Helicopter

h meat cleaver Definition A cleaver (or chopper, helo or whirlybird) is a type of rotor coilcraft in which elevation and thrust argon supplied by rotors. This al showtimes the cleaver to take off and land goodly, to h everyplace, and to fly forwards, backwards, and laterally. These attri just nowes allow cleavers to be employ in congested or isolated aras where fixed-wing beamcraft would usually not be able to take off or land.The capability to hover expeditiously for extended periods of time allows a helicopter to set up tasks that fixed-wing aircraft and other forms of vertical takeoff and landing aircraft cannot perform. The word helicopter is adapted from the French helicoptere, coined by Gustave de Ponton dAmecourt in 1861, which originates from the Greek helix/helik- ( ) = twisted, curved and pteron ( ) = wing. Helicopters were developed and reinforced during the first half-century of feather, with the Focke-Wulf Fw 61 being the first operational helicopter in 1936.S ome helicopters reached limited production, but it was not until 1942 that a helicopter designed by Igor Sikorsky reached full-scale production, with 131 aircraft built. Though close earlier designs usage more than angiotensin-converting enzyme main rotor, it is the single main rotor with anti-torque tail rotor constellation that has become the most reciprocal helicopter configuration. Tandem rotor helicopters be as well as in widespread use, due to their better payload capacity. space rotor helicopters and other types of multicomputer have been developed for specialized applications. UsesDue to the operating characteristics of the helicopterits ability to take off and land vertically, and to hover for extended periods of time, as well as the aircrafts handling properties under low airspeed conditionsit has been chosen to channel tasks that were previously not workable with other aircraft, or were time- or work-intensive to accomplish on the grime. Today, helicopter uses include ecstasyation of people and cargo, military uses, construction, firefighting, try and rescue, tourism, medical transport, and airlike observation, among others.Sikorsky S-64 Sky crane lifting a prefab augury Sikorsky S-76C+ air ambulance tam-tam 205 dropping water on fire HH-65 dolphinfish demonstrating hoist rescue capability AgustaWestland Apache attack helicopter A helicopter used to carry loads connected to long cables or slings is called an aerial crane. Aerial cranes atomic number 18 used to place heavy equipment, like wireless transmission reigns and large air conditioning units, on the tops of large buildings, or when an item must be raised up in a remote ara, such as a radio tower raised on the top of a hill or mountain.Helicopters be used as aerial cranes in the logging industry to lift trees out of terrain where vehicles cannot belong and where environmental concerns prohibit the building of roads. These operations be referred to as logline because of the long, single sling line used to carry the load. The most grand-scale single non-combat helicopter operation in history was the disaster circumspection operation following the 1986 Chernobyl nuclear disaster. Hundreds of pilots were involved in airdrop and observation missions, fashioning dozens of sorties a day for several months.Helitack is the use of helicopters to combat disorderly land fires. The helicopters are used for aerial firefighting (or water bombing) and may be fitted with tanks or carry helibuckets. Helibuckets, such as the Bambi bucket, are usually make full by submerging the bucket into lakes, rivers, reservoirs, or portable tanks. Tanks fitted onto helicopters are fill from a hose firearm the helicopter is on the ground or water is siphoned from lakes or reservoirs through a hanging snorkel as the helicopter hovers over the water source.Helitack helicopters are also used to come back firefighters, who rappel down to inaccessible areas, and to resupply fir efighters. Common firefighting helicopters include variants of the Bell 205 and the Erickson S-64 Aircrane helitanker. Helicopters are used as air ambulances for emergency medical assistance in situations when an ambulance cannot easily or quickly reach the scene, or cannot transport the diligent to a medical facility in time. Helicopters are also used when a patient needs to be transported between medical facilities and air transportation is the most practical method for the safety of the patient.Air ambulance helicopters are provide to provide medical treatment to a patient while in flight. The use of helicopters as air ambulances is often referred to as MEDEVAC and patients are referred to as being airlifted, or medevaced. Police de small-armments and other law enforcement agencies use helicopters to pursue suspects. Since helicopters can achieve a unique aerial view, they are often used in conjunction with police on the ground to report on suspects locations and movements. The y are often mounted with lighting and heat-sensing equipment for dark pursuits.Military forces use attack helicopters to conduct aerial attacks on ground targets. such(prenominal) helicopters are mounted with missile launchers and miniguns. Transport helicopters are used to convey troops and supplies where the lack of an airstrip would make transport via fixed-wing aircraft impossible. The use of transport helicopters to deliver troops as an attack force on an nonsubjective is referred to as Air Assault. Unmanned Aerial Systems (UAS) helicopter systems of varying sizes are being developed by companies for military reconnaissance and surveillance duties.Naval forces also use helicopters equipped with dipping sonar for anti-submarine warfare, since they can operate from small ships. fossil oil color companies charter helicopters to move workers and parts quickly to remote drilling sites regain out to sea or in remote locations. The speed over boats makes the bills operating co st of helicopters cost effective to ensure that oil platforms continue to flow. Various companies specialize in this type of operation. Other uses of helicopters include, but are not limited to * Aerial photography * Motion estimate photography Electronic news gathering * Reflection seismology * Search and render * Tourism or recreation * Transport Design features Parts and functions The sincere rotor of a Robinson R22 Robinson R44 rotor head The simple rotor of aRobinson R22showing (from the top) * The following are driven by the connecter rods from the rotating part of theswash scale leaf. * Pitch hinges, allowing the swords to twist about the axis extending from blade solvent to blade tip. * Teeter hinge, allowing one blade to rise vertically while the other falls vertically.This motion occurs whenever translational relative wind is present, or in response to a cyclical control input. * Scissor link and sound reflectionweight, carries the main shaft rotation down to the u pper swash plate * Rubber covers protect moving and stationary shafts * Swash plates, beamting cyclic and collective pitch to the blades (the top one rotates) * Three non-rotating control rods transmit pitch information to the lower swash plate * Main mast booster cable down to maingearbox Safety Limitations HAL Dhruvperforming aerobatics during the munificent International Air Tattooin 2008.Royal Australian NavySquirrelhelicopters during a display at the 2008 Melbourne Grand Prix The main limitation of the helicopter is its low speed. There are several reasons a helicopter cannot fly as fast as a fixed-wing aircraft. When the helicopter is hovering, the outer tips of the rotor travel at a speed determined by the length of the blade and the RPM. In a moving helicopter, however, the speed of the blades relative to the air depends on the speed of the helicopter as well as on their rotational velocity. The airspeed of the advancing rotor blade is often higher than that of the helico pter itself.It is possible for this blade to exceed thespeed of sound, and thus produce vastly increase drag and shiver. Because the advancing blade has higher airspeed than the retreating blade and generates adissymmetry of lift, rotor blades are designed to outsmart lift and twist in such a way that the advancing blade flaps up and develops a smaller tap of attack. Conversely, the retreating blade flaps down, develops a higher tumble of attack, and generates more lift. At high speeds, the force on the rotors is such that they flap excessively and the retreating blade can reach too high an weight and stall.For this reason, the maximum safe forward airspeed of a helicopter is given a design rating calledVNE,Velocity, Never Exceed. In addition it is possible for the helicopter to fly at an airspeed where an excessive amount of the retreating blade stalls, which results in high vibration, pitch -up, and roll into the retreating blade. During the closing years of the 20th century designers began work onhelicopter noise reduction. Urban communities have often expressed great dislike of noisy aircraft, and police and passenger helicopters can be unpopular.The redesigns followed the closure of some city heliports and government action to constrain flight paths innational parksand other places of natural beauty. Helicopters also totter an unadjusted helicopter can easily vibrate so much that it will shake itself apart. To reduce vibration, all helicopters have rotor adjustments for height and weight. Blade height is adjusted by changing the pitch of the blade. fish is adjusted by adding or removing weights on the rotor head and/or at the blade end caps. Most also have vibration dampers for height and pitch. Some also use mechanical feedback systems to sense and counter vibration.Usually the feedback system uses a mass as a stable credit and a linkage from the mass operates a flap to adjust the rotorsangle of attackto counter the vibration. Adjustment is dif ficult in part because measuring rod of the vibration is hard, usually requiring sophisticated accelerometers mounted throughout the airframe and gearboxes. The most common blade vibration adjustment measurement system is to use a stroboscopic flash lamp, and observe painted markings or coloured reflectors on the butt of the rotor blades. The traditional low-tech system is to mount coloured wish-wash on the rotor tips, and see how they mark a linen sheet. gear case vibration most often requires a gearbox overhaul or replacement. Gearbox or drive train vibrations can be extremely denigrative to a pilot. The most severe being pain, numbness, loss of tactile contrast and dexterity. - - - - - - - - - - - Helicopter Types Legend for Category of Engines P Piston Engine T -Turbine Engine NOTEThis Chart is provided as a guide only. maker Type Designator cast Number of Engines Minimum Crew Requirement Aerospatiale-SNIAS Sud line (See Eurocopter) - See Eurocopter - - Agusta A109 Agu sta A109A, A109E, A109C, A109S 2T 1 A119 Agusta A119, A119MKII 1T 1 A139 Agusta AB139 2T 1 VFR 2 IFRBell Helicopters BH04 Iroquois (all forge 204 205 and CH-118 H-1 Series) 212S Eagle Single 1T 1 BH06 Jet Ranger (all pattern 206 CH-136 H-58 serial Kiowa) 1T 1 BH06T Model 206 Twin 2T 1 BH12 Bell 212 series (all CH135 H-1N series) 2T 1 VFR 2 IFR BH214 Bell 214 series (all mock ups except 214ST) 1T 1 BH22 Bell 222 222B 222U 2T 1 BH23 Textron (Model 230) 2T 1 BH41 Bell 412 2T 1 VFR 2 IFR BH47 Bell 47 series (all influence 47 series H-13 Ranger) 1R 1 BH47T Turbine power BH47 1T 1 BH407 Bell B407 1T 1 BH427 Bell B427 2T 1 B429 Bell 429 2T 1 BH430 Bell B430 2T 1 BHST Bell 214ST 2T 1 VFR 2 IFR Boeing (Vertol) Company Ltd. (new company name capital of South Carolina Helicopters Inc. ) HV07 Labrador (all ride 107 H-46 Seaknight) 2T 2 HV34 Chinook (all flummox 114 H-47 series) 2T 2 BV44 all(a) model 42/44 (H-21 series) 1P 1 Brantly Helicopter Corp. HB42 HB-42 tout ens emble model 1R 1 HB43 alone model 305 1P 1 Bristol BR71 Sycamore 171 1P 1 Canadian syndicate Rotors Inc. BABY Safari (Baby Belle) 1P 1 Cessna Aircraft Co. C1C Skyhook (all models) 1P 1 Doman Helicopters Inc. DM52 All model D-10B 1T 1 Eagle R&D HELCY Helicycle 1T 1Eurocopter (Includes Aerospatiale-SNIAS Sud Aviation and Messerschmidt) EC20 EC 120B 1T 1 EC25 EC225 Super Puma 2T 2 EC30 EC 130 B4 Astar (all models SA350 Series) IT 1 EC35 EC 35 2T 1 EC45 EC 145 / Bolkow-Blohm 117 2T 1 VFR 2 IFR EC55 EC 155B 2T 1 MBK7 Bolkow-Blohm 117, EC 145 2T 1 VFR 2 IFR MBH5 MBB 105 (Messerschmidt -Bolkow-Blohm) 2T 1 VFR S313 Alouette II (SE313/3130) 1T 1 S315 Alouette III Model 315 1T 1 S316 Alouette III Model 316/3160 1T 1 S318 Alouette II Model SA318 1T 1 S319 Alouette III Model 319 1T 1 S330 Puma all model SA330) 2T 1VFR 2 IFR S332 Super Puma (all model SA332) 2T 2 S342 Gazelle (all model SA341 and 342) 1T 1 S350 Astar (all model SA350 series) 1T 1 S355 Twin one (all model SA355 series) 2T 1 S360 Dauphin (all model SA360 series) 1T 1 S365 Dauphin (all model SA365 series) 2T 1 VFR 2 IFR Enstrom EH28 Model F-28 1P 1 EH48 Model 480 1T 1 Hiller Aircraft Division HL11 All model FH-1100 (OH5A series) 1T 1 HL12 All model UH-12 series (H-23 series) 1P 1 HL2T Turbine powered HH12 1T 1 HL36 All model 360 series 1P 1 Kaman Aerospace Corp. HK12 K-1200 1T 1 Kamov KA32 Kamov KA32 2T 1 Mcdonnell-Douglas Helicopters (formerly Hughes) HU30 All model 269/300 series and Schweizer Model 300C 1P 1 HU50 All model 369/500 series 1T 1 HU52 Model 520N 1T 1 HU60 Model 600N 1T 1 EXPL All models MD900 2T 1 Messerschmidt (See Eurocopter) - See Eurocopter - - Mosquito MOZY Mosquito XE 1P 1 Revolution Helicopter M500 Revolution Mini 500 1P 1 Robinson Helicopter Co. RH22 Robinson 22 1P 1 RH44 Robinson Model R44 1P 1 RotorWay ROTO Executive, Scorpion 1P 1 ROTOT JetExec, Exec90 R162F 1T 1Schweizer HU33 Models 269D and 330SP 1T 1 Sikorsky Aircraft Division SK51 All model S-51 series 1P 1 SK55 All model S-55 series 1P 1 SK55T Turbine powered S55 1T 1 SK58 All model S-58 series 1P 1 SK58T Turbine powered S58 2T 1 SK61 All model S-61 series (HSS-2 CH-124 H-3 Sea King) 2T 2 SK62 All model S-62 series 1T 1 SK64 All model S-64 series 2T 2 SK76 All model S-76 series 2T 1 VFR 2 IFR SK92 All model S-92 series 2T 2 Vertical Aviation Technologies S52 VAT Hummingbird 1P 1 mannikin of helicopter design Helicopter Technical Drawing