Joint Strike Fighter program Joint Strike Fighter (JSF) is a development and acquisition program intended to replace a wide range of existing fighter, strike, and ground attack aircraft for the United States, the United Kingdom, Canada, Australia, The Netherlands and their allies. After a competition between the Boeing X-32 and the Lockheed Martin X-35, a final design was chosen based on the X-35. This is the F-35 Lightning II, which will replace various tactical aircraft, including the US F-16, A-10, F/A-18, AV-8B and British Harrier GR7 & GR9s, and the Canadian CF-18. Project formation The JSF program was the result of the merger of the Common Affordable Lightweight Fighter (CALF) and Joint Advanced Strike Technology (JAST) projects. The merged project continued under the JAST name until the engineering, manufacturing and development (EMD) phase, during which the project became the Joint Strike Fighter. JSF competition Outcome Program issues Alleged Chinese espionage
AN/SLQ-25 Nixie TB-14A towed decoy, from the AN/SLQ-25A "Nixie" system The AN/SLQ-25 Nixie and its variants are towed torpedo decoys used on US and allied warships. It consists of a towed decoy device (TB-14A) and a shipboard signal generator. The decoy emits signals to draw a torpedo away from its intended target. The Nixie attempts to defeat a torpedo's passive sonar by emitting simulated ship noise, such as propeller and engine noise, which is more attractive than the ship to the torpedo's sensors. The AN/SLQ-25A Nixie is a clean-sheet design when compared to the AN/SLQ-25 Nixie. The AN/SLQ-25B includes equipment of the AN/SLQ-25A and incorporates a towed array sensor to detect submarines and incoming torpedoes. The AN/SLQ-25C System is an upgrade to the AN/SLQ-25A system. Typically, larger ships may have two Nixie systems mounted on the rear of the ship to allow operation singularly or in pairs while smaller ships may have only one system.
Contra-rotating propellers Operation When airspeed is low, the mass of the air flowing through the propeller disk (thrust) causes a significant amount of tangential or rotational air flow to be created by the spinning blades. The energy of this tangential air flow is wasted in a single-propeller design. To use this wasted effort the placement of a second propeller behind the first takes advantage of the disturbed airflow. The tangential air flow also causes handling problems at low speed as the air strikes the vertical stabilizer, causing the aircraft to yaw left or right, depending of the direction of propeller rotation. If it is well designed, a contra-rotating propeller will have no rotational air flow, pushing a maximum amount of air uniformly through the propeller disk, resulting in high performance and low induced energy loss. Advantages and disadvantages Contra-rotating propellers have been found to be between 6% and 16% more efficient than normal propellers. Use in aircraft See also
British Aerospace Harrier II The British Aerospace Harrier II is a second-generation vertical/short takeoff and landing (V/STOL) jet aircraft used previously by the Royal Air Force (RAF) and, between 2006 and 2010, the Royal Navy (RN). The aircraft was derived from the McDonnell Douglas AV-8B Harrier II, which itself was a development of the Hawker Siddeley Harrier. Initial deliveries of the Harrier II were designated in service as Harrier GR5; subsequently upgraded airframes were redesignated accordingly as GR7 and GR9. Under the Joint Force Harrier organisation, both the RAF and RN operated the Harrier II, including routine operational deployments onboard the navy's Invincible class aircraft carriers. In December 2010, budgetary pressures led to the early retirement of all Harrier IIs from service, at which point it was the last of the Harrier derivatives remaining in British service. Design and development Origins Description and role RAF Harrier GR9 in flight, 2010 Further developments
Fridtjof Nansen-class frigate Design The frigates were originally intended as a replacement for the aging Oslo-class frigates, with a primary focus on antisubmarine warfare (ASW). Eventually, the need for a robust anti-aircraft defense as well as the possibility of incorporating the Naval Strike Missile SSM produced by Norwegian company Kongsberg Defence & Aerospace led to a more multi-role design. The selection of Navantia as prime contractor led to the design being very similar to the Spanish Navy's Alvaro de Bazan-class frigates, including the incorporation of Lockheed Martin's AEGIS combat system. Improvements The new frigates will prove a great improvement over their predecessors, the Oslo-class frigates, not only in size, but also in personnel, capabilities and equipment. Current activities In November 2009 she became involved in a firefight with suspected pirates after being attacked while inspecting a fishing vessel. Availability List of ships Images References
Hawker Siddeley P.1127 Improvements to future development aircraft, such as swept wings and more powerful Pegasus engines, led to the development of the Kestrel. The Kestrel was evaluated by the Tri-partite Evaluation Squadron, made up of military pilots from Britain, the United States, and West Germany. Later flights were conducted by the U.S. military and NASA. Related work on a supersonic aircraft, the Hawker Siddeley P.1154, was cancelled in 1965. As a result, the P.1127 (RAF), a variant more closely based on the Kestrel, was ordered into production that year, and named Harrier in 1967. Design and development Background P.1127 Third prototype P.1127 XP972 at Farnborough 1962, showing the unswept trailing edges The first prototype P.1127, serial XP831, was delivered in July 1960 for static engine testing, and in October the Pegasus flight engine was made available. The first three P.1127s crashed, the second and third during development. Kestrel FGA.1 P.1127 (RAF) Variants
Lockheed Martin F-35 Lightning II The Lockheed Martin F-35 Lightning II is a family of single-seat, single-engine, fifth-generation multirole fighters under development to perform ground attack, reconnaissance, and air defense missions with stealth capability. The F-35 has three main models; the F-35A is a conventional takeoff and landing variant, the F-35B is a short take-off and vertical-landing variant, and the F-35C is a carrier-based variant. The F-35 is descended from the X-35, the product of the Joint Strike Fighter (JSF) program. It is being designed and built by an aerospace industry team led by Lockheed Martin. F-35 JSF development is being principally funded by the United States with additional funding from partners. Development JSF program requirements and selection The JSF program was designed to replace the United States military F-16, A-10, F/A-18 (excluding newer E/F "Super Hornet" variants) and AV-8B tactical fighter aircraft. Design phase On 7 July 2006, the U.S.
Lockheed AC-130 The Lockheed AC-130 gunship is a heavily armed ground-attack aircraft variant of the C-130 Hercules transport plane. The basic airframe is manufactured by Lockheed, while Boeing is responsible for the conversion into a gunship and for aircraft support. The AC-130A Gunship II superseded the AC-47 Gunship I during the Vietnam War. All of the weaponry aboard is mounted to fire from the left (port) side of the non-pressurised aircraft. During an attack the gunship performs a pylon turn, flying in a large circle around the target, allowing it to fire at it far longer than a conventional attack aircraft. The AC-130H Spectre was armed with two 20 mm M61 Vulcan cannons, two Bofors 40mm autocannon, and one 105 mm M102 cannon, although on most missions after 1994 the 20 mm cannons were removed due to their incompatibility with precision targeting and to carry more 40 mm and 105 mm ammunition. Development Origins AC-130H Spectre near Hurlburt Field, Florida in 1988
Ryan XV-5 Vertifan The Ryan XV-5 Vertifan was a jet-powered V/STOL experimental aircraft in the 1960s. The U.S. Army commissioned the Ryan VZ-11RY (which was redesignated as the XV-5 in 1962) in 1961, along with the Lockheed VZ-10 Hummingbird (redesignated as the XV-4). Design XV-5A Models. The XV-5 drove three fans. A set of louvered vanes underneath each of the large wing fans could vector the thrust in any direction and provided yaw control. The project performance was moderately subsonic, with delta wings somewhat like an A-4 Skyhawk. The XV-5A was finished in Army green, while the XV-5B was painted in white NASA colors. The XV-5 was one of many dozens of aircraft which attempted to produce a successful vertical takeoff aircraft, but the lift fan system was heavy and occupied considerable internal volume. Operational history Two 12,500 lb (maximum gross weight) XV-5A were evaluated in late 1966 by fifteen test pilots (the "XV-5A Fan Club"). Specifications (XV-5) (performance estimated)
British Aerospace Sea Harrier The British Aerospace Sea Harrier is a naval short take-off and vertical-landing/vertical take-off and landing jet fighter, reconnaissance and attack aircraft, a development of the Hawker Siddeley Harrier. It first entered service with the Royal Navy in April 1980 as the Sea Harrier FRS1 and became informally known as the "Shar". Unusual in an era in which most naval and land-based air superiority fighters were large and supersonic, the principal role of the subsonic Sea Harrier was to provide air defence of the fleet from Royal Navy aircraft carriers. The Sea Harrier served in the Falklands War, both of the Gulf Wars, and the Balkans conflicts; on all occasions it mainly operated from aircraft carriers positioned within the conflict zone. Its usage in the Falklands War was its most high profile and important success, where it was the only fixed-wing fighter available to protect the British Task Force. Development Design Locations of the four nozzles on the aircraft. 
GAU-12 Equalizer The General Dynamics GAU-12/U Equalizer is a five-barrel 25 mm Gatling-type rotary cannon. The GAU-12/U is used by the United States, Italy and Spain, which mount the weapon in their fighter jets such as the AV-8B Harrier II, airborne gunships such as the Lockheed AC-130, and land-based fighting vehicles. Development The five-barrel 'Equalizer' cannon was developed in the late 1970s, based on the mechanism of the GAU-8/A Avenger cannon, but firing a new NATO series of 25 mm ammunition. The GAU-12/U cannon is operated by a 15 hp (11 kW) electric motor, in external mounts supplied by a bleed air driven pneumatic system. Uses An AV-8 Harrier II; the two pods on the underside of the fuselage hold the cannon (left-hand side of the aircraft, visible hole) and ammunition (right-hand side of the aircraft). RAF and Fleet Air Arm Harriers have not adopted the Equalizer for their Harrier GR7 and GR9s. The Equalizer was also used as the basis for the Sea Vulcan 25. GAU-22/A
STOVL See also: V/STOL A short take-off and vertical landing aircraft (STOVL aircraft) is a fixed-wing aircraft that is able to take off from a short runway (or take off vertically if it does not have a heavy payload) and land vertically (i.e. with no runway). The formal NATO definition (since 1991) is: A Short Take-Off and Vertical Landing aircraft is a fixed-wing aircraft capable of clearing a 15 m (50 ft) obstacle within 450 m (1,500 ft) of commencing take-off run, and capable of landing vertically. On aircraft carriers, non-catapult-assisted, fixed-wing short takeoffs are accomplished with the use of thrust vectoring, which may also be used in conjunction with a runway "ski-jump". History Comparison of lift and thrust for various aircraft In 1951, the Lockheed XFV-1 and the Convair XFY tailsitters were both designed around the Allison YT40 turboprop engine driving contra-rotating propellers. In 1962, Lockheed built the XV-4 Hummingbird for the U.S. References