Vertical-lift pioneer Sikorsky is facing mixed fortunes at the moment.
On the one hand, the company known for building the world’s first practical helicopter has a years-long backlog for its H-60 family of rotorcraft, which is among the most popular helicopters in the world with over 5,000 examples delivered.
However, despite the ongoing success of the H-60 series, and Sikorsky’s long-serving line of CH-53 heavy-lift helicopters, now in its K-model guise, the company is currently staring down a period of uncertainty without a clean-sheet aircraft under contract.
Sikorsky in 2023 lost its bid to build the US Army’s Future Long-Range Assault Aircraft (FLRAA) next-generation, Black Hawk-replacing troop carrier – and a subsequent appeal – to rival Bell’s V-280 tiltrotor design. Then in February, the army cancelled a separate programme – the Future Armed Reconnaissance Aircraft, or FARA – to develop a new long-range scout helicopter, for which Sikorsky was also vying.
That double-whammy has left the iconic manufacturer without the long-term certainty of a new design contract.
“Engineering work is a challenge for us right now,” said Sikorsky president Paul Lemmo, who spoke with FlightGlobal at the 2024 Army Aviation Association of America conference in Denver, Colorado on 25 April.
While the FARA cancellation did see some 400 positions eliminated at Sikorsky, the company’s challenge is at least partially offset by a boom in orders for existing aircraft.
“We’re fortunate to probably have one of the largest production backlogs in the rotary-wing industry,” says Lemmo. “So production wise, we’re very stable.
“We’ve got a lot of aircraft to go build,” he adds.
Those will come primarily in the form of UH-60 Black Hawks, particularly for the US Army. The service announced it will purchase additional aircraft from Sikorsky as part of the strategic reorientation of its aviation fleet that resulted in the demise of FARA.
Overseas interest in the Black Hawk has also been robust in recent years, including from Australia, Croatia, Greece and Romania. The naval MH-60R Seahawk has also proven popular abroad, with orders from Norway, South Korea and Spain.
The MH-60T Jayhawk variant is also providing some new business, with Sikorsky in the process of overhauling existing airframes in the US Coast Guard inventory and the potential for new-build orders to follow.
Sikorsky is also moving toward full-rate production on the CH-53K King Stallion, currently in service with the US Marine Corps and also ordered by Israel.
All that has given Sikorsky’s factory workers plenty to do on the floor of its main assembly site in Stratford, Connecticut. However, the engineers upstairs now find themselves without a new aircraft to design.
“We’re coming off of three programmes that we had in development at the same time,” Lemmo says: the CH-53K; the HH-60W – the US Air Force’s new Combat Rescue Helicopter; and the VH-92A presidential helicopter replacement for the White House.
“They’ve come down significantly over the last few years and, and so the lack of a new start is a challenge for us,” Lemmo notes.
Although currently limited, opportunities to develop a new clean-sheet aircraft do exist. A consortium of six NATO members in Europe plan to develop a so-called Next Generation Rotorcraft Capability, for which Sikorsky intends to compete.
Lemmo says the company will submit an offer for the current concept design stage based on Sikorsky’s proprietary X2 compound coaxial technology, which formed the basis for its FLRAA and FARA bids.
“We’re working with a lot of customers to see what engineering work we can do,” Lemmo says.
While a new-design aircraft is the goal, other mitigating options exist as well.
“Certainly, I’d say a robust modernisation programme can help,” Lemmo adds. “It doesn’t have to be a completely new platform.”
The US Army already has a UH-60 modernisation plan in the works. That programme includes an entirely new engine – the GE Aerospace T901 Improved Turbine Engine – which Sikorsky is already testing in West Palm Beach, Florida.
Part of the challenge in securing a new design contract comes down to simple economics. Developing an aircraft with generational improvements over existing models – such as Sikorsky’s X2 line or Bell’s V-280 – comes with a hefty price tag.
Such aircraft will not be suitable for all operators, according to Lemmo, particularly those with more limited budgets.
“You can’t afford to buy thousands of platforms that are going to have the kind of performance, speed and range, and be vertical take-off, because that’s what adds a lot of cost,” he notes.
“So we believe that there’s always going to be a mission for something like the [Black] Hawk on the battlefield to fly alongside a V-280 or whatever high-speed platform there is,” Lemmo adds.
The US Army now plans to fly the Black Hawk into the 2050s and 2060s, alongside its new fleet of FLRAA rotorcraft, which will be fielded operationally around 2030.
That fundamental reality is now forcing Sikorsky to search for a third way to support future business, including new hybrid-electric propulsion systems and uncrewed aircraft.
“We are absolutely looking into UAVs,” Lemmo says, noting the company is focusing within its vertical-lift area of expertise.
The current focus of that effort is a novel aircraft design Sikorsky calls the rotor-blown-wing.
Lemmo describes the concept as a tail-sitting flying wing that uses rotors, rather than turbine engines to generate thrust and lift. Rotors blow air over the tail-sitting wing for vertical launch, with the entire aircraft subsequently rotating for horizontal flight.
The description appears to match a Sikorsky concept that was funded by the Defense Advanced Research Projects Agency (DARPA) in 2013. The $130 million project aimed to develop a vertical-lift aircraft weighing 4,540-5,440kg (10,000-12,000lb) and capable of flying at sustained speeds of between 300-400kt (555-740km/h), according to DARPA.
The radical design was intended to address the aerodynamic phenomenon of retreating blade stall, which limits the speed of conventional helicopters to around 180kt.
Lemmo says Sikorsky has been flying its rotor-blown-wing prototype for the past 18 months, with “a lot of interest from various customers”, whom he declines to name.
While civil aviation is not currently a major focus of Sikorsky’s business, Lemmo says that will no longer be the case going forward.
“Anything that we’re doing at this stage, our minds are on dual use: both civilian and military,” he notes.
The company also unveiled its vision for a so-called “tiltwing” vertical take-off and landing civil aircraft in February at the Heli-Expo trade show in Anaheim, California.
Called Hex, the hybrid-electric concept will incorporate Sikorsky’s Matrix technology enabling it to eventually fly autonomously. Sikorsky and GE Aerospace are finalising designs for a hybrid-electric systems testbed powered by a 600kW electric motor, with flights of a sub-scale proof-of-concept aircraft having already taken place.
Lemmo says Sikorsky hopes to assemble the full Hex prototype between 2026 and 2027, with first flight following shortly after.
