A tiltrotor is an aircraft which generates lift and propulsion by way of one or more powered rotors mounted on rotating engine pods or nacelles usually at the ends of a fixed wing or an engine mounted in the fuselage with drive shafts transferring power to rotor assemblies mounted on the wingtips. It combines the vertical lift capability of a helicopter with the speed and range of a conventional fixed-wing aircraft. For vertical flight, the rotors are angled so the plane of rotation is horizontal, lifting the way a helicopter rotor does. As the aircraft gains speed, the rotors are progressively tilted forward, with the plane of rotation eventually becoming vertical. In this mode the wing provides the lift, and the rotor provides thrust as a propeller. Since the rotors can be configured to be more efficient for propulsion and it avoids a helicopter's issues of retreating blade stall, the tiltrotor can achieve higher speeds than helicopters.
The Sikorsky CH-53E Super Stallion is a heavy-lift helicopter operated by the United States military. As the Sikorsky S-80 it was developed from the CH-53 Sea Stallion, mainly by adding a third engine, adding a seventh blade to the main rotor and canting the tail rotor 20 degrees. It was built by Sikorsky Aircraft for the United States Marine Corps. The less common MH-53E Sea Dragon fills the United States Navy's need for long range minesweeping or Airborne Mine Countermeasures (AMCM) missions, and perform heavy-lift duties for the Navy. Under development is the Sikorsky CH-53K King Stallion, which has new engines, new composite material rotor blades, and a wider aircraft cabin; this is to replace the CH-53E.
The Sikorsky MH-53 Pave Low series is a long-range combat search and rescue (CSAR) helicopter for the United States Air Force. The series was upgraded from the HH-53B/C, variants of the Sikorsky CH-53 Sea Stallion. The HH-53 "Super Jolly Green Giant" was initially developed to replace the HH-3E "Jolly Green Giant". The helicopters later transitioned to Special Operations missions. The U.S. Air Force's MH-53J/M fleet was retired in September 2008.
London Heliport, previously called Battersea Heliport and currently known officially as the NetJets London Heliport for sponsorship reasons, is London's only licensed heliport. The facility, which was built by W. & C. French and opened on 23 April 1959, is located in Battersea on the south bank of the River Thames, 3 NM southwest of Westminster Bridge and between Wandsworth Bridge and Battersea Railway Bridge.
Tandem rotor helicopters have two large horizontal rotor assemblies mounted one in front of the other. Currently this configuration is mainly used for large cargo helicopters.
USS Jesse L. Brown (DE/FF/FFT-1089) was a Knox-class frigate of the United States Navy. She was named for Jesse L. Brown, the first African-American naval aviator in the U.S. Navy. The ship was eventually decommissioned and sold to the Egyptian Navy and was renamed Damiyat (F961). The name is also transliterated as Damyat and Damietta by some sources.
The tail rotor is a smaller rotor mounted so that it rotates vertically or near-vertically at the end of the tail of a traditional single-rotor helicopter. The tail rotor's position and distance from the center of gravity allow it to develop thrust in the same direction as the main rotor's rotation, to counter the torque effect created by the main rotor. Tail rotors are simpler than main rotors since they require only collective changes in pitch to vary thrust. The pitch of the tail rotor blades is adjustable by the pilot via the anti-torque pedals, which also provide directional control by allowing the pilot to rotate the helicopter around its vertical axis.
Coaxial rotors or "coax rotors" are a pair of helicopter rotors mounted one above the other on concentric shafts, with the same axis of rotation, but turning in opposite directions (contra-rotating). This configuration is a feature of helicopters produced by the Russian Kamov helicopter design bureau.
A helicopter main rotor or rotor system is the combination of several rotary wings and a control system that generates the aerodynamic lift force that supports the weight of the helicopter, and the thrust that counteracts aerodynamic drag in forward flight. Each main rotor is mounted on a vertical mast over the top of the helicopter, as opposed to a helicopter tail rotor, which connects through a combination of drive shaft(s) and gearboxes along the tail boom. The blade pitch is typically controlled by a swashplate connected to the helicopter flight controls. Helicopters are one example of rotary-wing aircraft (rotorcraft). The name is derived from the Greek words helix, helik-, meaning spiral; and pteron meaning wing.
A backpack helicopter is a helicopter motor and rotor and controls assembly that can be strapped to a person's back, so he can walk about on the ground wearing it, and can use it to fly. It uses a harness like a parachute harness and should have a strap between the legs. Some designs may use a ducted fan design to increase upward thrust. Several inventors have tried to make backpack helicopters, with mixed results.
Improved rotor efficiency resulting from directional flight in a helicopter is called translational lift. The efficiency of the hovering rotor system is greatly improved with each knot of incoming wind gained by horizontal movement of the aircraft or surface wind. As the incoming wind produced by aircraft movement or surface wind enters the rotor system, turbulence and vortices experienced in hovering flight are left behind and the flow of air becomes more horizontal. While transitioning to forward flight at about 16 to 24 knots, the helicopter goes through effective translational lift (ETL). As mentioned earlier in the discussion on translational lift, the rotor blades become more efficient as forward airspeed increases. Between 16 and 24 knots, the rotor system completely outruns the recirculation of old vortices and begins to work in relatively undisturbed air.
A rotorcraft or rotary-wing aircraft is a heavier-than-air flying machine that uses lift generated by wings, called rotary wings or rotor blades, that revolve around a mast. Several rotor blades mounted on a single mast are referred to as a rotor. The International Civil Aviation Organization (ICAO) defines a rotorcraft as "supported in flight by the reactions of the air on one or more rotors". Rotorcraft generally include those aircraft where one or more rotors are required to provide lift throughout the entire flight, such as helicopters, autogyros, and gyrodynes. Compound rotorcraft may also include additional thrust engines or propellers and static lifting surfaces.
Helicam is a remote-controlled mini helicopter used to obtain aerial pictures or motion images using video, still or motion film cameras. The remote controlled camera mount system allows pan, tilt and roll movements. A wireless onboard video transmitter downlinks the live signal to the camera operator, images can be recorded on board, on the ground or both. The system is controlled by two operators with independent controls: the helicam pilot and camera operator.
A military helicopter is a helicopter that is either specifically built or converted for use by military forces. A military helicopter's mission is a function of its design or conversion. The most common use of military helicopters is transport of troops, but transport helicopters can be modified or converted to perform other missions such as combat search and rescue (CSAR), medical evacuation (MEDEVAC), airborne command post, or even armed with weapons for attacking ground targets. Specialized military helicopters are intended to conduct specific missions. Examples of specialized military helicopters are attack helicopters, observation helicopters and anti-submarine warfare helicopters.
Autorotation is a state of flight in which the main rotor system of a helicopter or similar aircraft turns by the action of air moving up through the rotor, as with an autogyro, rather than engine power driving the rotor. The term autorotation dates to a period of early helicopter development between 1915 and 1920, and refers to the rotors turning without the engine. It is analogous to the gliding flight of a fixed-wing aircraft.
The Knud Rasmussen class is a class of offshore patrol vessels operating in the Royal Danish Navy from 2008. Built to replace the Agdlek-class cutters on a one-by-one basis, the Knud Rasmussen-class vessels are significantly larger, enabling patrols further offshore.
A multirotor or multicopter is a rotorcraft with more than two rotors. An advantage of multirotor aircraft is the simpler rotor mechanics required for flight control. Unlike single- and double-rotor helicopters which use complex variable pitch rotors whose pitch varies as the blade rotates for flight stability and control, multirotors often use fixed-pitch blades; control of vehicle motion is achieved by varying the relative speed of each rotor to change the thrust and torque produced by each.
The Tactical Supply Wing (TSW), a/k/a "Tiswas" was formed at RAF Stafford in late 1970 and became operational in January 1971. Tiswas was sent on its first operational deployment to Northern Ireland in 1971. Elements of TSW have deployed around the world to support British and NATO helicopter units in most major exercises and conflicts since it was formed.
