srijeda, 31. ožujka 2010.

A-6 Intruder

The Grumman A-6 Intruder was a twin jet-engine, mid-wing attack aircraft built in the United States by Grumman Aerospace. In service between 1963 and 1997, the Intruder was designed as an all-weather replacement for the piston-engined A-1 Skyraider medium attack aircraft. A specialized electronic warfarederivative, the EA-6B Prowler, remains in service as of 2009. As the A-6 was slated for retirement, its precision strike mission was taken over by the now retired F-14 Tomcat equipped with LANTIRN pod.
The Intruder was developed in response to a United States Navy specification for an all-weather carrier-based attack aircraft to serve as a replacement for the piston-powered, World War II–era A-1 Skyraider.Grumman was awarded the contract in 1957, and the resulting A2F-1 made its first flight on 19 April 1960.

The jet nozzles were originally designed to swivel downwards, but this was dropped from production aircraft. The pilot sits in the left seat, while the bombardier/ navigator sits to the right and below. A unique CRT gives a synthetic display of terrain ahead which, with the additional crew member, enabled low-level flying in all weather conditions.

The wing is very efficient at subsonic speeds compared to supersonic fighters such as the F-4 Phantom II, which are also limited to subsonic speeds when carrying a payload of bombs. A very similar wing would be put on pivots on Grumman's later supersonic swing-wing F-14 Tomcat, as well as similar landing gear. The Intruder was also equipped with the "Deceleron", a type of airbrake on the wings with two panels that open in opposite directions; in this case, one panel goes up, while another goes down.

Specifications (A-6E)

General characteristics

Performance

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utorak, 30. ožujka 2010.

B-52 Stratofortress

The Boeing B-52 Stratofortress is a long-range, subsonic, jet-powered strategic bomber operated by the United States Air Force (USAF) since 1955.

Beginning with the successful contract bid on 5 June 1946, the B-52 design evolved from a straight-wing aircraft powered by six turboprop engines to the final prototype YB-52 with eight turbojet engines. The aircraft first flew on 15 April 1952 with "Tex" Johnston as pilot.

Built to carry nuclear weapons for Cold War-era deterrence missions, the B-52 Stratofortress replaced the Convair B-36. Although a veteran of a number of wars, the Stratofortress has dropped only conventional munitions in combat. The B-52 carries up to 70,000 pounds (32,000 kg) of weapons.

The USAF has possessed B-52s in active service since 1955. The bombers flew under the Strategic Air Command until SAC was disestablished in 1992 and its aircraft absorbed into the Air Combat Command (ACC), until February 2010 becoming part of Air Force Global Strike Command (AFGSC). Superior performance at high subsonic speeds and relatively low operating costs have kept the B-52 in service despite the advent of later aircraft, including the Mach-3XB-70 Valkyrie, the supersonic B-1B Lancer, and the B-2 Spirit. In January 2005, the B-52 became the second aircraft, after the English Electric Canberra, to mark 50 years of continuous service with its original primary operator. (As of 2009, the list has added the Tupolev Tu-95, the C-130 Hercules, the KC-135 Stratotanker, and the Lockheed U-2.)

On 23 November 1945, Air Materiel Command (AMC) issued desired performance characteristics for a new strategic bomber "capable of carrying out the strategic mission without dependence upon advanced and intermediate bases controlled by other countries". The aircraft was to have a crew of five plus turret gunners, and a six-man relief crew. It was required to cruise at 300 mph (240 kn, 480 km/h) at 34,000 feet (10,400 m) with a combat radius of 5,000 miles (4,300 nmi, 8,000 km). The armament was to consist of an unspecified number of 20 mm cannon and 10,000 pounds (4,500 kg) of bombs. On 13 February 1946, the Air Force issued bid invitations for these specifications, with Boeing, Consolidated Aircraft, and Glenn L. Martin Company submitting proposals.

Only three of the 13 B-52As ordered were built. All were returned to Boeing, and used in their test program. On 9 June 1952 the February 1951 contract was updated to order the aircraft under new specifications. The final 10, the first aircraft to enter active service, were completed as B-52Bs.

Even while the Air Force works on new bombers scheduled for 2037 it intends to keep the B-52H in service until at least 2040, nearly 80 years after production ended. This will be an unprecedented length of service for a military aircraft. B-52s are periodically refurbished at the USAF maintenance depots such as Tinker Air Force Base,Oklahoma.

The USAF continues to rely on the B-52 because it remains an effective and economical heavy bomber, particularly in the type of missions that have been conducted since the end of the Cold War against nations that have limited air defense capabilities. The B-52's capacity to "loiter" for extended periods over (or even well outside) the battlefield, while delivering precision standoff and direct fire munitions, has been a valuable asset in conflicts such as Operation Iraqi Freedom.

The speed of the B-1 Lancer and the stealth of the B-2 Spirit have only been useful until enemy air defenses were destroyed, a task that has been swiftly achieved in recent conflicts. The B-52 boasts the highest mission capable rate of the three types of heavy bombers operated by the USAF. Whereas the B-1 averages a 53% ready rate, and the B-2 achieved a 26%, the B-52 averages 80% as of 2001.

Additionally, a proposed variant of the B-52H was the EB-52. This version would have modified and augmented 16 B-52H airframes with additional electronic jamming capabilities. This new aircraft would have given the USAF an airborne jamming capability that it has lacked since retiring the EF-111 Raven. The program was cancelled in 2005 following removal of funding for the stand-off jammer. The program was revived in 2007 but funding was again canceled in early 2009.

Specifications (B-52H)

General characteristics

Performance

Armament

  • Guns: 1× 20 mm (0.787 in) M61 Vulcan cannon in a remote controlled tail turret, removed from all current operational aircraft
  • Bombs: Approximately 70,000 pounds (31,500 kg) mixed ordnance -- bombs, mines, missiles, in various configurations[6]

Avionics

  • Electro-optical viewing system that uses platinum silicide forward-looking infrared and high resolution low-light-level television sensors
  • Sniper Advanced Targeting Pod

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nedjelja, 28. ožujka 2010.

McDonnell Douglas DC-10


The McDonnell Douglas DC-10 is a three-engine widebody airliner, with two engines mounted on underwing pylons and a third engine at the base of thevertical stabilizer. The DC-10 has range for medium to long haul flights. The model was a successor to the company's DC-8 for long-range operations, and competed in the same markets as theLockheed L-1011 Tristar, which has a similar layout to the DC-10.

Production of the DC-10 ended in 1989 with 386 delivered to airlines and 60 to the U.S. Air Force as air-to-air refueling tankers, designated the KC-10 Extender. The DC-10 was succeeded by the relatedMcDonnell Douglas MD-11 which entered service in 1990.

Following an unsuccessful proposal for the US Air Force's CX-HLS (Heavy Logistics System) in 1965, Douglas Aircraft began design studies based on its CX-HLS design. In 1966, American Airlines offered a specification to manufacturers for a widebody aircraft smaller than the Boeing 747 but capable of flying similar long-range routes from airports with shorter runways. The DC-10 became McDonnell Douglas's first commercial airliner after the merger between McDonnell Aircraft Corporation and Douglas Aircraft Company in 1967.

The DC-10 was first ordered by launch customers American Airlines with 25 orders, and United Airlines with 30 orders and 30 options in 1968. The DC-10, a series 10 model, made its first flight on August 29, 1970. Following a flight test program with 929 flights covering 1,551 hours, the DC-10 was awarded a type certificate from the FAA on July 29, 1971. It entered commercial service with American Airlines on August 5, 1971 on a round trip flight between Los Angeles and Chicago. United Airlines began DC-10 service on August 16, 1971. The DC-10's similarity to the L-1011 in terms of passenger capacity and launch in the same timeframe resulted in a head to head sales competition which affected profitability of the aircraft.

The first DC-10 version was the "domestic" series 10 with a range of 3,800 miles (3,300 nmi, 6,110 km) with a typical passenger load and a range of 2,710 miles (2,350 nmi, 4,360 km) with maximum payload. The series 15 had a typical load range of 4,350 miles (3,780 nmi, 7,000 km). The series 20 was powered by Pratt & Whitney JT9D engines, whereas the series 10 and 30 engines were General Electric CF6. Before delivery of its aircraft, Northwest's president asked that the "series 20" aircraft be redesignated "series 40" because the aircraft was much improved over the original design. The FAA issued the Series 40 certificate on October 27, 1972.

The series 30 and 40 were the longer range "international" versions. One of the main visible differences between the models is that the series 10 has three sets of landing gear (one front and two main) while the series 30 and 40 have four gear (one front, three main). The center main two-wheel landing gear (which extends from the center of the fuselage) was added to accommodate the extra weight by distributing the weight and providing additional braking. The series 30 had a typical load range of 6,220 mi (10,010 km) and a maximum payload range of 4,604 mi (7,410 km). The series 40 had a typical load range of 5,750 miles (9,265 km) and a maximum payload range of 4,030 miles (3,500 nmi, 6,490 km).

Eventually, the DC-10 was able to distinguish itself from its competitors with two engine options, as well as earlier introduction of longer range variants than the L-1011. The 446th and final DC-10 rolled off the production line in December 1988 and was delivered to Nigeria Airwaysin July 1989. The DC-10 was assembled at McDonnell Douglas's Douglas Products Division in Long Beach, California. As the final few DC-10 deliveries were occurring, McDonnell Douglas had already started production of the DC-10's successor, the MD-11.

The DC-10 is a low-wing cantilever monoplane with a conventional tail unit with a single fin and rudder. It is powered by two turbofan engines mounted on underwing pylons and a third engine at the base of the vertical stabilizer. It has a retractable tricycle landing gear. The later series 30 and 40 have an additional two-wheel main landing gear on the centerline of the fuselage. It was designed to be a medium to long-range airliner with a widebody fuselage to seat over 250 passengers. It is operated by a flight-crew of three located on the flightdeck in the nose on the same level as the passenger cabin. The fuselage has underfloor stowage for cargo and baggage.
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KC-135 Stratotanker

The Boeing KC-135 Stratotanker was the first jet powered aerial refueling tanker of the US Air Force, replacing the KC-97 Stratotanker. Similar in design to the later and enlarged Boeing 707 airliner, it was initially tasked to refuel strategic bombers, but was used extensively in the Vietnam war and later conflicts such as Desert Storm to extend the range and endurance of both Air Force and Navy tactical fighters and bombers.

Serving with the United States Air Force since 1957, it is one of just six military fixed wing aircraft with over 50 years of continuous service with the original service along with the Tupolev Tu-95, the C-130 Hercules, the B-52 Stratofortress, the English Electric Canberra and the Lockheed U-2. Supplemented by the larger KC-10, complete replacement is still under study by the Air Force. Despite increased maintenance costs, studies conclude many of the aircraft could be flown until 2040, with ages reaching 80 years before reaching lifetime flying hour limits.

The KC-135 is derived from the original Boeing jet transport "proof of concept" demonstrator, the Boeing 367-80 (commonly called the "Dash-80"). As such, it has a narrower fuselage and is shorter than the Boeing 707 jetliner. Boeing gave the tanker the designation of Model 717. The 367-80 was the basic design for the commercial Boeing 707 passenger aircraft as well as the KC-135A Stratotanker.

In 1954 the USAF's Strategic Air Command ordered the first 29 of its future fleet of 732. The first aircraft flew in August 1956 and the initial production Stratotanker was delivered to Castle Air Force Base, California, in June 1957. The last KC-135 was delivered to the Air Force in 1965.

Developed in the late 1950s, the basic airframe is characterized by swept wings and tail, four underwing mounted engine pods, a horizontal stabilizer mounted on the fuselage near the bottom of the vertical stabilizer with positivedihedral on the two horizontal planes and a hi-frequency radio antenna which protrudes forward from the top of the vertical fin or stabilizer. These basic features make it strongly resemble the commercial Boeing 707 and 720 aircraft, although it is actually a different aircraft.

The Strategic Air Command (SAC) had the KC-135 Stratotanker in service with Regular Air Force SAC units from 1957 through 1992 and with SAC-gained Air National Guard(ANG) and Air Force Reserve (AFRES) units from 1975 through 1992.

Following a major USAF reorganization that resulted in the inactivation of SAC in 1992, most KC-135s were re-assigned to the newly-created Air Mobility Command (AMC). While AMC gained the preponderance of the aerial refueling mission, a small number of KC-135s were also assigned to directly United States Air Forces in Europe(USAFE), Pacific Air Forces (PACAF) and the Air Education and Training Command (AETC). All Air Force Reserve Command (AFRC) KC-135s and most of the Air National Guard (ANG) KC-135 fleet became operationally-gained by AMC, while Alaska Air National Guard and Hawaii Air National Guard KC-135s became operationally-gained by PACAF.

Reconnaissance and command post variants of the aircraft, including the RC-135 Rivet Joint and EC-135 Looking Glass Post Attack Command & Control Systems were operated by SAC from 1963 through 1992, when they were re-assigned to the Air Combat Command (ACC). The USAF EC-135 Looking Glass was subsequently replaced in its role by the U.S. Navy E-6 Mercury aircraft, a new build airframe based on the Boeing 707 and KC-135.

The KC-135R has four turbofan engines, mounted under 35-degree swept wings, which power it to takeoffs at gross weights up to 322,500 pounds (146,300 kg). Nearly all internal fuel can be pumped through the tanker's flying boom, the KC-135's primary fuel transfer method. A special shuttlecock-shaped drogue, attached to and trailing behind the flying boom, may be used to refuel aircraft fitted with probes. A boom operator stationed in the rear of the aircraft controls the boom while lying prone. A cargo deck above the refueling system can hold a mixed load of passengers and cargo. Depending on fuel storage configuration, the KC-135 can carry up to 83,000 pounds (37,600 kg) of cargo.

Specifications (KC-135R)

General characteristics

  • Crew: 3: pilot, co-pilot and boom operator. Some KC-135 missions require the addition of a navigator.
  • Capacity: 37 passengers
  • Payload: 83,000 lb (37,600 kg)
  • Length: 136 ft 3 in (41.53 m)
  • Wingspan: 130 ft 10 in (39.88 m)
  • Height: 41 ft 8 in (12.70 m)
  • Wing area: 2,433 ft² (226 m²)
  • Empty weight: 98,466 lb (44,663 kg)
  • Loaded weight: 297,000 lb (135,000 kg)
  • Useful load: 200,000 lb (90,700 kg)
  • Max takeoff weight: 322,500 lb (146,000 kg)
  • Powerplant: 4× (R/T) CFM International CFM56 (F108-CF-100) turbofan, 21,634 lbf () each
  • Maximum Fuel Load: 31,275 US gal (118 kL)

Performance

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