Offshore helicopter operators are continuing to battle serious fleet availability challenges on the Sikorsky S-92 that are “unprecedented in [their] severity and duration” and which oil and gas producers say pose “significant safety and operational risks”.
In October last year, the aviation subcommittee (ASC) of the International Association of Oil & Gas Producers (IOGP) issued a safety notice to members warning that a shortage of parts, particularly of main gearboxes, for the S-92 was leading operators to take “extraordinary actions” to keep fleets flying.
It called on IOGP members to waive punitive financial penalties for operators who were struggling to meet contracted aircraft availability levels. This, it said, would reduce the pressure felt by over-stretched maintenance departments and help head off what it saw as a growing safety risk.
At the time, it said 31 S-92s were grounded awaiting replacement gearboxes and warned that figure could top 60 airframes by the end of 2024.
Although Sikorsky promised the situation would ease throughout the year as additional manufacturing capability came on stream, the ASC says “the industry situation has not improved” and is also spreading to other offshore helicopter types.
“Among the aircraft operators, the shortage of critical spares is directly impacting their ability to meet customer demand, placing a significant strain on maintenance department resources and creating significant financial stress,” writes ASC chair Tony Cramp in an August update.
“This also impacts their capacity to invest to maintain the necessary safety and resilience.”
Cramp says helicopter operators have “reached out to the ASC once more” to seek “assistance to address what they view as a critical situation”.
Data provided for the June-July period by five of the largest operators – Bristow Group, CHC Helicopter, Cougar Helicopters, OHI and PHI – whose fleets represent 75% of offshore- and search and rescue (SAR)-roled S-92s, show a total of 27 examples grounded “primarily awaiting replacement main gearboxes (MGBs), but also other components”.
But as operators have had to resort to cannibalisation of helicopters to maintain fleet uptime “seven of those aircraft are now effectively in storage as parts donors, with no medium-term prospect of revenue service”, says the letter.
Cannibalisation, what the ASC calls “robbery action”, has “either remained high or for some time continued to increase on October 2023 levels for [the] S-92… and has also increased for some other types, albeit remaining at a lower level”.
In fact, one operator “reported 158 items robbed from a single aircraft”, the letter says.
Forecasted deliveries of MGBs “still run beyond the end of 2024”, it says, and the average time required for major inspections also remains elevated – at 70 days: around double pre-crisis levels.
Although the IOGP’s October 2023 warning that 60-plus S-92s could be grounded by the end of this year appears unlikely to come to pass, operators see the situation as having merely stabilised rather than shown drastic improvement.
“The situation has really not improved, although it’s not got any worse either,” says one S-92 operator, who asked not to be identified. “It has generally stabilised at a pretty disappointing level for now. As an industry we are still experiencing some very extended delays on S-92 components.”
Although the operator says supply chain problems have spread to other components and other types – windshields for Leonardo Helicopters AW189s, for example – “we don’t have other helicopter types where we have more than 30 aircraft down globally because they don’t have gearboxes.
“The situation on the S-92 really is unique and unprecedented in its severity and duration.”
Another operator uses more diplomatic language in its assessment, but the underlying tension is still clear. While admitting “supply chain constraints remain an ongoing issue” it is “confident” the situation will “soon recover”.
“All our OEM partners are actively addressing issues, including creating technical solutions for particular pain points, such as gearbox components,” it says.
“Sikorsky has worked hard to create solutions over the last 12 months and good progress has been made. We see a long-future for the S-92. Challenges do, however, remain.”
Back in October, Sikorsky pinned the difficulties on the lingering effects on the supply chain from the Covid-19 pandemic, and an offshore industry that had rebounded much faster than predicted, causing demand for parts to outstrip supply.
The airframer said it had invested tens of millions of dollars in its supply chain to alleviate the problem but cautioned that results would not be immediate.
“Our impression is that the team at Sikorsky is working earnestly to address these issues, but it is hard to turn this ship around,” says one operator, noting that timelines that have repeatedly slipped.
Sikorsky is still targeting the fourth quarter to achieve a step-change in MGB availability, but the promise is viewed with scepticism by that operator. “I want to believe them – I hope they are right. But we have been given a number of timelines over the last couple of years and they have yet to meet any of them.”
Nonetheless, Sikorsky insists its efforts to recover the situation are bearing fruit: it delivered 39 MGBs in 2023 “and is on track for a 25% improvement of MGB deliveries in 2024” – at the time of writing, it was due to match the previous year’s delivery total.
“More importantly, we have been working on the life limits of the MGB housing which are a driver to the need for replacements,” says Leon Silva, vice-president of global commercial military systems at Sikorsky. He anticipates that the life-limit increase will be certified in September. Sikorsky did not immediately clarify the new limit, however.
“That change in September will allow many of the MGBs to stay on-aircraft longer and dramatically reduce the overall replacement need for the fleet,” says Silva.
“This combined increase in hours along with the increase in MGB production numbers will allow us to close the gap in MGBs even faster than we had originally planned.
“We continue to produce MGBs to support the projected fleet demands over the coming years and stand by our commitment to recover to normal operations by the end of this year.”
Leonardo Helicopters, whose AW139 and AW189 are also widely used in the oil and gas sector, says operational availability and parts supply for both types has improved year on year. “Operational availability was nearing 80% last year and is now exceeding this percentage,” it says.
Airbus Helicopters did not respond to questions about availability levels for the super-medium H175.
But as the ASC pointed out in its original safety notice, the problem for operators is deeper than simply dealing with aircraft availability: pressure to meet contracted flight rates and avoid the financial penalties still being levied by some oil producers continues to create a serious safety risk.
Although the ASC praises operators for continuing to deliver crew-change services despite the continuing problems – the industry “by its nature, will default to meeting customer needs”, it says – it cautions that although risk-management systems “remain effective”, the pressures being felt by businesses “introduce the potential for safety risk”.
Assurance activity “indicates that they are under financial and operational strain and the conditions for human factors-related incidents are high”, it says.
The safety update warns that the situation is being made worse by a “significant number” of the IOGP’s members “applying punitive financial penalties” on operators for failing to meet contracted aircraft availability levels, despite shortfalls being caused by “factors beyond [their] control”.
As a result, the ASC has reiterated its call for members to exercise restraint when contemplating those penalties as their “contracting actions have a direct and significant impact on our operators, potentially either alleviating or exacerbating the industry-wide pressures”, it says.
Operators also emphasise that mixed picture. “On the one hand, it is encouraging that most IOGP members have chosen not to levy penalties, [but] there are a couple of large oil companies that have continued to levy those penalties against IOGP advice,” says one.
Another points out that “penalties are being applied, to varying degrees” and says it “clearly communicates whether challenges to meet flying hours are due to part-related issues out of our control or operational challenges we are experiencing”, it says.
“Our long-term customers recognise how part-related challenges are causing issues. They are receptive to solutions we offer and don’t apply penalties. Others will penalise us regardless.”
It stresses that customers need to “recognise the importance of long-term investments in sustaining operations”, adding: “Short-term contracts make the industry as a whole less attractive – from an investment perspective, and from a talent perspective.
“And punitive application of penalties limits cash available to operators to invest in our services, assets and people.”
While the MGB issue should eventually be resolved in the short- or medium-term, the longer-term outlook for the S-92 is less clear.
Production is currently at a low rate – predominantly addressing the VIP market – although it is unclear where the helicopters are being built, with Sikorsky having sold off the Coatesville, Pennsylvania plant where it formerly assembled the heavy-twin.
With the last offshore-roled example delivered in 2019, forecasts suggest that the segment of the oil and gas market serviced by the S-92 will continue to contract as double-digit annual retirements kick in from later this decade and as more super-medium types such as the AW189 and H175 enter the market.
In a June investor presentation, Bristow Group highlighted data showing that, based on a 25-year useful life assumption, S-92 offshore retirements would ramp up from the start of the next decade, averaging at 16 helicopters annually over the 11 years from 2030 to 2040.
Nonetheless, the S-92 will likely continue to attract orders for VIP/head-of-state operations – aided by its adoption by the USA as the VH-92A Patriot presidential transport – and for the SAR market.
But whether offshore operators will return for new examples remains an open question. “I think it is extremely difficult to envision wanting to make new investment in an aircraft for which you have fundamentally lost confidence and support,” says one.
“All S-92 operators around the world have been forced to have so many difficult conversations with our customers over the last couple of years. Customers want alternatives; they want to derisk their exposure to the S-92 as well.”
That said, Sikorsky bristles at the suggestion that the S-92 is anything other than a live programme: several examples were delivered in 2023 and there are “more planned in 2024”.
“We see a healthy demand signal across the various mission segments – offshore, head of state/VIP, search and rescue and utility – and have plans to increase production capacity should that demand become firm,” says Silva.
