Tail Rotor Pitch Change Shaft Assembly Bearing – Removal / Inspections / Replacement
To see the details of this Publication, please click or copy the following: http://ad.easa.europa.eu/ad/US-2017-02-51
13 January 2017
We have received the Emergency Airworthiness Directive (AD) 2017-02-51 issued today, 13 January, by the Federal Aviation Administration (FAA) relating to the S-92A helicopter model. Click here to read the AD.
Sikorsky has issued a statement relating to the AD:
“The FAA issued an Emergency Airworthiness Directive on January 13 following Sikorsky’s January 10 Alert Service Bulletin. We appreciate the FAA’s mandate of the inspection of the S-92 Tail Rotor Pitch Change Shaft Assembly as it supports the continued airworthiness of the S-92 fleet and our top priority, safety.”
13 January, PM Update from Sikorsky:
“Physical inspections of the tail rotor pitch change shaft bearing are well underway with over 250 aircraft inspected. Sikorsky has been reviewing HUMS data from those aircraft as well. A small number of parts are being returned to Sikorsky for additional evaluation. These findings do not constitute failure of the bearing and are being returned to Sikorsky for further evaluation. Sikorsky continues to work closely with our supply chain on replacement parts and is coordinating those activities with our Customers.”
HeliOffshore CEO, Gretchen Haskins said: “These inspections are a precautionary measure to ensure safety, the operators are complying with Sikorsky’s Alert Service Bulletin and collaboration across the safety system is progressing well.”
11 January 2017
The UK Air Accidents Investigation Branch has published a Special Bulletin regarding the S92A incident on 28 December 2016 – the Special Bulletin is published to provide preliminary information gathered from an initial ground inspection, recorded data and other sources:
Statement from Sikorsky
We greatly appreciate the UK Air Accidents Investigation Branch’s work to understand this issue, and we will continue to support the ongoing investigation by the AAIB along with the NTSB, as well as our customer, into the root cause of the suspected TRPCS Bearing failure. Safety remains our highest priority, and operators are reporting compliance and completion of the inspections we required in our Jan. 10 Alert Service Bulletin and are returning their S-92 aircraft to service.
We are committed to keeping our customers informed. We will further communicate findings to our operators if the investigation reveals any safety or airworthiness issues that affect the S-92 helicopter fleet. We continue working closely with HeliOffshore to keep the offshore oil community informed.
10 January 2017
We recognise that the Alert Service Bulletin (ASB) issued today by helicopter manufacturer Sikorsky in relation to S92A aircraft will disrupt the offshore oil and gas industry in the short term.
This is a requirement to undertake a global fleet-wide inspection; it is not a grounding.
Such bulletins are an important part of the global aviation safety system, which ensures safety events are reported and corrective action is taken to prevent future safety incidents.
The Sikorsky ASB is mandatory and so will be complied with by helicopter operators, worldwide. In summary, it requires operators to undertake:
-One-off inspections of the tail rotor and bearing assemblies before the next flight
-A specific check of Health and Usage Monitoring System (HUMS) data for each aircraft
As the global offshore helicopter safety association, HeliOffshore continues to enable the exchange of information and collaboration across the industry – with safety always our first priority. Please visit www.helioffshore.org for further updates.
On January 10, 2017, Sikorsky issued an Alert Service Bulletin (ASB 92-64-011) requiring inspections and health and usage monitoring system download and analysis on all S92A aircraft, worldwide. From Sikorsky:
“Sikorsky is working closely with our customer and investigative authorities to determine the root cause of the loss of tail rotor authority in the Dec. 28 rig landing incident. We have communicated additional guidance to S-92 operators regarding Health and Usage Monitoring System usage and will continue to provide information as it becomes available.
Jan 10 Update: Although the investigation into the Dec. 28 incident has not been completed, Sikorsky released an Alert Service Bulletin on Jan. 10 to define additional interim inspection requirements for the S-92 Tail Rotor Pitch Change Shaft. Those procedures include an off-aircraft check of the PCS bearing and that check must be done before next flight with some leeway for getting back to base.
Safety is our top priority, and we are committed to keeping our customers informed. We will further communicate findings if the investigation reveals any safety or airworthiness issues that affect the S-92 helicopter fleet.”
Jan 10 P.M. Update from Sikorsky:
“We anticipate that the majority of the fleet will have the initial inspection accomplished within the next 24-48 hours depending on their operational tempo. Many operators have already informed us that they have completed this inspection. From that point, there is a recurring inspection on a continual basis.”
HeliOffshore is enabling global collaboration to deliver a shared safety programme. As part of the programme, the HeliOffshore Reliability & Resilience workstream is working to:
- Enhance early diagnosis and resolution of potential failures e.g. through implementing best practices in use of health and usage monitoring systems and the development of Alternative Detection Methods;
- Improve equipment reliability, including fewer single point failures, and system(s) redundancy;
- Implement effective maintenance support;
- Reduce the operational impact of system failures; and,
- Enhance the feedback loop between operations and OEMs.