ABSTRACT
It has long been a dream of aircraft designers to create an airplane that not only can fly long ranges at high speeds and carry heavy cargo, but can also take off, hover and land like a helicopter. Such a plane would have the flexibility to handle many different types of military missions and would also have civilian and commercial uses. The V-22 Osprey is such a vehicle. This versatile craft has been developed for the military by Bell-Boeing aircraft. Through the use of a tilt rotor, the Osprey can take off and land like a helicopter, but convert to a turboprop airplane while in flight. The aircraft’s rotors can fold, and the wings can rotate so it can be stored on an aircraft carrier. The V-22 Osprey is a joint-service, medium-lift, multi-mission tilt-rotor aircraft developed by Boeing and Bell Helicopters. Boeing is responsible for the fuselage, landing gear, avionics, electrical and hydraulic systems, performance and flying qualities. Bell Helicopter Textron is responsible for the wing and nacelle, propulsion, rotor, empennage (complete tail system), ramp, overwing fairing and the dynamics. The aircraft operates as a helicopter when taking off and landing vertically. The nacelles rotate 90 degrees forward once airborne, converting the aircraft into a turboprop aircraft. This paper briefly describes this tilt –rotor aircraft, its history its development and its working. It also peeps into the available models and their specifications. This paper also explains the future of this type of aircraft in civil transport and the military side.2.INTRODUCTION
The V-22 tilt rotor is a revolutionary, vertical and short take-off and land (V/STOL), multi-purpose aircraft with excellent high-speed cruise performance. This advanced technology rotorcraft performs a wide range of V/STOL missions as effectively as a conventional helicopter, while equally capable of achieving the long-range cruise efficiencies of a twin turboprop aircraft. Missions that cover large distances and that require vertical takeoffs and landings have challenged aeronautical pioneers since helicopters first proved their worth almost 50 years ago. The challenge has been to devise a vehicle that is faster, has more range, and is more cost effective than conventional helicopters.
Within this challenge, the Joint Services (USMC, USN, USAF, USA) specified in detail the operational requirements of the V-22. The joint requirement defined missions, airframe size constraints, payload handling, and other operational capabilities required to meet the needs of all the U.S. Military The V-22 Osprey is a revolutionary change. It has recently been acknowledged by the Department of Defense as one of only four truly Transformational systems. It brings capabilities not found in any helicopter – twice the speed, three times the payload and five times the range of the legacy helicopters that it replaces. Add the ability to fly two and a half times higher than those helicopters and you have an aircraft that is truly a leap ahead. These capabilities recognized in 18 major
studies and analyses, including seven. The V-22 Osprey is a revolutionary change. It has recently been acknowledged by the Department of Defense as one of only four truly Transformational systems. It brings capabilities not found in any helicopter – twice the speed, three times the payload and five times the range of the legacy helicopters that it replaces. Add the ability to fly two and a half times higher than those helicopters and you have an aircraft that is truly a leap ahead. These capabilities recognized in 18 major studies and analyses, including seven Cost and Operational Effectiveness Analyses (COEAs) performed by the U.S. Government. All these studies have shown that the Osprey is more cost effective than any helicopter, compound helicopter, or combination of helicopters. The Osprey will bring interoperability and vastly increased mission effectiveness to armed forces around the globe.
Designed to the most stringent set of requirements ever imposed on a rotary wing aircraft, the V-22 successfully demonstrated that it was both effective and suitable for the Marine Corps mission during Operational Evaluation (OPEVAL) Phase I. After two years of additional, detailed flight testing, it will undertake OPEVAL Phase II, and enter into Full Rate Production in 2005. The V-22 is currently in Low Rate Initial Production (LRIP). V-22 design criteria answered questions about safety, reliability, readiness, all weather, survivability, crashworthiness, and performance; shipboard compatibility was designed in at the outset. The modern avionics suite of communication, navigation and penetration aids are fully integrated and redundant, where necessary, to ensure successful mission completion. Other design considerations include meeting guarantees for weight and performance, graceful handling of engine failures, crashworthiness, emergency egress, and maintenance or repair accessibility. The V-22 uses proven technology to meet all of these requirements and more.
3.ADVANTAGES OVER AEROPLANE AND HELICOPTER
The Osprey has two, large, three-bladed rotors that rotate in opposite directions and produce lift. Because the rotors turn in opposite directions, there is no need for a tail rotor to provide stability as in a helicopter. The wing tilts the rotors between airplane and helicopter modes and generates lift in the airplane mode. The Osprey can convert smoothly from helicopter mode to airplane mode in as few as 12 seconds. Through the use of a tilt rotor, the Osprey can take off and land like a helicopter, but convert to a turboprop airplane while in flight. The aircraft’s rotors can fold, and the wings can rotate so it can be stored on an aircraft carrier.
V22 transitioning from helicopter to aircraft
The major advantages of the Osprey over a helicopter are: Longer range – The Osprey can fly from 270 to 580 miles (453 to 933 km). Higher speed – The Osprey’s top speed is 315 mph (507 kph), which is twice as fast as a helicopter’s top speed. Increased cargo capacity – The Osprey can carry 10,000 pounds (4,536 kg) of cargo or 24 troops.
The advantage of the Osprey over an airplane is that it can take off, hover and land like a helicopter. This makes is more versatile than an airplane for such missions as moving troops to remote areas, especially those without landing strips, or conducting long-range rescue operations at sea.
4.HISTORY
The world has had a large number of long runways in almost every corner since the Second World War, but today military experts are trying to get away from the use of them, in fear of the havoc that might be caused by their destruction in wartime. To gain this end, a number of VTOL (Vertical Take-Off and Landing) aircraft, from fighters to transport aircraft, have been designed, tested and flown. One of the most successful of these is the Bell/Boeing V-22 Osprey. To provide the necessary background, its predecessors and proponents are described here as well.
The world’s first experiment in VTOL fixed-wing (that is, not a helicopter) aircraft was Germany’s Bachem Ba.349 Natter (Adder) fighter, powered by rocket engines and mounted on its tail for take-off. It was a last-ditch attempt to stop the Allied bombers from pounding the Third Reich to pieces. There was no provision for a landing, vertical or otherwise: the pilot was to aim the aircraft at a bomber and take to his parachute. The Natter was never used: Allied tanks captured the 36 airframes that achieved completion. The captured Natters were examined carefully by the Allied Intelligence services. Like many of the other “bizarre” ideas of the Germans in the latter stages of the war, it was well worth trying, and had great potential if given enough time, money and labour to get it going. The work was done in America. Two VTOL fighters were designed for the US Navy, the Convair XFY-1 Pogo and the Lockheed XFV-1 Salmon. Like the Natter they used tail-sitting arrangements, but instead of the rocket engine, which uses its fuel at an exorbitant rate, they used an efficient turboprop. To cancel the powerful torque, two propellers were fitted, rotating in opposite directions, on the same engine shaft. While the VTOL fighter idea was (and still is) a very good one, both the Pogo and Salmon were cancelled due to the seemingly insurmountable technical difficulties.
The Ryan X-13 Vertijet followed the same lines, with a Rolls-Royce Avon engine for thrust, and a truck-mounted trapeze for landing. Its success, suggested a cynical observer, would be due to the great amusement of the enemy, who would be so “doubled up with laughter” as to “be unable to get off a shot”! The Tail-Sitting method was obviously not possible: with a limited downward/backward view, the prospect of a landing on a rolling aircraft carrier deck, or a shell-damaged patch of concrete near a hidden air base, would make even the best military pilots shudder. A better idea is to have only the thrust producing units tilting. Tilt-rotors and tilt-wings do much better.
The first experimental tilt-rotor transport was the Bell XV-3. It arose from a USAF competition, combined with vague ideas in some of Bell’s engineers’ minds. The first test flight was a mere hovering. Then, on 18 December 1958, the first conversion from helicopter to aeroplane occurred. History was made. Flights and testing continued until 1966, when the program proved that while the idea was practical, there were many problems to overcome. Before the shelving of the XV-3 program, the Army asked Bell to design another “convertiplane”, the XV-15, of which two prototypes were built. On 24 July 1979 the XV-15 became the first aircraft to convert from helicopter to aeroplane and back again. Later is set a world speed record for a rotorcraft at 346mph in level flight. The XV-15 program was expanded into the JVX program, common to all the US forces, and the aircraft renamed the V-22 Osprey. It is very distinctive with its square fuselage, bulged at the bottom in the center, broad stubby wings with engines on the tips, massive prop-rotors, and twin tails.
The six prototype V-22 Ospreys were used only for experiments. It was proven that using V-22s would speed up a Marine operation that would previously be done by CH-53E Super Stallions. The trials were so convincing that the Navy and the Air Force also ordered versions. The Marines’ MV-22A (Multimission VTOL) has the ability to carry 24 fully armed troops or 6000lb of cargo at a cruising speed of 288mph and range of 460 miles. Around 500 are expected to be ordered to replace the CH-46 Sea Knight and CH-53E Super Stallion.
The US Navy has ordered two versions. The first, the HV-22A (Search and rescue VTOL) has one of the toughest jobs available to an aircraft. 55 are on order, with the same top speed of the MV-22A but 70 more miles of combat radius. Although based on Aircraft Carriers, they will be able to operate from frigates, as most helicopters can today. The second Navy version, the SV-22A (Anti-Sub VTOL), will counter the Navy’s biggest headaches, enemy submarines. The S-3 Vikings are running out of airframe life, so the Anti-Submarine Warfare Ospreys will replace them, with the added bonus of hovering capability (currently provided only in the SH-60 Sea Hawk helicopters, which have very short range). It will carry torpedoes and anti-ship missiles, as well as search equipment, so it can act as a killer as well as a hunter.
The USAF plan to order 55 CV-22A’s (Cargo VTOL), capable of carrying 12 fully armed troops or up to 2990lb of cargo. The same speed is coupled with a range of 600 miles. The exciting world of vertical take-off is promising, and has enormous potential. When eventually the world’s experts come to their senses and require fast VTOL transports, the V-22 will surely come to the fore.
The Osprey is a type of vertical takeoff and landing (VTOL) aircraft with a tilt-rotor design. The VTOL concept is an old idea stemming from the German air force at the end of World War II. After the war, the U.S. Navy developed two experimental VTOL fighter aircraft, the Pogo and the Salmon. However, the programs were cancelled because of technical difficulties. In 1958, the U.S. Air Force developed the Bell XV-3, which was the first successful VTOL to hover (it was not tested in airplane flight).
Tilt-rotor aircraft: Bell XV-3 (right) and Bell XV-15 (left)
5.DEVELOPMENT OF THE FLIGHT
In accordance with the approved TEMP, OT-IIC was conducted in six phases at NAS Patuxent River and Bell-Boeing facilities in Pennsylvania and Texas, from October 1996, through May 1997.
Significant flight limitations were placed on the FSD V-22 in OT&E to date, including:
- not cleared to hover over unprepared landing zones until OT-IIC
- no operational internal or external loads or passengers
- moderate gross weights only
- not cleared to hover over water.
The OT-IIB report expressed serious concerns regarding the potential downwash effects, and recommended further investigation. While a limited assessment of downwash and workaround procedures was included in OT-IIC, complete resolution of the downwash issue will not be possible until the completion of OPEVAL, just prior to milestone III in 1999.
The Navy is conducting an aggressive LFT&E program on representative V-22 components and assemblies, in compliance with a DOT&E-approved alternative LFT&E plan. The V-22 program was granted a waiver from full-up, system-level LFT&E in April, 1997. The vulnerability testing that the program is performing is appropriate and will result in the improvement of aircraft survivability. The V-22 program TEMP was last approved by DOT&E on September 28, 1995, and will be updated prior to each OT&E period scheduled.
With DOT&E encouragement, the Navy greatly expanded the scope of OT-IIC to get better insight into the effectiveness and suitability of the EMD design. The results, while not yet conclusive regarding the potential operational effectiveness and suitability of operational aircraft, were encouraging. The six phases of the OT-IIC Assessment included: (1) shipboard assessment, (2) maintenance demonstrations, (3) tactical aircraft employment via FSD aircraft and manned flight simulator, (4) operational training plans, (5) program documentation review, and (6) software analysis.
In assessing the operational effectiveness and suitability COIs, COMOPTEVFOR and AFOTEC found that in most cases, only moderate risk exists that the COIs will not be satisfactorily resolved when development is complete. Enhancing features observed during OT-IIC included aircraft payload, range and speed characteristics better than the stated operational requirements. In addition, reliability, availability and maintainability of the EMD aircraft appeared to be significantly improved over those of the FSD aircraft.
Several areas of concern first discovered in OT-IIA or OT-IIB remain unresolved because of limitations to the EMD flight test operations. These concerns include severe proprotor downwash effects during personnel insertion and extraction via hoist or rope. In addition, concerns exist in the areas of communications, navigation , and crew field of view. New concerns arising from OT-IIC regarding the EMD schedule are being addressed by the program manager. Also, the reliability and maintainability of a few subsystems will require management attention. Despite these concerns, the V-22 design remains potentially operationally effective and suitable.
The aircraft’s prime contractors include Boeing Company’s helicopter division in Ridley Park, PA, and Bell Helicopter Textron of Fort Worth TX.
In 1986 the cost of a single V-22 was estimated at $24 million, with 923 aircraft to be built. In 1989 the Bush administration cancelled the project, at which time the unit cost was estimated at $35 million, with 602 aircraft. The V-22 question caused friction between Secretary of Defense Richard B. Cheney and Congress throughout his tenure. DoD spent some of the money Congress appropriated to develop the aircraft, but congressional sources accused Cheney, who continued to oppose the Osprey, of violating the law by not moving ahead as Congress had directed. Cheney argued that building and testing the prototype Osprey would cost more than the amount appropriated. In the spring of 1992 several congressional supporters of the V-22 threatened to take Cheney to court over the issue. A little later, in the face of suggestions from congressional Republicans that Cheney’s opposition to the Osprey was hurting President Bush’s reelection campaign, especially in Texas and Pennsylvania where the aircraft would be built, Cheney relented and suggested spending $1.5 billion in fiscal years 1992 and 1993 to develop it. He made clear that he personally still opposed the Osprey and favored a less costly alternative.
The program was revived by the incoming Clinton administration, and current plans call for building 458 Ospreys for $37.3 billion, or more than $80 million apiece, with the Marines receiving 360 Ospreys, the Navy 48 and the Air Force 50. The first prototype flew in 1989. As of early 2000 three test aircraft had crashed: no one was killed in the 1991 crash, an accident in 1992 killed seven men, and the third in April 2000 killed 19 Marines.
6.WORKING SYSTEMS
Like any aircraft, the Osprey has the following systems:
- Propulsion – generate power and lift to propel the aircraft
- Fuel
- Cockpit controls
- Communications – allow for communication with air controllers and military operations
- Payload – carry cargo
- Stowage – especially important when it’s stored on an aircraft carrier
Osprey’s external features
PropulsionAs mentioned above, the Osprey has two rotors with three-bladed, 38-ft (11.6-m) propellers. Each propeller is driven by an Allison AE 1107C turbo shaft engine that is capable of producing over 6,000 horsepower. Each engine drives its own rotor and transfers some power to a mid-wing gear box. This gearbox drives the tilting mechanism. In the event of an engine failure, the Osprey is capable of running on only one engine. In this case, power from the remaining engine is distributed to the two rotors through an interconnecting drive shaft. . A transmission interconnect shaft provides single-engine operation. The thermal signature of the aircraft is minimized with an AiResearch infrared emission suppression unit, installed on the nacelles near the engine exhaust. The entire rotor, transmission and engine nacelles tilt through 90° in forward rotation and are directed forwards for forward flight, and through 7° 30′ in aft rotation for vertical take-off and landing.
 Photo courtesy U.S. Navy Osprey propulsion |
Fuel
The Osprey has 16 fuel tanks, 10 integrated into the wings and six in the fuselage. The feed tanks directly supply the engines with fuel from the other tanks, and fuel transfer is automatic. As the fuel flows from the tanks, pressurized nitrogen gas fills the tanks to reduce the possibility of fire. Depending upon the configuration of the Osprey, it can hold from 1,450 to 3,640 gallons (5,489 to 13,779 liters) of fuel.
Photo courtesy U.S. Navy
Osprey fuel tanks
Cockpit Controls
The cockpit of the Osprey holds a pilot and co-pilot. In addition, there is a fold-down seat in the center behind the pilots for a flight engineer. The instrument panels have multi-functional displays, similar to the new glass cockpit of the space shuttle. The displays hold information about the engines (such as oil pressure, temperatures and hydraulic pressures) and flight (such as fuel data, attitude and engine performance). There are also keypads used to interact with the flight computer and sticks used to control the flight maneuvers.
Osprey control panels
Communications
The Osprey is equipped with multi-band radios (AM, FM, UHF, VHF) for voice transmission and radio reception. It also has navigational beacons and radios, radar altimeters and an internal intercom/radio system for communications among the crew and troops onboard.
 Photo courtesy U.S. Navy Osprey control panels |
Payload
The Osprey can hold up to 24 troops and carry up to 20,000 lb (9,072 kg) in its cargo bay, which is 5.7 ft wide by 5.5 ft high by 20.8 ft long (1.72 x 1.68 x 6.35 m). The cargo bay has fold-down seats along the walls and a ramp that is used to load or deploy cargo and troops. Deployment can also take place in the air by parachute. In addition to the 20,000-lb load in the cargo bay, the Osprey has an external hook-and-winch system that allows it to carry up to 15,000 lbs (6,803 kg) of cargo in tow.
Stowage
When the Osprey lands on the deck of a ship, it can be folded up for down-time. The blades and the wings are both foldable.
The other equipments of V-22 Osprey are:
GUN – The aircraft will be equipped with a 12.7mm turreted gun system, which will be supplied by General Dynamics.
SENSORS -The US Air Force and US Navy variants are equipped with a Raytheon AN/APQ-186 terrain-following, multi-mode radar. The helicopter night-vision system is the Raytheon AN/AAQ-16 (V-22) FLIR, which is mounted on the nose. This system contains a 3-5 micron indium antimonide staring focal plane array.
COUNTERMEASURES -The aircraft’s electronic warfare suite includes Lockheed Martin’s AN/AAR-47 missile warning system, which consists of four electro-optic sensors with photomultipliers, a signal processing unit and a cockpit display. The aircraft is also equipped with a radar and infrared threat warning system and chaff and flare dispensers with 60 rounds of dispensables. The CV-22 will have the Suite of Integrated Radio Frequency Measures (SIRFC), being developed by ITT Avionics.
7.HOW OSPREY FLIES
To understand how the Osprey flies, the basic thing to understand is that airplane wings create lift by deflecting air downward, benefiting from the equal and opposite reaction that results. Helicopters do the same thing with blades, which are rotating wing shapes like the airfoils of an airplane wing. Helicopter blades are thinner and narrower than airplane wings because they have to rotate so fast. These rotating wings are mounted on a central shaft. When the shaft is spun, lift is created.
V22 Osprey transitioning from aeroplane to helicopter
When the Osprey is ready to take off, its rotors are in a vertical position. With the rotors mounted on the wings, it looks like a two-bladed helicopter. When the Osprey is in helicopter mode (on takeoff, landing and when hovering), the rotors generate lift. While in flight, the Osprey’s rotors move down to a horizontal position. In this position, it is the wings that generate lift, like on a traditional airplane, and the rotors function as they do in a propeller aircraft. The Osprey lands like a helicopter by reversing the process, raising the rotors from a horizontal to a vertical position
8.SPECIFICATIONS
| Primary function | Amphibious assault transport of troops, equipment and supplies from assault ships and land bases |
| Prime Contractor(s) | Boeing Defense and Space Group, Philadelphia, PA Bell Helicopter Textron, Ft Worth, TX Allison Engine Company, Indianapolis, IN |
| Description | The V-22 Osprey is a multi-engine, dual-piloted, self-deployable, medium lift, vertical takeoff and landing (VTOL) tiltrotor aircraft designed for combat, combat support, combat service support, and Special Operations missions worldwide. It will replace the Corps’ aged fleet of CH-46E and CH-53D medium lift helicopters |
| Variants | CV-22 will be utilized by the Air Force for their Special Operations missions maintaining maximum commonality with the MV-22. Aircraft avionics peculiar to the Air Force unique mission requirements constitute aircraft differences. HV-22 will be used Navy the for Combat Search and Rescue and fleet logistics support. |
| Length | 57′ 4″ – Spread 63′ 0″ – Folded |
| Width | 84′ 7″ – Spread 18′ 5″ – Folded |
| Height | 22′ 1″ – Spread 18′ 1″ – Folded |
| Takeoff Weights | 47,500 lb Vertical Takeoff/Landing (VTOL) 55,000 lb Short Takeoff/Landing (STOL) 60,500 lb Self Deploy STO |
| Range | 200nm Pre-Assault Raid with 18 troops 200nm Land Assault with 24 troops 50 nm (x2) Amphibious Assault 500 nm Long Range SOF Missions (USAF/CV-22) 2100 nm Self Deploy (with one refueling) 50 nm External Lift Operations with 10,000 lb load |
| Cruise Airspeed | 240 kts (MV-22) 230 kts (CV-22) |
| Milestones | First Flight – March 19, 1989 First Sea Trials – USS Wasp (LHD-1), December, 1990, Aircraft # 3 & 4 First EMD Flight – February 5, 1997 2nd Sea Trials – USS Saipan (LHA-2), January, 1999, Aircraft #10 First LRIP Delivery – May 25, 1999 OPEVAL – Scheduled October, 1999 to May, 2000 Full Rate Production – First Quarter, 2001 IOC – USMC – 2001; US SOCOM – 2004 |
| Unit Cost | $40.1M (Total Program Recurring Flyaway, Constant Year, FY94$) |
| Number Procured | 12 MV-22(authorized through FY98) |
| Planned Inventory | 348 MV-22 (USMC) 50 CV-22 (USAF) 48 HV-22 (USN) |
| Deployed to | MV-22s will be deployed to all Marine Corps medium lift active duty and reserve tactical squadrons, the medium lift training squadron (FRS), and the executive support squadron (HMX) |
| Avionics | Dual 1553B data bus |
| | Dual 64 bit mission computers with ADA |
| | Night vision compatible, multi-function display cockpit |
| | Inertial navigation/TACAN/global positioning system |
| | Forward looking infra-red FLIR |
| | Digital map |
| | Radar altimeter |
| | IFF/SIF Identification, friend or foe/selective identification facility |
| | VOR/ILS/MB VHF omnidirectional radio range/instrument landing system/magnetic bearing |
| | SATCOM satellite communications |
| | Digital data burst, low probability of intercept communications |
| | Troop Commander’s COMM |
| | Flight incident recorder |
| | Radar/missile/laser warning receivers |
9.FUTURE OF TILT ROTOR AIRCRAFT
The recent developments in tilt rotor aircraft is the development of civil aircraft like the BA609.
Here is the story of the passenger aircraft which will bring about revolution in aircraft industry.
A new chapter in aviation history opened on March 7, 2003 with the maiden flight of the world’s first civil tilt-rotor, the Bell/Agusta Aerospace BA609. The nine-passenger aircraft, jointly developed by Bell Helicopter, a Textron company and by Agusta, an AgustaWestland company, hovered at an altitude of 50 feet, performed left and right peddle turns, both forward and aft flight maneuvers, four take-offs and landings, nacelle position changes and stability testing for 36 minutes before setting down. The first flight followed seven weeks of ground runs and taxi testing conducted at Bell’s Flight Re-search Center.
With its rotors in the vertical position, the tiltrotor is able to take-off, land and hover like a traditional helicopter. When the rotors are tilted forward to the horizontal position, the aircraft is
able to fly similar to a turboprop fixed-wing airplane. The transition from helicopter
mode to airplane mode takes 20 seconds, as does the transition from airplane mode to helicopter mode. Following the first flight the BA609 successfully completed the initial phase of flight testing, with a total of 14 flight hours. Throughout this phase the flying has been in helicopter mode with the rotors operating at or near the vertical position, speeds of 100 knots have been
achieved with Short Take Off and Landings up to 40 knots and 35 knots side-ward and rearwards flight. The BA609 successfully performed all the test points, many with results in excess of those predicted. The BA609 is expected to be FAA certified in 2007. Bell/Agusta will pro-duce a total of four prototype tiltrotor air- craft for flight testing. Final assembly for
production aircraft will take place at Bell’s Amarillo, Texas, facility with another assembly
line to be established at the Agusta plant in Italy. Fuji Heavy Indus-tries of Japan will build all of the production fuselages for the BA609. All parts and components for both lines will come
from the exact same source yielding air-craft that will be identical whether assembled
in Italy or Texas . Bell/ Agusta Aerospace Company headquarters is located at Alliance Air-port in Fort Worth, Texas. BA 609 customer training will be conducted at this location, which will also serve as a delivery center. The BA609 will cruise at 275 knots with a maximum unrefueled range of 750 nautical miles, 1,000 nautical miles with auxiliary fuel tanks. The air-craft in standard configuration will be fully pressurized and de-iced.
| PROPULSION: Power plants (2) | Pratt & Whitney of Canada PT6C-67A Turbo shaft | |||
| ENGINE RATINGS: | | | | |
| | | HP | | KW |
| Take off Power/Max Continuous Power (each) | | 1940 | | 1447 |
| | | | | |
| *PERFORMANCE: (ISA, MTOW) | | | | |
| | | | | |
| Max. Cruise Speed | | 275 kn | | 509 Km/hr |
| VNE (Never exceed velocity) | | -NA- | | -NA-. |
| Rate of Climb TOP AEO | | 1500 ft/min | | 7.6 m/sec |
| HOGE TOP AEO | | 5000 ft | | 1524 m |
| Max. Range – No reserve | | 750 NM | | 1,389 Km |
| Max. Endurance – No reserve | | 3.0 hrs | | 3.0 hrs |
| Service ceiling (approximate) | | 25,000 ft | | 7,650 m |
| OEI Service ceiling | | 16,000 ft | | 4,877 m |
| Cabin pressurization | | 5.5psi | | |
| *pending certification | | | | |
| | | | | |
| DIMENSIONS: | | Ft | | M |
| Length overall | | 44 | | 13.31 |
| Width overall (rotors turning) | | 60 | | 18.29 |
| Proprotor diameter | | 26 | | 7.93 |
| | | | | |
| Number of blades per rotor | | 3 | | |
| | | | | |
| Internal cabin size (L x W x H): | | 161″ x 58″ x 56″ | | 4.09m x 1.47m x 1.42m |
| Cabin door (width only). Note: Sliding door not available at initial deliveries. | | baseline 30″ optional door: 38″ | | baseline 0.76m optional door: 0.96m |
| | | | | |
| Weights: | | Lb | | Kg |
| Maximum Take-off | | 16,800 | | 7,258 |
| Maximum Useful load | | 5,500 | | 2,50 |
| | | | | |
| Capacities: | | | | |
| Required crew | | 1-2 | | |
| Passenger seating | | 6-9 | | |
| Baggage compartment | | 50 cu ft | | 1.41 cu m |
10. CONCLUSION
The V-22 is a joint service, multi-mission aircraft with vertical take-off and landing (VTOL) capability. It performs VTOL missions as effectively as a conventional helicopter while also having the long-range cruise abilities of a twin turboprop aircraft.
It has been used primarily in military applications due to its high load carrying capacity. It has been widely used by the navy , army ,marine and the customs. The Marine Corps version, the MV-22A, is an assault transport for troops, equipment and supplies, and is capable of operating from ships or from expeditionary airfields ashore. The Navy’s HV-22A provides combat search and rescue, delivery and retrieval of special warfare teams along with fleet logistic support transport. The Air Force CV-22A conducts long-range special operations missions. Now in the future it will be used for civil transport also .all round of developments is going on to public transport. Maybe one day it will replace the present day helicopters and aircrafts. Let us wait and see.
BIBLIOGRAPHS
JOURNAL OF THE AMERICAN HELICOPTER SOCIETY
TILT ROTOR TECHNOLOGY -paper by Jim Garamone
NEWSLETTER OF THE PRATT WHITNEY COMPANY
JOURNAL OF MILITARY TRANSPORT
FACT FILE OF THE V 22 OSPREY
www.defencejournals.com
www.helicopters.com
www.vtols.com
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