Selling the Osprey.
The technological challenge of filling the gap between the basic helicopter and a conventional fixed-wing aircraft has led to many different approaches, of which currently the best established is the tilt-rotor.
Every helicopter tilts its rotor to generate a forward thrust component and thus accelerate from the hover into forward flight. However, in a conventional helicopter the angle through which the rotor can tilt relative to the airframe is mechanically restricted.
What is different in what has become known as the 'tilt-rotor' is that the rotor can be inclined through approximately 90 degrees relative to the airframe and thus generate far higher propulsive thrust. A tiltrotor is much faster than a basic helicopter, but not as fast as a turboprop, because its rotor tips (turning at large radius) run into compressibility effects at lower airframe Mach Numbers.
The basic tilt-rotor idea is old. In the early 1920s Henry Berliner, in the United States demonstrated a biplane helicopter with two rotors that could tilt through a substantial angle. A 1930 US patent by George Lehberger illustrated a single-engine helicopter with coaxial, contra-rotating rotors and a drive shaft that was articulated just above the fuselage. However, the front fuselage restricted tilt-angle, and the concept failed to address the basic necessity to keep the rotor thrust acting through the centre of gravity, regardless of tilt angle.
What arguably set the precedent for current American developments was a British patent for the 'Baynes Heliplane' in the late 1930s, which had wingtip-mounted tilting power plants and rotors.
In practical terms, the father of tilt-rotor aircraft appears to have been the 950-kilogram Focke-Achgelis Fa 61 of 1936, which had non-tilting rotors mounted on tubular trusses on either side of the fuselage. It is mainly remembered for 1938 demonstrations by test pilot Hanna Reitsch inside the Deutschlandhalle stadium in Berlin. The Fa 61 led to the 4,315-kilogram Fa 223 assault transport of 1940, the first helicopter to have neared mass production status (Allied bombings ensured this did not happen).
The company's success with a fuselage-mounted engine driving 'outrigger' rotors led to the Focke-Achgelis Fa 269, a tilt-rotor vtol fighter project, designed to operate from dispersed sites. Strangely, it was given pusher propellers, which for take-off and landing were turned downward. Great as a lawnmower, not so good for an aircraft! This arrangement also necessitated a very long undercarriage that telescoped to allow retraction.
A 1941 RLM (Reichluftministerium = State Air Ministry) design study contract led to tunnel tests and the construction of a Fa 269 mock-up, but this was destroyed by Allied bombing in 1944. The project was then abandoned, as it appeared unlikely to fly before 1947.
The Fw 61 also inspired some rotorcraft developments in the United States, notably the Platt-LePage Aircraft XR-1A, which won a US Army Air Corps competition in 1940 and flew in 1941. Although of limited success, the XR-1A led the company to plan a 24,000 kilogram tilt-rotor project, for which a patent was granted in 1955.
One of the engineers who worked for Platt-LePage went on to found Transcendental Aircraft, whose 800-kilogram Model 1-G tiltrotor aircraft began hover trials in 1954 under partial US Army/Air Force funding. It explored much of the conversion envelope, but never completed a full transition to wing-borne flight.
The first tilt-rotor project to achieve full transitions between rotor- and wing-borne flight was the 2,220-kilogram Bell XV-3, which (like the Fa 269) had a single fuselage-mounted radial engine, but the more practical arrangement of tractor rotors that tilted upward for low speed operation. The first of two prototypes began hover tests in 1955. Between 1959 and 1962 the XV-3 completed 110 transitions.
The XV-3 was one of three designs developed and tested under the US Army/Air Force Convertiplane Program, which aimed to achieve major improvements over simple helicopters in hover duration, cruise speed and range. However, the Convertiplane was (optimistically) supposed to retain the low disc loading of a helicopter, in order to produce at the hover the moderate downwash desirable for rescue operations.
Although it experienced serious problems during flight trials, the XV-3 paved the way for the twin-turboprop 6,000-kilogram Bell Model 301 or XV-15. This was the real precursor of today's V-22 Osprey, having wingtip-mounted tilting power plants (it may be noted that the competing Boeing-Vertol Model 222 tilt-rotor had fixed wingtip-mounted engines). The first of two XV-15 prototypes began flight trials in 1977 under Nasa funding. The second aircraft continued flying until 2003 in support of the Osprey programme.
What brought urgency to the development of a high-speed rotary-wing aircraft was the catastrophic failure of America's Eagle Claw Operation of 1980, aimed at liberating the 52 hostages held by Iranian militants in the United States embassy in Tehran.
In 1981 the Pentagon launched the JVX (Joint Vtol Experimental) programme, initially under US Army leadership, although two years later the lead was to switch to the US Navy and Marine Corps. Undoubtedly influenced by the successful flight trials of the Bell XV-15, in 1983 a preliminary design contract was awarded to the Bell Boeing team, and in 1986 full-scale development of the V-22 project was launched. At that stage all four US services had requirements for the JVX, but in 1988 the US Army left the programme.
The first of six Bell Boeing V-22 Osprey FSD (full-scale development) aircraft (c/n 90001-6, BuAer 163911-6) began hover trials in March 1989. This batch was followed by four EMD (engineering manufacturing development) aircraft (c/n 90007-10, BuAer 164939-42).
Nine years of low-rate initial production in FY97-05 followed. The first four runs (Lrip-I to -IV) totalled 29 MV-22 Block A aircraft (c/n 90011 to 90039), which were used by the Marine Corps only for training. The third aircraft from Lrip-III (c/n 90025, BuAer 165839), which had been delivered to the Marine Corps in 2001, was later converted to become the first CV-22B (serial 99-0021), which included substituting different radios and adding a terrain-following radar.
In September 2005 FRP (full-rate production) was approved. Two years of FRP in FY06 and 07 (Lots 10 and 11) were followed by the first Multi-Year Program (MYP), covering 174 aircraft in FY08-12 (Lots 12-16). This has led to MYP-II, covering 99 aircraft in FY13-17 (Lots 1721). The Program of Record calls for 360 MV-22Bs for the US Marine Corps, 50 CV-22Bs for the US Air Force, and 48 MV-22Bs for the US Navy, although the Navy buy is currently unfunded.
The MV-22B achieved initial operational capability in June 2007 with Marine Medium Tiltrotor Squadron VMM-263 'Thunder Chickens' replacing the Boeing Vertol CH-46E. In late 2007 the unit deployed from its base at MCAS New River, North Carolina, to Iraq with ten Ospreys aboard the LHD-1, USS Wasp.
The CV-22B entered service with Afsoc's 8th SOS (Special Operations Squadron) 'Blackbirds' at Hurlburt Field, Florida in 2006, and attained initial operational capability in March 2009. The 8th was deployed to Iraq in 2009 and to Afghanistan in 2010. The CV-22B augments the Lockheed Martin MC-130 series, infiltrating, exfiltrating and resupplying special forces.
The V-22 has a maximum vertical take-off weight of 23,859 kilograms, although in operational short take-off it can gross 25,855 kilograms, while maximum ferry take-off weight is 27,443 kilograms. It has a rotor diameter of 11.6 metres, giving a vto disc loading of 113 kilograms/square metre (compared to 73.6 for a Sikorsky MH-53E). Maximum cruise speed is 493 km/hr, making it almost twice as fast as a helicopter. It has a service ceiling of 24,000 feet, but is not pressurised, hence when transporting personnel it cruises at 8,000-13,000 feet.
Under sea level standard conditions it can deliver 24 troops to a radius of 780 kilometres, or 1,280 kilometres with one aerial refuelling. It can carry 9,000 kilograms of cargo internally, or a combined total of 5,670 kilograms as two sling loads. It is equipped for in-flight refuelling and is designed to ferry 3,400 kilometres with one aerial refuelling. It is the only rotary-wing aircraft capable of self-deploying quickly anywhere in the world. Its rotors fold and its wings rotate to facilitate stowage in an aircraft carrier or hangar.
Boeing is responsible for the fuselage, all subsystems, the digital avionics and fly-by-wire controls. Bell is responsible for the wing, tail surfaces, transmissions, rotor systems and engine installation. Bell also carries out fmal assembly at its facility at Amarillo, Texas.
Rolls-Royce provides the 4,586-kW AE1107C turboshaft engines. Standard fuel capacity is 6,513 litres in the case of the MV-22B, and 7,667 litres for the CV-22B.
The V-22 is currently in service with 14 US Marine Corps and four Air Force squadrons. It suffered some accidents initially, but after various modifications and improved pilot training in the last ten years it has had one of the lowest Class-A mishap rates of any tactical rotorcraft in Marine Corps service.
The V-22 was designed to satisfy the amphibious/vertical assault needs of the US Marine Corps, the long-range special operations needs of the US Air Force, and the strike rescue, special warfare and fleet logistic support needs of the US Navy.
However, there have been concerns over the suitability of the V-22 for the rescue mission (due to its strong downwash at the hover), and the Navy appears to be assessing it primarily as a replacement for the 24,600-kilogram Northrop Grumman C-2A Greyhound COD (carrier onboard delivery) aircraft, of which the service has around 35.
Although criticised for its unpressurised cabin, which would mean flying through (rather than over) bad weather, the V-22 would provide far greater operational flexibility than the C-2A. It would be able to supplement US Marine Corps MV-22Bs in the assault role and Navy's Sikorsky MH-60S in the combat search-and-rescue role. In its basic mission, the US Navy Osprey would be able to deliver cargo to smaller ships, and would provide longer range and faster resupply than current VOD (vertical onboard delivery) helicopters. It could also operate by day and night, which the C-2A cannot.
The versatility of the V-22 may be further enhanced by the development of a roll-on/roll-off aerial refuelling kit, which interests the US Marine Corps as providing a tanker for the Lockheed Martin F-35B. A preliminary series of flight tests funded by the Bell/Boeing team was carried out in August 2013, using a high-speed hose-and-drogue system on an MV-22B of Marine Tiltrotor Test and Evaluation Squadron VMX-22 'Argonauts', based at MCAS New River, North Carolina.
The MV-22B would probably be the better choice for a C-2A replacement in the long term. However, in the present cost-cutting environment the Navy may be forced simply to have its C-2As refurbished and upgraded, and delay their replacement.
Considering that the MV-22B has been in service for seven years, international sales have clearly been difficult to achieve. Aside from a series of accidents in the 1990s (four hull losses and 30 fatalities), foreign interest has been deterred by the relatively high cost of the aircraft.
In March 2014 a single CV-22B was ordered for the US Air Force at a cost of $ 76.1 million. The FY15 budget request asks for 19 MV-22Bs at a unit cost (without spares) of $ 80.7 million, almost as much as a $ 88.9 million Lockheed Martin C-1 30J Hercules.
Doubts over the suitability of the V-22 for the Csar (combat search-and rescue) role were partly allayed by the March 2011 rescue of a US Air Force F-1 5E pilot from Libya by an MV-22B from LHD-3, USS Kearsarge, operating at a radius of 245 kilometres.
In striking at Gaddafi's forces from ships off the coast and tanker orbits over the Mediterranean, coverage was limited by the reach of Csar assets, beyond which cruise missiles were used. The availability of MV-22Bs was therefore crucial to the success of Coalition air operations. In addition, downed aircrew knew that help was coming twice as fast as with traditional helicopters. In the case of casualties, it is vitally important to commence treatment in the 'golden hour' after injury, and the V-22 makes this far more feasible.
The MV-22B is exposed to enemy fire for a shorter time period than a helicopter, and can fly above small arms fire. Its faster cruise also means that it can be escorted by fixed-wing combat aircraft, such as the Boeing F/A-18, rather than an attack helicopter.
The MV-22B has proved its usefulness in several humanitarian relief operations. For example, in January 2010 MV-22Bs from the 24th Marine Expeditionary Wing took part in Operation Unified Response, after a major earthquake struck Haiti. Likewise, after Typhoon Meginuan hit the Philippines in October 2010, MV-22Bs from VMM-262 'Flying Tigers' assigned to the 15t Marine Air Wing delivered humanitarian aid and transported evacuees to Clark Air Base. The same squadron, as part of the 3rd Marine Expeditionary Brigade, was again involved in relief Operation Damayan, after Typhoon Haiyan/Yolanda struck the Philippines in November 2013.
Israel has reportedly been interested since 2011 in acquiring V-22s for the Csar role and the insertion and recovery of special forces. In January 2014 America's DSCA (Defense Security Cooperation Agency) notified Congress of a possible FMS (Foreign Military Sale) to Israel of six V-22B Block C aircraft in a package worth around $ 1.13 billion (a remarkable $ 188 million per aircraft). Included in the deal were 16 engines, plus "aircraft ferry services" and tanker support. Israel's urgent need for these aircraft is evidently such that they will be taken from existing American Department of Defense orders and ferried to Israel, presumably refuelled by US Air Force tankers.
The second export order is evidently to be for Japan, which has just launched a five-year (FY14-18) defence build-up programme, addressing concerns that include Chinese activities in the East China Sea. One long-running problem is that China (among several other territorial disputes with its neighbours) claims sovereignty over what it terms the Diaoyu Islands, which Japan calls its Senkaku. In addition, China's new East China Sea Air Defence Identification Zone overlaps with Japan's own Air Identification Zone. Japan's Defence Ministry in its latest National Defence Programme Guidelines has warned that China may "attempt to change the status quo by coercion':
Japan needs the ability quickly to insert forces from the new Gsdf amphibious brigade (which is being trained by the US Marine Corps) to any of the disputed islands, and the best way to do this is the V-22. The new MDTP (Mid-Term Defense Plan) states that the Asdf will acquire 17 V-22s, with the first order placed in April 2014.
The MDTP also states that Japan is considering the purchase of Lockheed Martin F-35Bs to operate from the 27,000-tonne DDH-183 Izumo- and 19,000-tonne DDH-181 Hyuga-class helicopter destroyers. Any such extension of the role of these ships would arguably make the purchase of additional V-22s more likely.
Following the Great East Japan Earthquake of 2011, that nation is also very aware of its vulnerability to large-scale disasters. It might therefore be conjectured that additional V-22s will be acquired later in this context.
The United Arab Emirates likewise has disputes over islands, in this case with Iran over three in the Persian Gulf, and this may motivate the purchase of V-22s. In addition, there are reports that the United Arab Emirates shares Israel's interest in the ability (in the event of war) to insert special forces into Iran to strike at mobile ballistic missile launch sites. Other countries interested in acquiring the V-22 are said to include Qatar and Saudi Arabia.
The versatility and spectacular performance improvement provided by the V-22 over a conventional helicopter, coupled with its good safety record in recent years, have provided a major boost for exports. They have also significantly enhanced prospects for the commercial 7,620-kilogram (8,164-kilogram in sto) tilt-rotor AgustaWestland AW609, which is expected to achieve European and US certification in 2017.
In addition, these factors have encouraged use of the tilt-rotor concept in the US Army's JMR (Joint Multi-Role) technology demonstration programme, the precursor of the FVL-M (Future Vertical Lift--Medium) programme to replace the Boeing AH-64 and Sikorsky UH-60. Tilt-rotors are used in two of the four competing designs: the Bell V-280 Valor and the Karem TR36D.
Caption: Somewhere in the Arabian Sea, MV-2213 serial 165849, c/n 0035, assigned to VMI14-261 'Raging Bulls: receives its final checks prior to take-off from--LHD-7, USS Iwo Jima. (US Navy).
Caption: On December 18,1958, US Army serial 54-148, the second Bell XV-3, originally designated XH-33-BF, became the first tilt-rotor to complete conversion from vertical take-off to wingbome flight. (Nasa/National Museum of the US Air Force).
Caption: The technology demonstrator that paved the way for the Bell Boeing V-22 was the Bell XV-15, which first flew on May 3, 1977 and set a speed record of 456 km/hr. Illustrated is the second aircraft, registration N703NA. (Nasa-Armstrong).
Caption: This pair of MV-22Bs from VMM-263, an air element of the 22nd Marine Expeditionary Unit, was pictured flying along the Egyptian coastline during Exercise Bright Star 2009. (US Marine Corps).
Caption: An MV-22B of VMM-263 taxies to the parking area after landing at Al Asad Air Base in the west of Iraq on September 4, 207. This was the first of ten Ospreys that ferried from LHD-1, USS Wasp, operating in the Persian Gulf. (US Marine Corps).
Caption: Some MV-22Bs wear the dark green paint scheme of Marine Helicopter Squadron One, HMX-1 "Nighthawks', tail code MX. The unit is based at Marine Corps Air facility Quantico, Virginia, and is tasked with VIP tireinsport and operational test and evaluation duties. (US Marine Corps).
Caption: The sun sets at St John's, Nova Scotia, behind a US Air Force CV-22B, one of four 8th SOS Ospreys deploying 9,800 kilometres from Hurlburt Field, Florida to Mali in Africa for Exercise Flintlock in 2008. (US Air Force Special Operations Command)
Caption: Proximity trials to assess the Osprey's tanker potential employed MV-22B BuAer 165942, c/n 0043, registration N204TR from Marine Tiltrotor Test & Evaluation Squadron VMX-22 Argonauts based at Mcas New River, North Carolina. The VW tail-code of the F/A-18 indicates VMFA-314 'Black Knights' from Mcas Miramar (Bell Boeing)
Caption: Military use of the V-22 gave credibility to the commercial AgustaWestland AW609 project, until 2011 the Bell/Agusta Aerospace BA 609. The first prototype, US registration N609TR, had its maiden flight on March 6, 2003. (Agusta Westland).
Caption: Bell's proposal for the US Army Joint Multi-Role (JMR) technology demonstration programme is the V-280 Valor, shown here in mock-up form. Note that the engines are fixed, partly to maximise field of fire from the cabin. (Bell Helicopter Textron)
Caption: Karem Aircraft is promoting the Optimum-Speed Tilt-Rotor (OSTR) concept, illustrated here by the company's TR75 proposal for the Joint Heavy Lift (JHL) programme. The smaller TR36D is proposed for JMR. (Karem Aircraft).
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|Title Annotation:||V-22 Market|
|Date:||Jun 1, 2014|
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