Offshore helicopter operators continue to grapple with an ongoing shortage of Sikorsky S-92 spare parts, particularly main gearboxes, leading to unprecedented fleet availability challenges and concerns about safety and operational risks.
The International Association of Oil & Gas Producers (IOGP) Aviation Subcommittee (ASC) issued a safety notice in October 2023, warning members about the severe shortage. This shortage was impacting operators' ability to meet contracted aircraft availability levels, placing a significant strain on maintenance departments and causing financial difficulties.
The ASC urged IOGP members to waive punitive financial penalties for operators struggling to meet their contractual obligations, recognising the pressure this would ease on strained maintenance resources and mitigate growing safety risks.
Initially, 31 S-92s were grounded, awaiting replacement gearboxes. The ASC predicted that this number could reach 60 by the end of 2024. While Sikorsky promised an improvement in the situation as additional manufacturing capacity came online, the ASC reports that the industry situation has not improved and is now affecting other offshore helicopter types.
Data provided by five major operators - Bristow Group, CHC Helicopter, Cougar Helicopters, OHI and PHI, representing 75% of the S-92 fleet - shows 27 helicopters grounded, primarily due to a lack of replacement main gearboxes. This has forced operators to resort to cannibalisation, with seven aircraft effectively in storage as parts donors, with no immediate prospect of returning to service.
The ASC highlights that the average time required for major inspections remains significantly elevated at 70 days, roughly double the pre-crisis level.
Despite the initial prediction of over 60 grounded aircraft by the end of 2023, the situation seems to have stabilised rather than improved drastically. While the supply chain issues have spread to other components and helicopter types, the S-92 shortage remains unique and unprecedented in its severity and duration.
Sikorsky has attributed the challenges to lingering effects from the COVID-19 pandemic and a faster-than-expected rebound in the offshore industry, creating a mismatch between demand and supply. The airframer has invested significantly in its supply chain but acknowledges that results will not be immediate.
Sikorsky aims to achieve a substantial improvement in main gearbox availability by the end of 2023, but some operators remain sceptical, citing repeated delays in previously promised timelines. The company has increased production and is working to extend the life limits of the gearboxes, but the impact of these efforts is yet to be fully realised.
Leonardo Helicopters reports that operational availability and parts supply for its AW139 and AW189 models have improved year-on-year. Airbus Helicopters did not respond to inquiries about the availability of the H175.
The ASC highlights the deeper problem beyond aircraft availability: the pressure on operators to meet contracted flight rates and avoid financial penalties imposed by some oil producers, which exacerbates safety risks.
While praising operators for maintaining crew-change services despite the ongoing challenges, the ASC warns of the potential for safety risks due to financial and operational pressures, leading to a high risk of human factors-related incidents.
The ASC urges IOGP members to exercise restraint when considering penalties for operators as these actions can further exacerbate industry-wide pressures. Operators, while acknowledging the efforts of some oil producers, note that a few continue to impose penalties despite the issues being beyond their control.
The long-term outlook for the S-92 remains uncertain. Production is currently at a low rate, primarily addressing the VIP market. Forecasts suggest that the offshore segment of the S-92 market will continue to shrink as retirements increase and super-medium helicopters like the AW189 and H175 gain popularity.
While the S-92 will likely remain relevant in the VIP/head-of-state and SAR markets, its future in the offshore sector is less clear. Operators express concerns about confidence in the aircraft and the potential for alternative options.
Sikorsky, however, maintains that the S-92 is a live programme with ongoing production and a healthy demand across various sectors. The company plans to increase production capacity if demand solidifies.
The S-92 spare parts crisis continues to pose a significant challenge for the offshore helicopter industry. While the situation appears to have stabilised, further improvements are needed to alleviate the pressure on operators and ensure the safety of offshore operations. The long-term future of the S-92 remains uncertain, and it will be crucial for operators and manufacturers to work collaboratively to address these challenges.
