The AW609 tiltrotor programme has undertaken its first successful ship trial, supported by the Italian Navy.
From 3-12 April 2024, the AW609 AC4 aircraft, in its final production configuration, conducted demonstration trials at the Maristaer Grottaglie Naval Base.
The trials included take-offs and landings on the Italian aircraft carrier ITS Cavour, demonstrating the tiltrotor’s approach, stable deck landing, and touchdown capabilities.
The trials were preceded by a test campaign using the AW609 development/engineering simulator in Cascina Costa. This digital twin application provided a preliminary assessment of the activities and manoeuvres, benefiting capability development, time reduction, safety, and sustainability say the firm.
The aircraft performed deck landing and take-off procedures in over 15 different conditions, including various wind conditions.
The trials are part of ongoing activities by a joint working group established in 2022, comprising Leonardo, the Italian Navy, the Italian Army, and Guardia di Finanza (Italy’s Customs Police). The group aims to evaluate the potential of tiltrotor technologies as complementary capabilities to existing assets in government services.
“Fast rotorcraft technologies continue to be core to our forward-looking capability development and value proposition in the vertical lift domain, which has been extensively demonstrated by the progress on the AW609 tiltrotor programme. The recent ship trials in Italy, with the strong support of the Italian Navy, represent an important step towards the development of government applications,” said Lorenzo Mariani, Co-General Manager of Leonardo.
“The success of these trials set a major capability demonstration milestone to show the unique advantages of tiltrotors, particularly the AW609. This experience provides an important opportunity to appreciate benefits that can truly revolutionise a range of missions or even open new operational possibilities,” added Gian Piero Cutillo, Managing Director of Leonardo Helicopters.
Following the ship trials, Leonardo will begin a detailed evaluation and analysis of the collected data. This will allow for potential follow-on trials to refine approaches and enhance the platform for naval and embarked environments.
Didn’t even realise there was another tilt rotor being worked on. Intresting, if not rather small fuselage for any naval application.
Perfect for QE’s then…
For what though?
It’s a 7000kg machine with a payload of 2500kgs and 6-9 passengers..which is better than the internal load of a black hawk or Seahawk range medium rotor…it also has a 900mile range at full load ( twice the range of a medium rotor), goes around 100miles an hour faster than a medium rotor and as a sensor platform has a ceiling of 25,000 feet or over twice that of any medium rotor, it’s also a pressured cabin for crew being able to function…
its pretty much superior in every way to the same weight class of rotor ( black hawk, Seahawk size)…
The main problem is that it was a joint bell AW project and after they split and Bell kept the military license…basically the usual US screw over.
OK but I think what most are asking is whether it could fulfill roles like AEW or cargi delivery but it seems a little small, ignoring the other issues with tilt rotors.
Well it’s got greater internal space than a sea hawk, can carry 12 people or 2500kgs of load…so the answer is yes.
There’s no AEW version of a Sea hawk, better question, how does it compare to a Merlin.
There’s a bit of a space issue when you look at pictures of the inside
https://www.navylookout.com/first-crowsnest-equipped-airborne-surveillance-and-control-helicopter-goes-into-service-with-the-royal-navy/
There’s a picture in there of the crownest equipment
https://www.agusta.com/range/AW609-TiltRotor?lang=en
And in here are pictures of the actual cabin size. It may be long enough to fit more people than a sea hawk, doesn’t make it wide or tall enough for much equipment
Not really as there is no need to compare lift capability ..Merlin is closer to a heavy lift rotor than a medium lift…the AEW offer is on Merlin because Merlin is the only naval rotor available to the RN that’s not really light weight…AEW sensors don’t need the full lift capability of Merlin….If you look at searchwater radar it only weighed in at 200kg…you can get a full fat 3D S band air search radar on a ship for 800kgs so the 2500kg load of a AW609 is plenty for almost any airborne radar the RN could need.
so if lift capacity is not an issue..essentially both Merlin and AW609 can lift it…then the comparison should be ceiling and the AW609 has over double the ceiling, crew fatigue and the AW609 has a pressurised far better cabin, range AW609 has almost double the range, speed and AW609 has 30% more speed…it would be a profoundly better AEW platform than Merlin…but as I stated it’s all academic because there will never likely be one and even if there was we could not afford it.
Weight isn’t the issue, actual shape of the cabin is, plus the rotors don’t fold
But yes, unlikey either way.
It will never happen. I believe to get the contract to develop it they had to sign to say no military use? Im sure I heard that here a couple of years ago
I read the same – Bell handed the project over to Augusta on that basis.
Hi Andy, I did say it would never happen as the licensing agreement is that the AW609 will only be a civil design…as years ago it was the Bell Augusta 609 and when Augusta bought out Bell, as the US does it put a protection in the licence of military usage.
Not necessarily that simple… it flies fast and far and has a decent payload weight, will definitely carry people and small cargo but can it do the jobs it might be needed to do (what is the requirement)?
It is likely far less efficient than a regular RW at slow speed and in the hover so you would not want to use it for dipping sonar or anything requiring prolonged low speed flight profiles unless the ability to respond at range outweighs the penalty.
not sure it would easily take a door gun or allow for an air sniper so may not be great for boarding overwatch and fire support (assuming it can fly the correct profile to support that). Could you get troops in and out quickly enough (with full kit) in ship to shore ops (even before you ask about fast roping etc)?
From a practicality perspective, it’s door is not very big, so can it take the cargo you need it to carry (based on size rather than weight)? Can you easily switch it between roles (eg putting in a mission desk)? Could you get casualties in and out and easily configure the cabin for medical flights?
Will it fit the carrier lifts? It certainly wont fit in a frigate hanger so you have to have both tilt rotor and conventional hence will have to pay for two fleets of aircraft not one common one (and operational cost of a fleet dwarfs the upfront purchase cost). Is it worth the cost even if it is best for the jobs it does do?
The mechanical system is complex, will it be as reliable and available as a standard RW?
What happens to the performance once you add possible missions systems like secure Comms, external sensors, defensive aids, weapons, armour, self sealing fuel tanks, is the structure strong enough to allow for these to be fitted and still operate pressurised or will it need strengthening?
No idea about the answers to the above but headline performance alone will not tell you if it is a good choice once you go beyond too trumps. You have to know the actual requirement and work out if it can meet it and be better than the alternatives when looking at everything.
supposed to have a much smoother ride for occupants than a helicopter and range gives possibility of rescuing a downed pilot
There is no folding the wing, so this is not going to be in a ship.
These are generic trials and eventually for a land to ship supply operation.
no unfortunately the AW609 cannot be used for military applications..bell hold the license for the military version of this particular rotor family. I suspect the Italians are looking to get around that with paramilitary functions such as coastguard…which would get around the licence issue.
I thought they gave up on AW609 ages ago.
Same here Jim, it seems to have been rumbling on for decades…
Obviously, too big for the average carrier..
It’s not small, but it’s much smaller than the V-22 and V-280. It’s not far off the dimensions of a Merlin.
Possible AEWC platform. Probably can get up higher, go faster and better range?
Ceiling is 25,000 feet or double that of a medium rotor, range is 900 miles at full load..almost double that of a medium rotor, speed is 310mph around 100 miles an hour more than a medium rotor…it’s also got a pressured cabin for crew comfort and work…it would make a profoundly goos sensor platform for the carriers…trouble is AW don’t own the license to make a military version, Bell do…and have never bothered..although they are now wanting to develop the V280.and I imaging AW own some of the preparatory stuff Bell would like to use..so you many see AW and Bell negotiating hard…
Merlin is a much bigger beast than you think. AW609 has a far smaller unfolded footprint than a Merlin.
Dimensions on landing (width by length, rotors turning)
Chinook: 18m x 30.2m (544m²)
Merlin: 18.6m x 22.8m (424m²)
V-22: 25.78m x 15.4m (397m²)
V-280: 24.93m x 15.4m (384m²)
AW609: 18.3m x 13.4m (245m²)
Wildcat: 12.8m x 15.24m (195m²)
For anyone thinking about possible UK applications from what I understand all tilt rotor’s are still complex and expensive to buy/operate.
With our budget better to pursue drone options for tanker, COD and AEW roles and stick with helo’s for commando insertion.
And if we really, really want a tilt rotor eventually then I’d rather we looked at a licence built version of the 280 Valour in the 2030’s.
I would agree, the innate problem with the AW 609 is that it tilts the whole engine, this was seen as a serious problem in the Osprey and as such the Valor only tilts the prop/forward nacelle itself, which gives a better and safer aerodynamic configuration and saves weight.
Absolutely, assuming Valor doesn’t get canned, let Uncle Sam work out the gremlins, get it into service and buy in the 2036/8 timeframe when it’s matured.
The primary problem with tilting the entire mechanism for the Army and the Marines is egress. They can’t barrel out of the side doors like they are used to. The uncrewed V-247 will also rotate the entire engine nacelle (and a chunk of wing to boot).
It’s was one of the design requirements for the Valor. The wing is 8 ft above ground level, plus the engine is kept horizontal on the wing tip. Which means the exhaust is not blasting a hole in the ground and creating a dust storm and throwing stones everywhere. The sliding side door has a bigger area than the Blackhawks, again to help ingress/egress.
Yes probably have to wait for tilt though a great synergy with f35 b carrier operations
My nephew is a master sergeant in the US airforce he tells me if they deploy three ospreys they need a fourth full of spares
Agree. A small ASA radar fitted to a drone with long endurance would be better for AWACS role. Then networked into a carrier battle groups air wing and screening destroyers and frigates.
The perennial problem will be funding an AWACs drone but the benefit of removing Crowsnest from the tasking of our Merlin fleet will be more Merlin available for ASW role, for which they are desperately needed and too few in number.
Having a relatively small drone such as a MQ9 as the AEW platform, significantly compromises the purpose of AEW. To detect threats as far away as possible you need a decent radar. Yes you could use an X-band radar as per Crowsnest (Serchwater 2000). But you are constrained by physics, as X-band is more effected by atmospheric absorption. Which means its range is heavily tied to how much transmit power it can produce. Hence why you see most X-band airborne radars with a range of around 200 to 250km. Which is also conditional on the target and amount of energy being reflected back to the receiver. So for a smallish sea skimming cruise missile, it might only detect it 100km away.
Traditionally for longer range AEW, the majority of platforms use L or S band radars (e.g. Wedgetail and Erieye), as these frequency bands are less affected by absorption from the atmosphere. For a relative low power output, they can produce a fairly long range detection. But to be effective, the antenna must match the wavelength, otherwise the radar’s efficiency is significantly affected. Which means it wont be small. To be brutally honest the antenna on Hawkeye and Erieye are a compromise. As they aren’t shaped for maximum efficiency. Whereas the Wedgetail MESA array is rectangular in shape. Which provides a more circular and narrower beam pattern.
If we look at the smaller Erieye antenna rather than the Wedgetail’s, that operates in the S-band (Freq = 2 to 4GHz or Wavelength = 15cm to 7.5cm), it has a detection range of around 450km. The antenna array sits on top of an aircraft’s fuselage housed in a 29′ 6.3″ (9m) long box and weighs 1985lbs (900kg). Then there is the back end signal processing of the radar, which needs to be housed.
This negates drones in the MQ9 class, as its fuselage (at 11m long) is too small to carry the antenna. Plus I’m pretty certain it wont have the electrical generating power to supply the antenna, let alone any onboard signal processing. The Eurodrone at 16m long is possibly better suited. Even then the antenna may impinge over the satcom antenna. Though with a 30m wingspan (MQ9 is 20m), it may be too wide for operating from the QE’s deck.
To put things in perspective, you will need 3 X-band radar carrying drones to cover a similar area as one Erieye. It also means that a Su35 carrying a Rh37 (150 to 400km range depending on variant). Will be capable of launching the missile at the AEW drone, before the drone can detect the aircraft. Whereas, Erieye will detect the Su35 before it can get into range to release the weapon. But if linked to a F35 or T45, it will have more time to coordinate the shooting down of the Rh37.
I’m just going to put this out there for your enjoyment and something to ponder on.
Go onto a search engine, stick in “Fairy Rotodyne” select video and just go oh.
One just has to wonder what the hell coukd be done with modern engines and materials and the engineering principles are way simpler.
IMHO the idea of tilting the entire engine and rotor assembly from lift to propulsion just looks wrong.
So why bother if you can just use an unpowered Gyrotor for lift when in forward motion and bleed jets at the rotor tips for hover, liftoff and landing
And we know a hell of a lot about gas flow, and efflux silencing these days.
OK I’m just putting my straight jacket on and going for a lie down. But god does that look like an elegant solution to my eyes.
I think this is an excellent take. As I say above newer designs (this one goes way back, they just can’t let it go) don’t tilt the whole engine it’s too problematical certainly as you go bigger.
I am convinced a while back I read somewhere (possibly on New Atlas but finding older articles reliably is not easy there) that a modern take on the Rotodyne is being conceptually worked on due to ongoing research and development around e-Copters and the like has made the concept far more feasible and yes bleed jets potentially quieter. But that latter or an alternative will be the secret of any potential success I think.
The Fairy Rotordyne style of convertiplane has a number of significant advantage over a tilt rotor, such as the Osprey, Valort or AW609.
Primarily the rotor blades can be correctly sized to match the aircraft’s predicted max all up weight. Which means loading on the disc can be much lower and therefore more efficient.
Secondly using only one rotor disc allows it to be placed centrally. But also allows it to be placed high above a main wing. On something like the Osprey, the gearbox and prop-rotors have a finite height above the wing when in the vertical position. This is because the drive shaft can’t be extended too far from the gearbox. As it will have a substantial load placed on it when moving from horizontal to vertical.
With the Rotordyne the main shaft is fixed vertically, so the load paths are easier to manage. The height of the rotor blades above the wing is very important. As the downwash (air being pushed down) gets interfered with by the closeness of the wing. Which reduces lift in the hover. The Osprey tries to mitigate this by reducing its wing area, by having large trailing edge flaps, that drop almost straight down, when the aircraft’s in the hover. The Rotordyne’s rotor disc is high above the wing. It will still interfere, but not to the same extent.
Compared to a normal helicopter. The Rotordyne in forward flight over 50knots is an autogyro. Where the main rotor is unpowered. It is spun by the advancing air impinging on the main rotor blades. Which means there’s no torque reaction, so it doesn’t need a tail rotor to counteract the torque like a normal helicopter.
Because the blades are turning at near the local airspeed. The blade tip speed is significantly lower and not entering the dangerous transonic zone. Therefore they can still generate lift if the aircraft doing 300knots. Unfortunately you will still get the advancing side of the rotor disc generating more lift the faster it goes than the retreating side. Which will cause the aircraft to roll if not corrected.
A modern version of the Rotordyne will be more than capable of reaching 300knots.
The noise issue with the tip jets was solved by Fairy, by designing a diffuser for the jet’s exhaust. This dropped the noise from around 113dBs to about 95dB. Which is similar to a normal helicopter. There is a cautionary tale regarding the Rotordyne. The tip jets robbed power from the Mamba turboprops. So much so that if emergency power was called for, the marching for error was critical. Westlands who took over the project when Fairy was merged. We’re looking at fitting a pair of dedicated smal turbojets for powering the tip jet compressors. But when the Government pulled the plug. The trial didn’t go ahead and the aircraft was scrapped.
As a concept though the Rotordyne is still valid. As it has a better performance in the hover than a tilt rotor. Yet can potentially travel at a similar speed and altitude.
The rotodyne was scrapped because of the noise level generated by the rotor jets. For an aircraft intended to move passengers between city centres, this was unacceptable. I recall that sound reduction was achieved but by then the government had cut the funding.
For purely military use, the noise level, only occuring briefly during lift off and landing, might not matter so much. The design does look more elegant then the rather Heath Robinson tilt rotors.
Old saying if it looks right then most of the time it is. As I say with modern materials and engine tech it should be way quieter and efficient.
I actually built an Airfix 1/72 model kit of this when I were a lad 🤔 I just thought it was just so Thunderbirds !
Surely with modern quietening techniques (like the feathering on jet engines) and materials it would be possible to make a significantly quieter Rotodyne?
I imagine it would be very useful as a Chinook/Osprey competitor, able to travel very fast and quietly at low altitudes and then unload a load of troops/jeeps by landing vertically.
Realistically a helicopter landing is going to be spotted for miles anyway and the risk of attack on the ground is not great with only 5 minutes or less spent unloading or loading, but being able to escape or enter twice as fast as much more useful.
Could also imagine a naval use (not sure about folding rotors with the jet pipes) as a Commando Merlin/ navally deployed Chinook replacement.
ASW would probably be a bit harder, don’t know about hover efficiency.
I would see it as perfect for carrier on board delivery and also for replacing the Merlin baggers for air radar coverage. Also now we have lost Hercs, be good for Special forces insertion. No idea what the range was on this and how it compares v chinooks.
It’s hard to compare the Rotodyne with modern helis because of advances in e.g. aerodynamic modelling, materials etc. My intuition says that it would be better than a Chinook; you have the same number of engines but they produce more sideways thrust and power a single larger rotor.
A small one could perhaps have the engine at the back to produce an aircraft like the Sikorsky Raider but with the autogyro and tip jet abilities. That would be great for special forces because it’s quiet in transit and much faster and more efficient than a heli.
I don’t think another rotary AEW is a good idea, that should all be drones now. I see it as replacing anything large helis and small planes do now but better.
The Rotordyne’s hover efficiency is the same as a standard helicopter.
The tip jets are feed “cool” pressurized air and fuel through pipes. At the rotor hub, these were flexible. As the blade needed to flap from aerodynamic loads. So in theory the blades could be folded.
The convertiplane design can be scaled up or down to suit the need.
Oh, the tip jets were actually powered?
I was under the impression that they were just redirected bleed air from the engines in the manner of the Harrier hover controls. That’s more complicated than I thought.
A problem with folding would be the wings with engines on.
Could the same effect be achieved by using a engine at the back in the manner of the Sikorsky Defiant? You could then use folding wings which could also be longer and more efficient.
HI SB, yep think of them in the same function as an afterburner. Where the fuel is injected in to the pressurised airstream and ignited. I did read that on one of the versions it included a fixed shaped compressor similar to a ramjet to aid combustion. This is why they were soo loud.
Fairy had developed and tested at their White Waltham site a number of exhaust diffusers, that reduced the noise by around 20dBs. Sadly by the time of the reports being finalised, the Government had pulled the plug.
If you go to the helicopter museum at Weston Super Mare. They have a number of parts from the Trials Rotordyne including a fuselage section, rotor mast and the end of a blade with a tip jet. If I remember correctly they had one of the final prototype diffusers as well.
The Rotordyne was pretty tall at 22ft 2in (6.76m) to the top of the rotor according to Wiki. By comparison a Chinook is 18ft 11in (5.77m). Not sure if this would be too tall for the QE’s hangar. But I’m sure a modern version would be designed to fit the hangar if that is one of the requirements.
The Rotordyne used for trials had folding tail fins. This was due to the metal rotor blades drooping down when at rest. There was I presume a fear that they would strike the tail fins when slowing down or speeding up. A modern version would probably have at least a five bladed or preferably a 7 bladed rotor head, which means the blades can be made shorter to have a comparable surface area. They would also be composite made, which makes them significantly stiffer, so they shouldn’t droop as much. However, you would still need to fold the main wing. Which would be similar to the Hawkeye’s, where the wing folds after the engine towards the wing tip. Folding the blades would be also be just as doable. As its the wing tips folding, they could fold down. So when the aircraft is in the hover, this will reduce the wing’s surface area and lessen the interference it causes from the downwash.
Technically you could use a Rotordyne concept with a single pusher propeller on the tail, similar to the Defiant’s. However, like the Harrier you would have to use engine bleed, bypass or exhaust gases in the tail and perhaps the nose, directed left and right to control yaw when in the hover.
If only the MoD and Leonardo had the balls to develop a new modern version of the Rotordyne. They could easily build an aircraft to rival the Chinook in lift capacity (11 to 12t), possibly even the CH53K King Stallion (15 to 16t). But also have a similar or better speed than the Osprey. It would definitely upset Boeing, who have ring fenced the heavy lift market. Basically having a similar performance to the C27J Spartan, but have the ability to also hover.
Hi DB, it’s nice to have you back for the technical articles.
The “afterburner” explanation makes a lot of sense, it’s no wonder the thing was so loud. I had previously tied myself in knots trying to work out how you were supposed to produce no torque from redirecting the air into the rotor blades with enough pressure to produce lift.
How good would these things be exactly?
Say you were a concept designer for Leonardo/Agusta/Airbus and planning a family of rotodyne type helicopters for the UK:
How much better would each of these be than the original helicopters?
I made ChatGPT write a long report on this potential “family of aircraft”, sorry if it’s a bit boring:
## Extended Report on the Rotodyne Family of Aircraft for the United Kingdom Armed Forces
### Executive Summary
This report presents a comprehensive analysis and design overview of a family of three advanced VTOL aircraft based on the principles of the Fairey Rotodyne. These aircraft, designated RT-1 (Rotodyne Assault), RT-2 (Rotodyne Medium Utility), and RT-3 (Rotodyne Heavy Transport), are intended to replace multiple existing helicopter and transport platforms within the British Armed Forces. This report details their design features, equipment, applications, and the feasibility of construction and maintenance.
### Introduction
The Fairey Rotodyne was a pioneering compound gyroplane that combined vertical takeoff and landing (VTOL) capabilities with the speed and range of a fixed-wing aircraft. This report explores the modern adaptation of the Rotodyne concept to create a family of aircraft suitable for various military roles, aiming to replace platforms such as the Apache, Wildcat, Puma, Merlin, Chinook, and Hercules.
### RT-1 Rotodyne Assault (RA-1)
#### Design and Equipment
**1. Airframe and Propulsion:**
– **Rotor System:** The RT-1 uses a large, advanced composite rotor for VTOL operations. The blades feature swept tips and noise-reducing designs to minimize acoustic signature. The rotor system is optimized for both lift during takeoff and efficient autorotation in forward flight.
– **Propulsion:** Rear-mounted pusher propellers powered by modern turbofan engines, such as the Rolls-Royce AE 1107C, provide forward thrust. These engines are chosen for their reliability and reduced noise output.
– **Fuselage:** Streamlined and reinforced with advanced composite materials to enhance survivability and reduce radar cross-section. The airframe incorporates stealth features such as radar-absorbing materials and infrared suppression systems.
**2. Armament:**
– **Chin-mounted Cannon:** A 30mm M230 Chain Gun mounted below the cockpit for direct fire support.
– **Wing-mounted Hardpoints:** Four hardpoints for various armaments including AGM-114 Hellfire missiles and Brimstone missiles for anti-tank roles, and CRV7 rockets for general-purpose use. Each hardpoint is positioned to ensure clear firing paths without interference from the rotor or propulsion systems.
**3. Avionics and Special Capabilities:**
– **Targeting Systems:** Equipped with advanced targeting systems, including Forward-Looking Infrared (FLIR), an AESA radar for targeting and situational awareness, and a laser designator for precision targeting.
– **Electronic Warfare:** Features an integrated Electronic Countermeasure (ECM) suite, Radar Warning Receiver (RWR), and infrared suppression systems to enhance survivability in contested environments.
– **Stealth Features:** The fuselage design incorporates reduced radar cross-section techniques and materials to lower the aircraft’s detectability.
#### Applications
The RA-1 is designed to perform assault and close air support missions. Its VTOL capability enables rapid deployment and extraction in combat zones, while its advanced armament and targeting systems allow it to engage a variety of ground targets effectively. The RA-1 can provide fire support for ground troops, engage enemy armored vehicles, and perform precision strikes in hostile environments.
### RT-2 Rotodyne Medium Utility (RM-2)
#### Design and Equipment
**1. Airframe and Propulsion:**
– **Rotor System:** The RM-2 uses a large rotor with advanced noise reduction technologies, including variable pitch and swept tip blades to minimize acoustic signature.
– **Propulsion:** Hybrid-electric propulsion combining traditional turboprop engines with electric motors for reduced noise and improved fuel efficiency. The primary engines are Rolls-Royce AE 2100, known for their reliability and performance.
– **Fuselage:** Spacious and modular, designed for easy reconfiguration to support various mission profiles, including troop transport, medevac, search and rescue (SAR), and anti-submarine warfare (ASW).
**2. Armament:**
– **Self-defense:** Side door-mounted 7.62mm M240 machine guns and optional 12.7mm M2 Browning heavy machine guns for defense during troop deployment and extraction.
– **ASW Equipment:** Integrated anti-submarine warfare suite, including deployable sonobuoys, a dipping sonar system, and torpedo launchers for Mk 46 or Mk 54 torpedoes.
**3. Avionics and Special Capabilities:**
– **Versatile Role Adaptation:** Capable of performing a wide range of missions, from troop transport to ASW operations.
– **Defensive Systems:** Equipped with advanced countermeasure systems, including flare and chaff dispensers, Directed Infrared Countermeasure (DIRCM) systems, and an integrated defensive avionics suite.
– **Advanced Avionics:** Features a multi-mode radar, FLIR, GPS/INS navigation systems, and advanced communication systems for coordination in multi-role operations.
#### Applications
The RM-2 is a highly versatile aircraft designed for a wide range of utility roles. It can perform troop transport, medical evacuation, search and rescue, and anti-submarine warfare missions. Its advanced noise reduction and defensive systems enhance its operational effectiveness and survivability. The RM-2 can operate from both land bases and naval platforms, providing crucial support across various operational theaters.
### RT-3 Rotodyne Heavy Transport (RT-3)
#### Design and Equipment
**1. Airframe and Propulsion:**
– **Rotor System:** The RT-3 utilizes a large rotor designed for heavy lift VTOL operations, featuring advanced noise-reducing technologies such as variable pitch and swept tips.
– **Propulsion:** Advanced turboprop engines, specifically the Rolls-Royce AE 2100, paired with hybrid-electric systems for reduced noise and improved efficiency.
– **Fuselage:** Enlarged with a rear ramp for vehicle and large cargo loading, constructed with reinforced composite materials for durability and weight reduction.
**2. Armament:**
– **Self-defense:** Side door-mounted 12.7mm M2 Browning heavy machine guns and rear ramp-mounted 7.62mm M240 machine guns to provide defensive firepower during cargo and troop operations.
– **Optional Hardpoints:** Wing-mounted hardpoints for Hellfire missiles and rocket pods to provide additional support capabilities if needed.
**3. Special Capabilities:**
– **Heavy Lift Capability:** Designed to transport heavy loads, including vehicles and large equipment, with a rear ramp facilitating easy loading and unloading.
– **Multi-role Versatility:** Capable of various missions, including troop and cargo transport, and potentially aerial refueling with modifications.
– **Defensive Systems:** Features advanced countermeasure systems, including flare and chaff dispensers, DIRCM, and reinforced structural components for enhanced survivability.
– **Advanced Avionics:** Equipped with multi-mode radar, FLIR, GPS/INS navigation systems, and robust communication systems for effective mission coordination.
#### Applications
The RT-3 is designed for heavy transport missions, capable of carrying large loads, including vehicles and heavy equipment. Its VTOL capability allows it to operate in environments with limited runway access, providing crucial logistical support in combat and disaster relief operations. The RT-3 enhances the UK military’s ability to conduct rapid deployment and sustainment operations, ensuring operational readiness in diverse environments.
### Feasibility of Construction and Maintenance
**1. Construction:**
– **Materials:** Use of advanced composites for strength, durability, and weight reduction. These materials provide enhanced performance characteristics and reduced maintenance requirements.
– **Manufacturing Techniques:** Employ modern automated manufacturing processes to ensure precision, improve production efficiency, and reduce costs. Techniques such as additive manufacturing and advanced assembly methods will be utilized.
– **Scalability:** Modular design approach to allow for scalability and customization based on mission requirements. This ensures flexibility in production and adaptation to evolving operational needs.
**2. Maintenance:**
– **Ease of Access:** Design considerations for easy access to key components to facilitate maintenance. This includes quick-release panels, modular components, and standardized fittings.
– **Standardization:** Use of standardized parts and systems across the RT-1, RT-2, and RT-3 to simplify logistics and maintenance. Commonality in components reduces the logistical footprint and enhances maintainability.
– **Training:** Comprehensive training programs for maintenance personnel to ensure high operational readiness. This includes initial training, ongoing professional development, and the use of advanced diagnostic tools and simulators.
### Conclusion
The proposed family of Rotodyne-inspired aircraft offers significant advancements in speed, range, versatility, and operational effectiveness. These aircraft are designed to meet the diverse needs of the British Armed Forces, providing a modern and highly capable VTOL platform. By incorporating advanced materials, noise reduction technologies, and modular design principles, these aircraft will enhance the UK military’s operational capabilities while ensuring feasibility in construction and maintenance.
The RT-1, RT-2, and RT-3 are poised to replace existing platforms and fulfill a wide range of military roles, offering improved performance, reduced noise, and enhanced versatility. With the adoption of these aircraft, the British Armed Forces will be better equipped to meet future challenges and maintain a strategic advantage, ensuring readiness and capability across various operational scenarios.
HI SB, had a look through your requirements below and I think a family of Rotordyne based convertiplanes is not only doable. But would also give the Forces a step change in capability. It would open up an export market, that will be looking for the next evolution past the current off the shelf aircraft, that can compete with the USA’s Defiant and Valor in particular equally, in terms of range and performance.
If we start with the Lynx/Wildcat replacement. Airbus are sort of ahead here, with their X3 prototype. Which is more of a compound helicopter than convertiplane. As the main rotor is still powered, but the drive to it is reduced by 25%. This slows the main rotor speed down enough so that the blade tips remain subsonic. This allows the aircraft to hit 255knots in level flight. Airbus have subsequently shown the RACER which uses the X3 concept. Though there has been no news of this concept being used for a military aircraft.
However, the X3/RACER is still limited by driving the main rotor shaft, which in turns spins the blades. So it will still
hit the transonic zone, where the tips go supersonic. Which equals lost lift and huge drag etc, and therefore limits speed to well under 300kts. By removing all drive to the main rotor blades and thereby turning the aircraft into an autogyro. The forward airspeed drives the blades to generate lift (though it will need a fixed wing to compensate for the lost lift), which
therefore stays in the subsonic zone for longer, so the aircraft will reach a much higher speed before hitting the wall. To be fair it won’t be as efficient as a fixed wing monoplane aircraft. As you have both a main wing and rotor disc generating drag. It should be similar performance wise in level flight to a
tilt-rotor, but better in the hover.
Fairey developed the Rotordyne from the Gyrodyne, which was originally a concept designed for the RN. This was a
relatively small aircraft, but shows the concept can scale down to a Gazelle size of aircraft.
For this replacement concept which fulfils the same roles as the Lynx/Wildcat. I would use an airframe with a pusher
propeller mounted in the tail, instead of engines/propellers mounted on the wing. The reason for this is to leave the main wings clear, thereby allowing weapons/stores to be hung underneath them. Which then doesn’t interfere with
the engine/propeller. It also helps ingress and egress of passengers. There is an option of using a biplane style of box wing, which will narrow wing span, but provide sufficient surface area. However, it may be better to use a mono
wing, that folds. As this is more efficient, but can also be folded down in the hover, to reduce the surface area. Thereby reducing the interference between the wing and main rotor. This can be further expanded by using both leading and trailing edge flaps, to further reduce the surface area.
As the thrust from the propeller is not required in the hover, it can be feathered. Whilst the 1st/2nd stage compressed
engine airflow can be partially redirected for use by directed reaction jets to control the aircraft’s yaw, as per the Harrier’s Pegasus engine. The engine will still need to run to power the generator and hydraulics. To power the tip jets compressed air. A second smaller engine is used to power a dedicated compressor. This is due to Fairey’s experience with the Rotordyne, that showed the tip jets robbed a lot of power from the engines. Though this does add a
parasitic weight, that isn’t required during forward flight.
The cabin layout will remain as pilot/co-pilot sitting side by side. With a passenger cabin for 6 to 8 pax, complete with two large sliding cabin doors.
In essence the aircraft will have a similar size and footprint to the current Wildcat, so it can fit on smallish warships.
But be significantly more efficient in forward flight, whilst still maintaining a comparable hover efficiency. Airbus have said their RACER will be at least 25% more efficient in performance than a comparable helicopter. This Rotordyne
version of a Wildcat will be nearer 45%. Its cruise speed could easily match the Valor at 250kts, but with a top speed around 300kts. Range will be a good question, as it should be better by 45%. Where the Wildcat’s published internally fuelled range is around 750km, this concept should be over 1000km.
Material wise, there’s a lot to be said by using composites, as they reduce weight. Therefore, increasing the aircraft’s performance (less mass to move). However, this comes at the expense of maintainability and readiness. Which as a battlefield support role, it will be expected to take incoming small arms fire (it’s inevitable)! Therefore, I would choose a metal airframe and skin. As these are far easier to maintain and repair.
The heavy lift replacement. For this I am going to target the CH47 Chinook and CH53K King Stallion, as there is nothing
else comparable in the Western world. I would base the cabin size around the dimensions of the CH53K rather than the CH47, as it wider, though has the same height. Like the CH47 and CH53 it would have a ramp, but like the NH90 a pair of cabin sliding doors. this will speed up ingress and egress.
Layout wise it would be similar to the Rotordyne. With a fairly high mounted main wing that provides 50% of the lift
at cruise speed. The wing tips would be capable of folding down to reduce the parked footprint. But when integrated with the wing’s forward and training edge flaps. Reduces the wing’s surface area to minimize the interference between the
main rotor and wing when in the hover. There would be 7 rotor blades constructed from metal mix composites. By using 7 blades you can reduce the blade length, but balance it out by increasing the overall surface area. Thereby increasing the maximum lift (all up weight) in the hover. I am aiming to match the CH53K’s 16t payload. It will also make the aircraft quieter in forward flight.
For commonality, I would have picked a derivative of the T56 engine used by the Herc. But as that is no longer in service with the UK, a derated version of the A400M’s Europrop TP400 will suffice. Where 11,000shp is overkill and around 7000 to 8000shp would be sufficient. I am in two minds to have the propeller mounted as a pusher or in a tractor layout (puller). The tractor layout is slightly more efficient, as the
propeller gets an undisturbed airflow. However, if there is a sliding door near the front of the cabin. The propeller is likely to be nearly in line with it. So ingress and egress could be an issue. If the propeller is behind the wing this helps with ingress/egress, but is slightly less efficient as its gets a
disturbed airflow from the wing.
The QE class hangar has a maximum height of 10m. Which means the legacy Rotodyne design with a height of 22ft 2in (6.76m) would easily fit in the hangar. Length wise, it could stay the same at 58ft 8in (17.88m). But have a cabin size comparable to the CH53K at 9ft (2.74m) wide. Which is around 34cm wider than the legacy Rotordyne’s.
In summary we could have a modern Rotordyne aircraft, that is comparable to the CH53K in payload lift capacity. But with
the convertiplane advantage in forward flight.
For the Puma/Merlin replacement it gets a little bit tricky as these two aircraft are in different weight classes. You could scale up the Wildcat replacement, so it carried 10 to 12 pax or go bigger for the Merlin replacement with 24 pax. I would still prefer a mix of cabin sliding doors and a tail ramp. However, the larger heavy lift concept, is really too big for a frigate. But for the Merlin replacement, we could use a
scaled down heavy lift version of our modern Rotordyne, i.e a twin on-wing turboprop. One of the key requirements, is that it would have to fit an frigate’s hangar. Which might be bit of an ask, as its likely to be quite a bit taller. It will be required to do all the current Merlin tasks, along with carrier onboard delivery (COD). Plus, it gives a twin engine redundancy in case of emergencies. But it should be more than capable for maritime strike, ASW and commando assaults. As it will have a much better range, speed and time on station compared to a Merlin.
But could it replace Crowsnest? The cabin would have to be pressurized, so the crew can safely operate above 10,000ft for long periods whilst on station. As you really want the aircraft to fly as high as possible, hopefully over 20,000ft. Finding a location to mount a large, long-distance S-band radar may be a bit of a problem. As you have a large rotating disc on top of the aircraft and two smaller ones on the wings. However, if the radar was mounted conformally along the fuselage. Possibly split into fore and aft sections either side of the wing joint. This should give a clear an unobstructed view. As the aircraft can take the weight and will have plenty of electrical power. It should be able to have one mounted on either side of the fuselage. I would include a look down horizon scanning X-band radar. Specifically, to search for sea skimmers and other really small radar targets. Due to its
size, it would still be manned. Though it would still relay info back to a task group via broadband data-link
The other role it could do is as an aerial tanker. It will be fast enough for the F35 to refuel from it at an economical speed. Depending on the wake behind the aircraft and length of the drogue hoses. It might also be able to refuel two aircraft at once. Being able to carry at least 12t of additional role fitted bagged fuel, will be a huge bonus.
The interesting version would be the Apache replacement. A tandem cockpit arrangement would be favourable to give a narrow fuselage. Utilising a single pusher propeller and yaw controls similar to the Wildcat replacement. You could include internal weapons bays along with underwing stores. But should it be stealthy? It should definitely meet the visual, infrared and noise low observability requirements, but what about radar? You can give the aircraft a diamond profile shape similar to that used for the Commanche prototype. Which along with some painted-on RAM to reduce its
radar signature, should give it a pretty sporting radar cross section (RCS). But I feel composite based embedded RAM (eRAM) as used on the F35, would make the aircraft too fragile and easily grounded. Due to the amount of time that is
required to make repairs. Whereas a painted-on RAM on top of a metal skin. Will make it much easier and faster to repair, thereby increasing its readiness. Bearing in mind this aircraft is expected to be at the front line and will be targeted by small arms fire amongst other threats. The internal weapons bays are inherently radar stealthy, so if you forgo any stores/pylons under the wing, it will still be significantly stealthier than an Apache.
You could in essence be replacing not only the Apache type of attack helicopter. But to an extent the role of the A10 in
close air support.
I have been thinking about this for quite some time. The Rotordyne convertiplane was ahead of its time. But with modern materials and digital modelling. I believe, we could design and build an exceptional aircraft that could branch into a family of aircraft. That would be highly competitive on the World market. But also produce a significant step change in capability on par with the Defiant and Valor.
I feel cheap now; I just ask questions and feed prompts into an AI writer, and you seem to have spent this afternoon writing a whole essay purely for my benefit. Thanks and very, very much appreciated 👍
Wouldn’t the largest design be most suitable for AEW? It would have plenty of space and weight for extra fuel tanks along with heavy radar. Unlike a Merlin replacement, the only space requirement is to fit down the lifts on an aircraft carrier, each of which takes 2 F35 with room to spare.
Also, would it be viable , wrt the light Wildcat type, to use a rear propeller that is capable, with clever pitch control, of producing a yaw effect? I’m imagining something like a radial Voith-schneider propulsor that angles the blades to produce thrust in a given direction. Failing that, hovercraft-style thrust vanes would also produce a yaw effect.
If you ever do set up Convertiplane LTD and need someone to help around the office etc, you know who to ask!
Absolutely and every time – sacrilege that they scrapped the only working model I never get why we have that policy in the UK, see nimrod too circa 2010 etc.
Could it be fitted with a radar on top for use as a STOVL AEW&C aircraft for carrier use?
I dunno, even if it could lift that, getting the equipment in the cabin would be intresting. If that was the case Italy would be lookin at it I’d hope. Their Merlin AEW pretty much failed.
Only roles I’ve seen mentioned for it so far are rapid troop transport and medevac
FYI the Fairy Rotodyne had a party trick it could lift a 100 ton Girder Bridge and hover with it,
Hi ABCRodney,
I think you’ll find it was a 100 ft girder bridge rather than a 100 ton girder bridge. Still a very impressive achievement as it would have been an unwieldy load and I can think of no other vertical take off rotor craft being able to do that in the late 50’s early 60’s.
Cheers CR
The problem (other than its woefully, troubled prolonged gestation) is that unless the agreement with Bell has changed this aircraft cannot be armed. Now how far the definition of ‘armed’ goes into defence procurement may not be publicly clear here, but if you use it on a naval ship with all the related costs of so doing being unable to arm it hardly makes it attractive whatever its main duties might be. Bell didn’t seem to think its potential was such that it wanted to pursue it (military or commercially) so I remain unconvinced that an aircraft first planned for sales some 15+ years ago even with big modernising re designs in the meantime is something I would wish to invest in.
Last year the relationship between the two firms (now Bell and Leonardo) was renewed.
My apologies: it was earlier this year. Hasn’t time flown!
http://www.leonardo.com/en/press-release-detail/-/detail/29.02.24-bell-ldo
Not at present..as it’s civilian only and this was once the Bell Augusta 609…it’s pretty well know bell did not hand over the military use licence when it sold its share in 2011…as its been wanting to develop its own medium lift military tilt rotor ( the V280).
looks like AW think they have scope to develop it as a paramilitary machine…..
Why doesn’t the USN try a De Havilland DCH Buffalo landing on a carrier
It could probably land with a greater weight or number of troops than any tilt rotor.
If the USN wants a truly better aircraft they should ask Viking Air to design a new craft based on their jet with blown flaps design that De Havilland did in the past.
Unless that entire wing section rotates like the V-22 it would take up more space than a pair of Merlins and way more than a V-22. That makes it pretty useless for any platform where space is at a premium.
Keep trying though because we need something for COD work in the RN
Precisely. I think this is just a trial for land-ship-land supply function.
It seems to have taken a staggering amount of time to get to this point. The initial concept in the late 1990’s. The landing trials on the Aircraft carrier, are to do with the oil and gas sector.
Although this is a brilliant if costly replacement for medium life rotors ( same load, more passengers, pressurised cabin, twice the ceiling at 25,000 feet, almost twice the range at 900miles fully loaded, and 30% faster at over 300mph) ..it has one big problem..before it was the AW609 it was bell Augusta 609..and when AW purchase Bells stake it was pretty well know that Bell refused to all it to be developed as a military tilt as they wanted to develop their own ( V280)…which means it’s very likely unless the U.S. does not do its usual screw over protectionism the AW609 will never be developed with military applications…which is a shame really.
I bet Bell and Leonardo could come to a licensed agreement. Leonardo license builds many other manufacturers aircraft and is not afraid to work with others in the industry. For example, Leonardo builds the international market CH-47s. I’m sure Bell won’t let them do it for free, but there is no reason why Bell wouldn’t want to cash in on some license rights and make a bit of money on the 609 which they spent a lot of development on. There are a lot of European governments that would much rather purchase from a European manufacturer.
Also Leonardo’s next gen tilt rotor is learning a lot from the V280, it is gaining the V tail configuration and is concepted o have the fixed engine with a rotating gearbox.
From what I have read I think Leonardo are hoping for that..but I would imaging they will pay out the nose for it if they can get it..but I’m not sure Bell will play ball as why would they enable a direct competitor to V280 in a profoundly limited market.
I’m not so sure they really would compete with each other. The AW609 is much smaller than the V280 and has a pressurized cabin so it’s service ceiling is 25,000 ft vs 6,000.
I have to say that the AW609 if competitively priced would be a solution for the RN on the carriers. The question is this
1) It provides a significant increase in altitude and range for AEW work which is one of the problems with Merlin, with inflight refuelling (which Merlin can not do) the range should be significant. The question is can it be purchased cheaper than the from ground up new Drone capability that RN seems obsessed with and could it be operational before the Merlin AEW option is pulled from service. Quite simply is integrating a known AEW Radar System on to a mature platform that the AW609 is cheaper and quicker than building a Drone and the limitation on data transmission etc.
2) The other question is regarding ASW Work. Again we know that helicopters of any sort have a range limitation. With the advances in torpedoes/missiles and drone submarines I think both us and the USN need to extend the ASW sanitised bubble around Carriers/Amphib ships. The question is could you take the established kit from Merlins, buy new sets and install them on AW609. After the USN retired it’s S3’s they have a glaring gap and maybe Yeovil could in the future be supplying the USN with a solution whilst the RN are buying MQ25 refuelling drones. Not only could these aircraft free up enough Merlins for close in protection and to operate in enough numbers from Frigates etc where we are struggling for numbers, they could also assist/supplement P8’s in for example clearing the Clyde approaches when nuclear subs deploy etc thus freeing up the P8’s which are stretched in numbers.
As in all these things it comes down to money and political point scoring in the RN. Is it cheaper than a brand new Drone design and with the RN look at it and not get hooked on justifying Cat and Traps on PoE and QE based on the existence of that drone. A drone that by taking data processing of platform to ship will be relying on new tech for flying and transmitting the data all which increase the risk to the programme.
wonder how many they can put in the hangar given the huge wing and the fact there is a massive engine sitting at each wing tip.
Doesn’t look too sturdy either.
Biggest issue to service is Aw/leonardo’s buyout of the program from Bell stipulates that no armaments may be fitted to a 609, offensive or defensive. So cargo and out of theatre transport only