Wednesday, March 30, 2011
The History Of Helicopter Discovery
The helicopter is an aircraft that picked up and driven by one or more rotors (propeller) large horizontal. Helicopters are classified as-rotating wing aircraft to distinguish them from ordinary fixed-wing aircraft other. The word comes from the Greek helicopter helix (spiral) and pteron (wing). The helicopter operated by the machine invented by the inventor of Slovakia in January Bahyl.
Compared with other fixed-wing aircraft, helicopters are more complex and more expensive to buy and operate, rather slow, has a close distance and roaming charges are limited. While the advantage is its movement; helicopters capable of flying in space, backward, and take off and land vertically. Limited in the addition of fuel facilities and load / altitude, the helicopter can fly to any location, and land anywhere with a pitch of the rotor and a half in diameter. Called a helipad helipad.
The working principle Helicopters
Helicopters can fly because of lift generated by air flow generated by the blades of the propeller rotor. Propeller was a stream of air flow from top to bottom. Air flow in such a swift so that they can lift objects weighing dozens of tons. His theory is actually quite simple but practically complex.
In essence, the basic principles of flying fixed wing aircraft (fixed wing) with a helicopter which is also known rotary winged aircraft is essentially fixed. The key was on the two major forces that work integrated, produce lift and thrust are great.
On the strength of the first fixed wing aircraft produced by the air flow at the surface of the wings that form a certain angle with small wings that flap in the rear wing of the position upheld. So that the air flow flowing backwards could be directed back to the top. The air flowing at the bottom of the wing surface pressure is relatively flat surface of the wing was involved pressing upward causing the lift and cause the plane upward. At least 15 percent of the total force generated, used to lift the fuselage upward.
Another major strength is the thrust produced by the flow of air in the upper wing surface is relatively curved shape. When the air flow generated by the engine flows into the rear and through the main wing, the airflow is divided. Air stream flowing over the wing upper surface is more rapid than the flow of air that hit the bottom of the wing surface. But the pressure of air flowing over the wing upper surface, relatively small compared with the air pressure in the lower wing surface is precisely the flow is less heavy. This air pressure difference causes the wing upward. To imagine how much lift it, the theory states that the air pressure difference of 2.5 ounces per square inch to produce lift 20 pounds per square foot (1 foot = 20 cm). Can be calculated, if the wing area 1000 square feet, the lift force generated will reach 10 tons.
In the helicopter, the function of the wing was replaced by propeller blades though each smaller than a regular airplane wing, but when played, curvanya relatively similar to the wing. To get the lift, the rotor blades must be directed at a particular position so as to form a large angle. The principle is the same as fixed wing aircraft, the helicopter there are two major forces that influence each other. Air flow moving forward propeller blades so that the pressing blade propeller driven back to back results in a small lift. But when when the flow of air moving quickly over the top and bottom of the blades of the propeller, a large air pressure between the blades will automatically expand to the entire surface of the lower pressure, causing the propeller driven up and the helicopter were drawn. Remember, even though the blades of the propeller is just a few pieces, but in a state of racing, he will form a flat surface and the air is pressed onto the large pressure menimbukan which eventually resulted in a greater lift. This principle is equivalent to the propellers on the aircraft-engine turboprop and the same with "propeller" children's toys.
Some of the helicopters used in warfare, such as Mi-26 Hind for example equipped with small wings called the Canard, the first function to relieve the burden on the main rotor and the second to increase the rate and extend the reach cruising speed. Another function is as a hanger weapons, missiles and others. By adding this short wings, the functional differences between fixed plane with a helicopter to be vague. Fixed wing aircraft is also capable of flying-landing vertically (Vertical Take-off Landing / VTOL). Contonya, of a kind Sea Harrier AV-8 Harrier or Harrier.
Excess fixed wing aircraft, especially about the flight because the plane of this type have a wide platform that is relatively more stable during flight. Questions flew it, it matters set aileron on the wing and vertical stabilizer and the existing flat on the tail. But the helicopter is not the case. When the blades of the propeller rotornya rotornya own produce lift themselves working on it move the air down as much. While the weight of the displaced air thus reducing the heavy helicopter helicopter lifted. And if the helicopter was lifted, means there is a balance between the weight of air displaced from the top down with the weight of helicopter. To operate the helicopter was there the usual steering tool disebutcollective pitch and cyclic pitch of each function as a regulator and booster lift helicopters for moving forward. So simple how it works, but transforming in a technology job really very complicated.
Similarly, the rotor configuration, not just to rotate and fly and float. Because the propeller rotated setap will always cause torque generally termed torque. To eliminate or counteract the power play that could cause the helicopter body is spinning, it needs to be installed antitorque.
This can be Antitorque tail rotor or tail rotor mounted on the tail of the aircraft that also serves as a rudder. This configuration can be seen in the general helicopter like the Bell-412, Bell-205 or UH-1 Huey, or NBO-105, and AS-330 Puma or Super Puma AS-335, AH-64 Apache or the Mi-24 Hind. Selin using the tail rotor, there are still some other Desai. For example, using a tandem system as used on helicopter Boeing CH-47 Chinook or CH-46 Sea Knight. Both the rotor, which together are large each placed in front of and behind the helicopter body. Both symmetrical but has a round in the opposite direction. That is to negate each other round effects arising from each other, intermesh in popular language. Another way is to configure egg-beater. This design configuration as used on helicopter Kamov Ka-25 Russian-made or Kaman HH-43 Husky. Both the blades of the same magnitude was placed in one axis, separated from each other where a single rotor mounted above the other. Both are rotating in opposite directions. That is to eliminate the effects of rotation or torque.
Other Ways Than the three above, Also made the configuration without a tail rotor. This helicopter is called NOTAR (No Tail Rotor) system has a Slightly different with the existing system of Nowhere the use of a blast of hot gas from the main engine is channeled through the tail tube. Examples are MD-902 Explorer helicopter
On or Tilt Rotor Rotor and Wing On or Tilt Wing
Takeoff and landing style characterized by helicopter but fly fixed wing aircraft types is a concept embraced by helicopter of this type. The easiest way is to incorporate the concept of working helicopters with fixed wing aircraft in a single form.
The principle works technically, when the main rotor is directed upward by the vertical movement can be done while helikoter when the rotor is directed forward or backward (as pursher or driving) then the characters fly like a plane can still be obtained. Rotor motion such as this do not need to involve the wings.
Actually the development of active rotor is still covered with uncertainty, the problem is the system that you want can be called a fixed wing aircraft because it has a large berlumayan wings, tail plane and also have a fixed wing aircraft configured with ordinary. Finally, this concept called the hybrid concept. Examples of this helicopter is the V-22 Osprey. In addition to the active rotor concepts, there is also an active wing concept, which is driven rotor as the rotor is not active but the wing plane. While the engine remained in his position. Examples of this helicopter is the TW-68 is designed by Ishida Corporation, Japan, this design was mentioned refer to as having a more compact design compared to the active rotor sustainability unfortunately just is not so sound.
Helicopter Jump Seats
Actually, the helicopter trip into a form that is known at the time this takes quite a long period of time. In the process, also involves the development of technology and also the inventor and developer helikoter.
The first helicopter flew the man is the Breguet-Richet helicopter, 1907. Heli is flying in Douai, France on September 29, 1907. Helicopters are still getting help from four people who hold all four feet. This effort did not get a good record as the first helicopter to fly free. However, this proves the success of the helicopter vertical flight theory that time was still considered a theory. This is the first machine that can fly by itself carry a pilot vertically as a result of wing lift swivel. Heli uses powerful 50 hp Antoinette engine.
Flying helicopters actually done by Paul Cutaneous using a twin-engine helicopters Antoinette 24 hp at Lisieux, France on November 13, 1907. The flight lasted 20 seconds to a height of 0.3 meter. While the first Gyroplane Helicopter type C4 achieved by artificial Autogiro Juan de la Cierva. Autogiro first flew on January 9, 1923. The secret of success in the adoption of a joint system of flapping hinges the blades to the rotor head. While the helicopter which first flew successfully carried out by type of Fock Wulf FW-61 double berotor designed by Professor Heinrich Focke in the year 1933-1934. The helicopter was doing flying debut on June 26, 1936 and powered by Siemens-Halske Sh 14A-powered 160 hp. Heli was flown by Ewald Rohlfs. Heli fly as far as this record 122.35 km and long flown one hour 20 minutes 49 seconds. At other times he flew to a height of 3427 meters and record the speed of 122 miles / hour.
Helicopter pioneer developer of technology
Leonardo da Vinci (1452-1519)
Leonardo da Vinci actually developed the concept of vertical flight and was previously a children's toy from the plains of China, it is unclear exactly since when children's toys was developed there and who inisiatornya or discoverer. In 1483 Leonardo da Vinci developed the concept of the screw flight.
Sir George Cayley (1773-1857)
Sir George Cayley is known as an engineer and innovator in air navigation and aerodynamics. One of the introduction of the term angle of attack in the world of aviation. In history, he is a figure who develop fixed-wing aircraft and gliders or gliders however, he developed the rotary wing or helicopter. Helicopters are the introduction of a compilation of wood, fur, cork and wire.
In 1842, Cayley designed the helicopter better, especially when they know that spin the propeller can lead to disastrous and require antidotes. Deterrence theory is also presented by him. To be able to fly, this helikpter put two rotors which move in opposite directions. Although the design is not yet tangible helicopter with an airborne helicopter, the concept used by the Kamov helicopters from Russia and Focke of Germany.
Nikolai Egorovich Zhikovsky (1847-1921)
Zhukovsky aviation career began with pursue mathematics, hydrodynamics and aerodynamics. Zhukovsky then discovered the world's first wind tunnel to test the aerodynamic technology. Falls in the development of a helicopter in 1910 and in World War I developed a lot of airplanes and helicopters
Juan de la Cierva (1895-1936)
Cierva developed a helicopter after a homemade double-winged bomber fell in 1919, the reason is the stability of the helicopter sees higher. In developing the design helicopter, Cierva ignore the various theories developed previously, using the newly-made designs which are based on the theory he developed through various experiments. Autogiro which is resulting in a hodgepodge concept aircraft between aircraft flying generally so that it can perform a vertical landing, half helicopter and half airplane. Autogiro Cierva flew in 1923. Five years later Cierva do Autogiro flights around Europe with more than 5000 km as far as he promoted. His efforts were not in vain because Autogiro a number of industrial design is great demand in Europe. Autogiro Cierva died in an accident in Croydon in 1936.
Igor Ivanovich Sikorsky (1889-1972)
Sikorsky took an interest in flight by designing various aircraft models including a helicopter from an early age. At first he entered the Naval Academy in St. Petersburg who later resigned and went to Paris to explore the science of engineering and aviation. After Paris, he returned to Kiev, Ukraine and develop the helicopter but failed. Sikorsky Bolshevik Revolution forced to move to Paris and then settled in the United States.
In 1939 he flew his first helicopter VS-300 and during its development, has recorded several record helicopter flight. Until entering the 21st century there are about 40,000 man-made Sikorsky helicopters flying in various parts of the world.
Mikhail Mill (1909-1970)
As with Sikorsy, Mill took an interest in aviation early age. He won the competition model airplanes at age 12. He then entered the Aviation Institute in Novocherkassk and develop the first autogiro with supervision and guidance of Kamov and Skrzhinsky. After graduating in 1931, he entered the center of the Russian aerodynamics TsAGi, and it was here doing research on helicopter aerodynamics with an emphasis on stability and design of the rotor.
In 1947, Miles was appointed head of design of new helicopters and helicopters bring GM-1 is known to be a Mi-1 Hare. Success Hare guide further development of the most famous helicopters like Mi-4, Mil Mi-6 Hook Mi-8 and others.