Boasting what is probably the longest gestation period of any aircraft in the history of flight, Leonardo’s AW609 is shortly expected to be granted certification. Gideon Ewers, Editor of RotorHub International, takes a look at the project’s backstory and ponders the tiltrotor’s future.
This article was originally published in the October/November 2023 edition of RotorHub International and has won “Best Rotorcraft / Vertical Flight Submission” at the 2024 Aerospace Media Awards.
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The history of the AW609
It’s hard to say when the idea of a tiltrotor aircraft first popped into the head of an aircraft engineer. It seems reasonable to assume the idea of a hybrid lift wing in cruise probably occurred to some engineer shortly after reading the news of the Wright Brothers’ first successful flights at Kitty Hawk.
A source of delay was that the US FAA had to decide how to certify and regulate the type for civil operations. All photo credits: Leonardo
It seems reasonable, but it’s also incorrect.
In fact, another pair of brothers, this time the Franco-Swiss pair Henri and Armand Dufaux, began work on their design “Convertible” in 1902, predating that famous day by more than a year.
The Dufaux brothers had not only begun their work before the Wrights; they filed their patent for their design before the maiden flights of both the Focke-Wulf Fw 61 and the Vought-Sikorsky VS-300 by nearly a decade.
Of course, there is a great deal of difference between coming up with a design and filing a patent and actually going out and flying. Thus it was that the best part of 20 years would elapse before work began on the first practical tiltrotor to fly – the Transcendental Model 1-G.
There had been some work carried out by Focke-Wulf and others during the Second World War, but it came to nothing in terms of a flying aircraft.
After some eight years of development, the 1-G made its maiden flight in 1954 – though sadly, it came to grief a year later, crashing into Virginia’s Chesapeake Bay, and was beaten to the first flight punch by the AW609’s ancestor, the Bell XV-3, which first flew in 1953. So began Bell’s dominance of the tiltrotor world.
Sure, there were other contenders, notably the LTV XC-142, but these were, in effect, research projects that began and stayed until their programme was completed. As an amusing sidebar, Westland (later Agusta Westland, later Leonardo Helicopters) exhibited its tiltrotor concepts, the We 01C and the We 028, at the 1968 Farnborough Airshow.
The same might be said of Bell’s XV-3, although that project was dusted off and revisited in 1972 with the NASA and US Army-funded XV-15 programme, which was certainly the grandparent, if not the parent of the AW609. Of course, if we are to look at the genetics of aircraft, the much beloved (by the US military) V-22 takes rather more after Pappy than the 609, at least cosmetically.
Nevertheless, the lineage is there, since the genesis of the 609 came from a desire by Bell and Boeing to parlay their hard-won knowledge created during the V-22 programme into a civilian product.
Airline partnerships and acquisitions
It is worth noting at this point that, according to filings made by Bell in 2011, there is no directly transferable technology from the V-22 in the AW609.
It is interesting to note. What is beyond debate is that these two aerospace giants took the view that the way forward for commercialising the lift cruise concept lay in smaller corporate, SAR, HEMS, and patrol roles rather than as a city-centre to city-centre regional airliner.
A lesson there for UAM/AAM developers, perhaps?
In any case, the nascent AW609 project was launched in 1996, although as a Bell/Boeing project, it wasn’t known as that then. Boeing decided to make its excuses and leave the project two years later and four years before the prototype made its first flight, to be replaced by Agusta. Thus it was that we get to the meat of our story and the first flight of the BA609 (as it was then known).
It’s here that the story enters one of its complex phases. After the first flight, progress on development wasn’t what could be described as Olympian. Bell had its mind and resources focused on other projects. Ultimately, frustration with that lack of progress forced Agusta Westland owner Finmeccanica (as Leonardo was then known) to buy out Bell’s interest in the project.
How much for remains the subject of debate, although, at the time, informed opinion among the cognoscenti of the aviation media thought the sum was “not a lot”.
So we arrive at the point in the story where the AW609 becomes the AW609.
Aviation industry disruptions
There can be no doubt that Leonardo’s pursuit of the certification and eventual commercialisation of the AW609 has been dogged.
Leonardo’s AW609, on the ground, preparing for a test run. All photo credits: Leonardo
First there were the storms to be weathered as the regulators set to work, and in particular delays while the US FAA decided how to certify and regulate the type for civil operations – perhaps another lesson from recent history for developers of eVTOLs. Arguably, funding shortfalls at the FAA have also had an impact on the timeline of this and other certification programmes.
Undoubtedly, the loss of a prototype in a 2015 crash also took its toll.
The continuing issues with the V-22s – most recently, of course, the tragic crash in Australia, have not helped matters, but it would be simplistic to point fingers at these two factors and say, “Ah ha, they are the reasons.” Let’s not forget that in 2002, certification and service entry were projected for 2007, by which time certification had slipped to 2011 and then to 2016 and 2017 for EASA and FAA certification, respectively. Then came Covid.
That said, it would be unwise to discount the fact that, as far as civil operations are concerned, the AW609 is an incredibly innovative aircraft that will come out of the box with capabilities like flight into known icing, pressurisation, and an operating envelope far beyond traditional vertical lift aircraft.
It’s also worth noting that during that period, Leonardo used the time to make a number of changes to the original design of the aircraft. The cabin is larger and increased in height, width and length – changes that make it comparable in size to a PC-12 or mid-size King Air. Leonardo also made changes to the cabin door configuration that improved the type’s suitability for EMS operations.
In any case, by the spring of this year at Heli-Expo in Atlanta, Leonardo briefed journalists that FAA certification would be completed by the end of this year, with service entry early next year. Clearly, the sands of time are running on that prediction, and at the time of writing, four months remain for it to be fulfilled. But it’s also true that test pilots from both the FAA and EASA have flown the test aircraft, the FAA has issued a standards certificate, and the certification ducks are beginning to move into alignment.
So it’s still possible that the FAA will provide Leonardo with an early Christmas present.
Pioneers in the tiltrotor aircraft industry
Leonardo points to the advanced state of the logistics side of the AW609’s development as an indicator of the company’s continued commitment to the type and its rapid commercialisation when certification is finally achieved.
There is already a full-flight simulator in operation at the company’s Philadelphia facility, where the first of the production aircraft are already on the line – including aircraft for launch customer Bristow.
So what of the commercialisation of the type? What the current order backlog is, Leonardo is keeping a closely guarded secret, but the unofficial figure bandied about by industry commentators is 60.
Of course, Bristow is known as one of those with order positions, and their first aircraft, the sixth off the line, will be the first example of the type not to be retained by Leonardo for further product testing and development.
As for how the type will be used by Bristow, the obvious suggestions are for offshore support and SAR operations – the two cornerstones of the company’s business – as well as to expand operations in other areas.
Bristow’s Programme Manager for AAM, and former V-22 pilot, Bryan Willows, said after his first flight in the type last year: “The AW609 is an important aircraft as Bristow helps advance vertical flight technology – just like we have for the past 70-plus years.”
Likewise, the other announced customer, Weststar Aviation, aims to explore the type’s capabilities with its operations in the Malaysian market.
Speaking at the announcement at the Langkawi Airshow in May, Weststar’s Group MD, Syed Azman Syed Ibrahim, said: “As Weststar continues to push the boundaries of innovation and operational excellence, we are excited to partner with Leonardo to introduce the AW609 tiltrotor in Malaysia.
“This groundbreaking aircraft will revolutionise our operational capabilities, providing us with a versatile platform to fulfil our various missions.
“We are proud to be the pioneer in bringing the world’s first multirole tiltrotor to Southeast Asia, and we look forward to demonstrating its exceptional capabilities to our present and potential clients.”
Interests in expansion and global advancements
Leonardo has also revealed that a private individual has placed an order for the type. Other rumoured buyers include a European-based high net worth individual as well as interest from customers in the military industry.
With the Leonardo AW609’s certification in the offing, Leonardo is now working on its next-generation civil tiltrotor. All photo credits: Leonardo
Looking at the type’s potential capability as a SAR or EMS platform, especially in parts of the world like Australia where distance is a factor, the AW609’s projected 270 kt cruise and 1,000 nm range could be a life-altering game changer.
In the corporate market the implications are obvious. Even though the 270 kt cruise may not be quite as fast as some of the similarly sized fixed-wing alternatives, the improvement in door-to-door travel times is significant and would negate the speed advantage of slightly faster turboprop alternatives on sector lengths up to the 609’s projected maximum cruise range of 1,000 nm.
Indeed, the ability to land closer to where the passenger wants to be may make for a compelling door-to-door travel time, even when competing with mid-size corporate jets. Leonardo says it believes there is a market for up to 700 aircraft.
What of the future? Leonardo is already working on its Next Generation Civil Tiltrotor (NGCTR). The development aircraft, which uses an AW609 fuselage, is intended to test a number of new technologies and concepts destined for future tiltrotor aircraft.
These include changes to the wing design and empennage, as well as rotor tilt actuation – not to mention a fly-by-wire control architecture. While that programme has taken some hits due to supply chain and other issues, the expectation is that it will make its first flight in 2024.
So it may be that rather than a culmination of nearly a century of tiltrotor development, the AW609 is actually the nexus to the future.
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