C-17 Globemaster III
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Image:C-17 1.jpg Image:C-17 4.jpg The C-17 Globemaster III is a strategic airlifter manufactured by Boeing Integrated Defense Systems, and operated by the United States Air Force and the Royal Air Force.
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Mission
The C-17 Globemaster III is the newest purpose-built cargo aircraft to enter the U.S and Western air forces. It is capable of rapid strategic delivery of troops and all types of cargo to main operating bases or directly to forward bases in the deployment area. This aircraft is also capable of performing tactical airlift and airdrop missions when required. The inherent flexibility and performance of the C-17 force improves the ability of the total airlift system to fulfill the worldwide air mobility requirements of the United States.
The ultimate measure of airlift effectiveness is the ability to rapidly project and sustain an effective combat force close to a potential battle area. In recent years the size and weight of U.S. mechanized firepower and equipment have grown, which has significantly increased air mobility requirements, particularly in the area of large or heavy outsize cargo. As a result, newer and more flexible airlift aircraft such as the C-17 are needed to meet potential armed contingencies, peacekeeping or humanitarian missions worldwide.
Features
The C-17 is powered by four, fully reversible, F117-PW-100 turbofan engines (the Department of Defense designation for the commercial Pratt and Whitney PW2040, currently used on the Boeing 757.) Each engine is rated at 40,440 lbf (180 kN) of thrust. The thrust reversers direct the flow of air upward and forward. This facilitates a decreased rate of ingestion of foreign object debris (FOD) as well as reverse thrust capable of backing the aircraft. Additionally, the C-17's thrust reversers can be used at idle-reverse in flight for added drag in maximum-rate descents.
The aircraft is operated by a minimum crew of three (pilot, copilot, and loadmaster). Cargo is loaded onto the C-17 through a large aft door that accommodates both rolling stock (vehicles, trailers, etc.) and palletized cargo. The cargo floor has rollers (used for palletized cargo) that can be flipped to provide a flat floor suitable for rolling stock. One of the larger pieces of rolling stock that this aircraft can carry is the 70-ton M1 main battle tank.
Maximum payload capacity of the C-17 is 170,900 lb (77,500 kg), and its maximum gross takeoff weight is 585,000 lb (265,350 kg). With a payload of 160,000 lb (72,600 kg) and an initial cruise altitude of 28,000 ft (8,500 m), the C-17 has an unrefueled range of approximately 2,400 nautical miles (4,400 km) on the first 71 units, and 2,800 nautical miles (5,200 km) on all subsequent units, which are extended-range models with an additional fuel tank in the center wing box. Its cruise speed is approximately 450 knots (833 km/h) (.74 Mach). The C-17 is designed to airdrop 102 paratroopers and equipment.
The C-17 is designed to operate from runways as short as 3,000 ft (900 m) and as narrow as 90 ft (27 m). In addition, the C-17 can operate out of unpaved, unimproved runways (although this is rarely done due to the increased possibility of damage to the aircraft). The thrust reversers can be used to back the aircraft and reverse direction on narrow taxiways using a three-point (or in some cases, multi-point) turn maneuver.
Background
Image:Air force globemasters unload supplies in mississippi aug 31 2005.jpg In the 1970s, USAF began looking for a replacement for the C-130 Hercules tactical airlifter. The Advanced Medium STOL Transport (AMST) competition was held, with Boeing proposing the YC-14, and McDonnell Douglas proposing the YC-15. The AMST competition was cancelled before a winner had been selected.
By the early-1980s, the USAF found itself with a very large, but aging fleet of C-141 Starlifters. Some of the C-141s had major structural problems as a result of heavy use. Compounding matters, USAF historically never possessed sufficient strategic airlift capabilities to fulfill its airlift requirements. In response, McDonnell Douglas elected to develop the YC-15 as the basis for a new aircraft. This aircraft, by then designated the C-17A Globemaster III, was ordered in August 1981. The new aircraft differed in having swept wings, increased size, and more powerful engines. This would allow it to perform all work performed by the C-141, but to also fulfill some of the duties of the C-5 Galaxy, so that the C-5 fleet would be freed up for larger, more outsize cargo.
Development continued until December, 1985 when a full-scale production contract was signed. Its maiden flight was on September 15, 1991 from the McDonnell-Douglas west coast plant in Long Beach, California. This aircraft (T-1) and five more production models (P1-P5) participated in extensive flight testing and evaluation at Edwards AFB. Soon after the C-17 reached production, McDonnell Douglas was acquired by its former competitor, Boeing.
USAF background
The first production model was delivered to Charleston Air Force Base, S.C., on July 14, 1993. The first squadron of C-17s, the 17th Airlift Squadron, was declared operationally ready on January 17, 1995.
The Air Force originally programmed to buy a total of 120 C-17s, with the last one being scheduled for delivery in November 2004. The fiscal 2000 budget funded another 14 aircraft for Special Operations Command. Basing of the original 120 C-17s is planned for Charleston AFB; McChord AFB (first aircraft arrived in July 1999); Altus AFB; and at an Air National Guard unit in Jackson, Miss. Basing of the additional 14 aircraft to McGuire AFB NJ Elemendorf AK Hickham HI Dover AFB DE and Travis AFB CA. An additional 60 units were ordered in May of 2002. In FY2006 Eight C-17s were delivered to the 452d Air Mobility Wing at March ARB (Air Reserve Base), CA. These C-17s are the only ones strictly under direct command of the Air Force Reserve.
The USAF originally intended to acquire about 350 units, though this was reduced at the end of the Cold War. However, USAF has been so pleased and amazed with the aircraft that it is entirely possible that the C-17 will be ordered in greater quantities than originally envisioned, with current orders standing at 180. There has been debate regarding follow-on orders for the C-17, with the Air Force requesting line shutdown, and members Congress attempting to reinstate production. Furthermore, in FY2007, the Air Force requested $1.6 billion to deal with what it termed "excessive combat use" on operational airframes.<ref name="avweek_20060313">Fulghum, D., Butler, A., Barrie, D.: "Australia Picks C-17.", Aviation Week & Space Technology. March 13, 2006, page 43.</ref>
RAF background
Boeing has actively marketed the C-17 to many European nations including Belgium, France, Spain and the United Kingdom. Of these, the UK was always seen as the most likely customer given its increasingly expeditionary military strategy and global commitments. The Royal Air Force has established an aim of having interoperability and some weapons and capabilities commonality with the United States Air Force. The UK's 1998 Strategic Defence Review identified a requirement for a strategic airlifter following the protracted procurement of the European airlifter, the Airbus A400M. The Short-Term Strategic Airlift (STSA) competition commenced in September of that year. The UK cancelled the competition in August 1999 recognizing that the C-17 was the only aircraft that met its demanding specifications.
The UK Defence Secretary, Geoff Hoon, announced in May 2000 that the RAF would lease four C-17s at an annual cost of £100 million<ref name="avweek_20060313">filler</ref> from Boeing for an initial seven years with an optional two year extension. At this point the RAF would have the option to buy the aircraft or return them to Boeing. The UK committed to upgrading the C-17s in line with the USAF so that in the event of them being returned to Boeing the USAF could adopt them.
The first C-17 was delivered to the RAF at Boeing's Long Beach facility on May 17, 2001 and flown to RAF Brize Norton by No. 99 Squadron which had previously trained with USAF crews to gain competence on the type. The RAF's fourth C-17 was delivered on August 24, 2001. The RAF aircraft were some of the first to take advantage of the new centre wing fuel tank.
The RAF declared itself delighted with the C-17 and reports began to emerge that they wished to retain the aircraft regardless of the A400M's progress. Although the C-17 fleet was to be a fallback for the A400M, the UK announced on July 21, 2004 that they have elected to buy their four C-17s at the end of the lease, even though the A400M is moving towards production. They will also be placing a follow-on order for one aircraft, though there may be additional purchases later.<ref name="gdr_2003">"RAF's Globe Master." Global Defence Review. 2003.</ref> While the A400M is described as a "strategic" airlifter, the C-17 gives the RAF true strategic capabilities that it would not wish to lose, for example a maximum payload of 77,000 kg compared to the Airbus' 37,000 kg. The fifth aircraft has not yet been ordered, but must be completed by mid-2006 to maintain deposits and the production slot.<ref name="avweek_20060313">filler</ref>
In RAF service the C-17 has not been given an official designation (e.g. C-130J referred to as Hercules C4 or C5) due to its leased status, but is referred to simply as the C-17. Following the end of the lease period the four aircraft will assume an RAF designation, most likely "Globemaster C1." Presumably, should the additional aircraft enter service prior to this, it alone will carry the C1 designation for a time.
Luftwaffe background
The 2004 Indian Ocean earthquake and resultant tsunamis placed a strain on the global strategic airlifter pool. The impressive performance of the C-17 in USAF and RAF service have persuaded Germany to consider acquiring 2-4 C-17s for the Luftwaffe in a dry lease arrangement, at least until the A400M is available in 2009. German Foreign Minister Joschka Fischer stated in the German news magazine Der Spiegel that the government needed its own organic strategic transport capability to be able to respond to disasters in a better manner than it was able to for this incident. During the tsunami relief effort, Germany tried to acquire transport through its usual method of wet leasing Antonov airlifters via private companies, but found to its dismay that there were no available aircraft. While the stated goal of a C-17 lease would be to last until the A400M's arrival, it is always possible that the Luftwaffe may undergo an experience similar to that of the RAF, and elect to retain them.<ref name="expatica_bdr">"Berlin designates tsunami relief as aid." Expatica. January 17, 2005.</ref>
RAAF background
The Royal Australian Air Force was revealed in late 2005 to be considering four C-17s or eight A400Ms for strategic transport. Minister for Defence Robert Hill stated that the Australian Defence Force was considering such aircraft given inavailability of aircraft from partner nations and air freight companies. The C-17 was considered to be the favorite, due to being a "proven aircraft," as well as having earlier availability. One major requirement from the RAAF was the ability to airlift the Army's M1 Abrams main battle tanks; another requirement was immediate delivery. Though unstated, commonality with USAF and the RAF was considered to be of benefit as well. The service announced on March 2, 2006, that they were purchasing three aircraft, plus one option, with an entry into service date of 2006.<ref name="raaf_pr">"New Heavy Airlift Capability For The Royal Australian Air Force." RAAF press release. March 2, 2006.</ref><ref name="wsj_aussie_c17">"Australia To Spend Up To A$2B On Boeing C-17 Aircraft." The Wall Street Journal. March 2, 2006.</ref><ref name="avweek_20060313">filler</ref>
CF background
In a similar position to Germany, Canada has a long standing need for strategic airlift for humanitarian and military operations around the world. The Canadian Forces have followed the pattern of the Luftwaffe in using rented Antonovs for many of their needs including deploying the Disaster Assistance Response Team - DART to tsunami stricken Sri Lanka in 2005. For the early part of their deployment to Afganistan the CF had to rely on USAF C-17s to get heavy equipment in theatre.
The Canadian Forces Future Strategic Airlifter Project has studied alternatives including long-term leasing arrangements since 2002. The assumption was that the military was pushing for the C-17 even though the outright purchase of even a small number was considered beyond the reach of the current CF budget<ref name="casr_dnd101_FSL">"DND 101 - Airforce Future Strategic Airlifter Project."Canadian American Strategic Review 2005.</ref> . The current Conservative Government promised during the January 2006 federal election campaign to purchase 3 or 4 strategic airlifters which was thought to be thinly veiled reference to the C-17<ref name="conservative_defence_pt7">"Stephen Harper announces the new defence policy put forward by the Conservative Party of Canada – Pt 7."Canadian American Strategic Review December 22,2005.</ref> .
Recent media reports suggest that the purchase of up to six C-17s could be announced in the next Canadian federal budget, with reports also suggesting that these six aircraft could have fixed purchase dates as early as a year from now.<ref name="globeandmail_Hillier_plan_in_doubt">"Hillier's aircraft plan in doubt." The Globe and Mail April 21, 2006.</ref> The projected cost of this purchase would be C$1.2 billion and talks are in place with the U.S. government to allow for access to some of the C-17 delivery slots currently allocated to USAF, similar to an agreement in place with the Australian government.
Wartime usage
The C-17 was used to deliver military goods and humanitarian aid during Operation Enduring Freedom in Afghanistan as well as Operation Iraqi Freedom in Iraq by both services. On March 26, 2003, fifteen USAF C-17s participated in the biggest combat airdrop since Operation Just Cause in Panama in December, 1989: the night-time airdrop of 1,000 paratroopers from the 173rd Airborne Brigade occurred over Bashur, Iraq. It opened the northern front to combat operations and constituted the largest formation airdrop since World War II.
Units using the C-17
United States Air Force
Inventory: 71 C-17, 67 C-17ER (+42 C-17ER on order) (as of July 25, 2005)
Royal Air Force
Inventory: 4 C-17ER (+1 C-17ER on order)
Royal Australian Air Force
Inventory: 3-4 C-17ER on order
- No. 36 Squadron, probably based at RAAF Base Amberley.<ref name="raaf_newspaper_20060323">"Master plan for C-17s." Air Force News. Volume 48, No. 4, March 23, 2006 </ref>
Specifications (C-17)
Image:C-17 3-view.png Template:Airtemp
References
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External links
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fr:McDonnell Douglas C-17 Globemaster III ja:C-17 (輸送機) sl:McDonnell Douglas C-17 Globemaster III sv:Boeing C-17 Globemaster III zh:C-17运输机 es:C-17 Globemaster III