Night intruder - the Osprey is at home in the dark (USAF).

As the USAF’s CV-22 Osprey detachment in the UK continues to ramp up to full strength, TIM ROBINSON reports from the 16th Raoul Hafner Memorial Lecture at the UK's Defence Helicopter Flying School based at RAF Shawbury which saw presentations on the entry of AFSOC’s tiltrotor into service.

The Bell/Boeing V-22 Osprey has had a difficult and highly public gestation. Though the dream of a fixed-wing aircraft that can also hover and land like a helicopter is almost as old as aviation itself, the dreams of engineers have produced few operational, production examples. Today, the Osprey is, after the Harrier, the most successful of these VTOL designs and now, with over 250 delivered and combat service in Afghanistan, Iraq and Libya, along with humanitarian missions recently in the Philippines, the V-22 has proven its worth. It still is new, evolving technology, but no one now disputes that it provides US forces (and will provide foreign customers) with a unique air mobility capability.

On 1 May at the Defence Helicopter Flying School VIPs and students were privileged to hear from the USAF’s UK-based Osprey unit — the 7th Special Operations Squadron at RAF Mildenhall in the 16th Raoul Hafner Memorial Lecture. Giving the operators’ perspective, was Captain Tyler Oldham (an Osprey pilot and instructor now on his second tour) from RAF Mildenhall. He was unusual in that he was one of the first CV-22 pilots to go straight into tiltrotors direct from training — rather than, has been the case until now, from either the fixed-wing or rotary-wing community.   

The CV-22

The CV-22s avionics suite allows for pinpoint navigation anywhere on the globe.

So what are the differences between the MV-22 (US Marines Corps) and the CV-22 (USAF) Ospreys? Captain Oldham made an analogy using cars — with the MV-22 being the base model, and the CV-22 coming with the optional extras — such as leather seats, electric sunroof and the like. The main external differences are bigger fuel tanks, and the terrain-following and avoidance radar (TFR). The TFR allows flight down to 100ft. The CV-22 also features four crew (two pilots and two flight engineers — one of whom sits up front with the pilots on a jumpseat). This, given the CV-22s highly  complex missions, is one more crew member than the MV-22 Marine version. The CV-22 also features a digital colour moving map and sophisticated navigation avionics including three INS systems and a GPS. This allows the crew to navigate to any point on the globe in perfect darkness. The aircrafts navigation avionics can store 999 waypoints and can allow missions to be replanned in flight to take account of changing situations.

The CV-22 also features an extensive EW and defensive aids suite — which Capt Oldham was careful not to elaborate about in this professional, yet open forum. For communications AFSOC’s Osprey also features UHF/VHF/FM radios as well as SATCOM. These digital radios not only allow the special operations troops to communicate with external assets, but can also relay ISR imagery, including full motion video to SF commanders on board. The CV-22 features 24 seats in the back, but in practice this would be 18 fully equipped SOF troopers. The aircraft also comes with a hoist and a fast-roping system to allow troops to insert without the Osprey landing.

 The CV-22 Osprey’s range (500nm) is also enhanced by the dedicated MC-130J Commando II special operations aircraft able to refuel it in flight — giving it a full range of 2,100nm or four-to-five hours in the air.          

The 7th SOS at RAF Mildenhall

The first two AFSOC CV-22s for RAF Mildenhall arrived in 2013. (USAF)

The 7th SOS, part of 352nd Special Operations Group,  Air Force Special Operations Command (AFSOC), provides long-range, all weather, day or night, clandestine personnel insertion or extraction. With RAF Mildenhall-based MH-53 Pave Lows deactivated in 2007, the arrival of the first CV-22 Ospreys in June of 2013 resurrects a key long-range vertical insertion /resupply role. As noted above, AFSOCs CV-22s at RAF Mildenhall provide a rapid deployable capability for covert special operations forces — at twice the enroute airspeed of the helicopter it replaces. As well as the fast-roping and hoist, the CV-22 can deploy SF forces via military free-fall from the back ramp. The CV-22 is able to conduct shipboard deck landings and fully blacked-out operations at night in all weathers, as well as NVGs at low-level. 

 The unit has five CV-22s at Mildenhall and at full strength will field ten Ospreys in the next year or so. As of May, the 7th SOS has seven crews for those aircraft. So far the according to 7th SOS Operations Officer, Lt Col James Peterson, the experienced crews are evenly split between fixed-wing and rotary backgrounds, but he says now two-thirds of new pilots joining the squadron are now direct entrants straight from training — and can come from either rotary or fixed wing pipelines.     

For CV-22 pilot currency, the goal is 15hrs a month in the actual aircraft and 10hrs per month in the simulator — one of which is installed at Mildenhall.

Meanwhile, Lt Col Peterson, speaking to AEROSPACE explained that initially as a new type, the CV-22 had been restricted in the use of UK airspace by the UK MoD — with early training flights taking place in Norfolk around the home base. This has now been lifted and Ospreys are venturing further afield, with recent visits to the ‘Mach Loop’ in Wales. The 7th SOS are also now looking for unprepared (but surveyed) landing sites around the UK to hone their skills.

Lt Col Peterson explained the Ospreys appeal to AFSOC: “The thing that’s important is you now have expanded time, because you can get somewhere, twice as fast and you now have more time to do whatever you need to do at that location”. Given that many missions of the CV-22 take place at night, this capability to squeeze extra mission time before daylight breaks is key.

AFSOC will eventually field 50 CV-22s in total — with its full operational capability scheduled in 2017.

From the pilot’s perspective

The Ospreys high-speed brings new capabilties to AFSOC. (USAF)

During the lecture, Capt Oldham explained some of the nuances and capabilities of the tiltrotor. For example, if flying down a narrowing valley or tightly constricted terrain, then the pilot could tilt the nacelles to 60degrees and slow down to 110kts, enabling the CV-22 to hug the ground lower or reduce its turning circle dramatically. Approaching a potential threat area — a CV-22 pilot also has the option, unlike helicopters, of climbing higher to 25,000ft and overflying the threat at high speed — although he admitted that they rarely flew that high.

The Ospreys high speed is one of its chief advantages. Its cruise speed in 230kts, with a dash speed of 280kts. Capt Oldham explained that the 7th SOS is already training with other US and UK air assets, including AAC Apaches from nearby Wattisham. Requests from Apaches to ‘escort’ the CV-22s airborne on local training flights does take place — but Oldham noted that the Apaches have difficulty keeping up with the Ospreys until the CV-22s slow down to land.

The high speed of the V-22 also brings benefits in the medvac/casevac role. While the Osprey can carry 12 stretcher litters there is (yet) no dedicated medvac version. However experience with the Marines in operational theatres has found that a lack of paramedics onboard has been more than offset by the higher speed of the V-22 in whisking the injured to hospital far faster than rotary wing platforms in the ‘Golden Hour’.

Captain Oldham explained for very heavy weights a running takeoff similar to a fixed-wing aircraft is used from the runway, but this more of the exception. Saving fuel here, when the aircraft is at max weight, thus pays dividends later on when it may need that extra fuel to manoeuvre or conduct VTOL landings. At lower weights helicopter-style takeoffs are very common, with the nacelles at 80degrees to provide a 'jump' into the air.

Much interest at the lecture was on the Osprey’s landing and autorotation performance. Capt Oldham admitted that it was heavy (50,000lb max take-off) aircraft and thus the CV-22’s deceleration to landing was not like a helicopter: “you need a power margin to stop a 50,000lb aircraft”. Though it is a heavy aircraft, its limited autorational ability has more to do with the low inertia rotor system and beta governing of the blades than the aircraft weight.

Pedal spot turns in the hover though, are quite spritely, with the same (30 deg per second) turn rate as a normal helicopter. Lt Col Peterson, an ex-Pave Low pilot, meanwhile had high praise for the Osprey’s fly-by-wire system after ten years flying it: “It's about the most stable aircraft I’ve flown”. He added: “Having flown numerous other helicopters I feel more comfortable in this machine, maybe more so, than anything else I’ve ever flown.”        

Ospreys around the world

Rear cabin of the CV-22

Some 259 Ospreys have now been fielded — the majority with the USMC and as AFSOC continues to move towards full operational capability with its Ospreys, the V-22 is on the verge of finding new operators and potentially new roles and missions. Also speaking at the Raoul Hafner Lecture was Robert Torgerson, Senior Manager, Rotorcraft Business Development, Boeing, who outlined the development history of the V-22, its current operators and expanding potential. On the latter, the type has recently won its first export orders with Israel and is set too to be potentially purchased by Japan.

Meanwhile new roles are also being proposed for the V-22. Only earlier this year at the Singapore Air Show it was revealed that AFSOC and Bell/Boeing are studying a potential gunship version of the CV-22 — to give the air commandos added punch. Meanwhile air-to-air refuelling trials have already taken place using an Osprey as a tanker and a F/A-18. There were, said Torgerson, “lots of modular applications” including SAR, MEDVAC, and VIP roles.

Probably the ‘most significant’ opportunity, explained Torgerson, was the hotly contested US Navy’s Carrier On-board Delivery (COD) requirement. Responding to a question from the floor, Torgerson quipped that a V-22 COD version would also be useful for “any country” with “two large aircraft carriers” — a pointed reference to the UK’s Queen Elizabeth ships.  Whether the V-22 one day might ever wear a UK military roundel is unknown – but from the audience there certainly seemed to be no shortage of volunteers to fly the Osprey — even as exchange pilots.

Finally the comments from AFSOC and Boeing at the lecture indicated that while, as the first operational tiltrotor in the world, the V-22 was ‘still a learning process’ — the cost per flying hour and reliability of the platform have been improving — especially in the past few years. Lt Col Peterson says of the CV-22:  “Like any rotary-wing aircraft, generally they are maintenance intensive machines — but our readiness rates and aircraft availability are in line with mature helicopters”. This was echoed by Boeing’s Torgenson: “A lot of reliability issues are a thing of the past”. Indeed, it was noted that as the first of a new type of flying machine, the true comparison for reliability arguably might be the Sikorsky R-4 — the first large scale production helicopter.

Furthermore, while the V-22 is currently a niche capability for America’s special operations and first-to-deploy amphibious forces — the tiltrotor, it seems, is here to stay. AgustaWestlands AW609 is aiming firmly at the civil market, while a concept from Bell and Lockheed Martin for the US Joint Multirole Rotorcraft (JMR) sees a smaller, tiltrotor, the V-280 Valor — that, if selected, would see the tiltrotor become as ubiquitous as the UH-60 Black Hawk.           


Long range combat rescue and insertion are the CV-22s main missions.(USAF)

In conclusion then, this lecture provided a fascinating insight into the use and missions of this niche tiltrotor. At a time when NATO is quickly bolstering its forces in Europe due to uncertainty and tensions with Russia, this reconstitution of AFSOC’s long-range VTOL CSAR and insertion capability at RAF Mildenhall could not be more timely — and provides US decision-makers and the Pentagon with a unique air power tool. 



The 16th Raoul Hafner Memorial Lecture


Bristol had studied a tiltwing concept the late 1950s. 

The annual Raoul Hafner Lecture, held by the Defence Helicopter Flying School (DHFS) and strongly supported by Royal Aeronautical Society, seeks to link the science, engineering and art of rotary-wing flight with the students attending one of the world's foremost helicopter training schools. Giving the introduction at the lecture was retired flight test engineer and aviation historian David Gibbings FRAeS MBE, who observed that aviation pioneer Raoul Hafner, the designer of the Bristol Sycamore and Belvedere had proposed a very unusual passenger tiltrotor design in the 1950s. This unusual concept would have taken-off and landed vertically as a tailsitter — attaching itself to the side of riverside wharf buildings like the 1950s Ryan X-13 Vertijet. The seats would have rotated around an axis for horizontal flight. It would have been, observed Gibbings, a ‘sporty take-off’ for passengers.   

The 2014 lecture on 1 May was followed by a highly informative and penetrating question and answer session from the floor, on the Osprey’s flying characteristics, its handling and manoeuvrability. Finally the event finished up with a drinks reception sponsored by Boeing.  

VIPs at the lecture (from l to r): Ben Clothier — Raoul Hafner’s Grandson, David Gibbings – Yeovil RAeS, Colonel Mike O’Donoghue (Ret’d) — RAeS Rotorcraft Group, Bob Torgerson — Boeing, Captain Paul Shawcross Royal Navy — Commandant DHFS, Captain Tyler Oldham USAF — 7th SOS, RAF Mildenhall, Jenny Body — then RAeS President, Lt Col James Peterson USAF — 7th SOS, RAF Mildenhall, Robert Dompka – Bell Helicopter Textron, Colonel Neale Moss (Ret’d) — Boeing Defence UK.



5 June 2014