Monthly Archives: August 2011

MD500MD “tao”, “defenders

MD500MD “tao”, “defender remains the MD500 first head, the nose with M65” tao “, aim to provide. Equipped with four other “tao” type anti-tank missile clearing. Machines for striker has aimed at control device and armrest, and with the driver manipulation of the indicator. Can install, allison company 250-250-C20R C20 or 250-C30 engine. Israel’s air force buy 30 frame, Kenya to buy 15 frame, South Korea buy 50 frame. MD500MD/MMS “tao”, anti-tank type in MD on the basis of type, with the rotor mast aiming to provide.The MD500MD anti-submarine Defender is the anti-submarine and search variation. The two-man helicopter has a search radar on the nose, AN/ASQ-81 towed Magnetic Anomaly Detection system (MAD)on the side. And other equipments are smoke launcher, winch system, emergency floating system, two Mk44/Mk46 torpedo. Special instruments include 15.24mm pose displayer & radar altimeter. The maxium takeoff weight of it is 1610kg. When proceeding the typical anti-submarine missions with 40~160km voyage, the MD500MD can remain in flight for 1 hour & 48 mins. Since May 1979, 12 of this variation were deployed in the Taiwan Navy.MD500MD anti-submarine “defenders” is antisubmarine and the water surface search type. Take two crew members on the nose, with the search radar, AN/ASQ-81 drag type magnetic detector, smoke launcher vision, and drop device, emergency floating device, two more Mk44 or Mk46 look for of the torpedo. The vision of the magnetic detecting equipment control box installed in the central control and on the dashboard. Special instrument have a 15.24 centimeters of attitude and radar altimeter indicator. Maximum take-off weight of 1610 grams. In the implementation of typical anti-submarine task, for 40 to 160 km voyage, can stay in the air for 1 hour 48 minutes. In May 1979, China began to delivery to the Taiwan navy 12 frame, equipment in 501, but by a helicopter squadron military ships carrying.

MH-6 special combat helicopters

The MD500MD Defender is the multi purpose military variation. The fuselage & engine are the same with the MD500D. The difference are, self-pressrize fuel tanke and the air inlet strainer. The customer could also ask to add on the armor, blackhole infrared suppresser and hardpoints which can carry TOW and other weapons. MD500MD fits for the missions like training, control & command, light arming attack, anti-submarine, transportation & airborne supply. It can carry seven people including the pilot. The airborne rescue variation can take two pilots, two litters and two nurses. The Korean Aviation Company assembled this version with license.
The MD500MD reconnaissance Defender is a basic military variaion, too. The armament of it are 14 rounds of 2.75 inch rockets & a 7.62mm Minigun with 2000 rounds. Or one 40mm grenade launcher & a 7.62mm EX34 chain gun with 2000 rounds. The Kenya Army bought 15 MD500MD, Korea had 144.

The MD500MD TOW Defender keeps down the nose of the MD500, with a M65 TOW aiming system. Four TOW anti tank missles are fitted on the hardpoints on both sides. Inside the fuselage there are the aiming control system and handrail for the shooter, and control display for the pilot. The engine can be Allison 250-C20, 250-C20R or 250-C30. Israel Airforce had 30 MD500MDs, Kenya had 15 and Korea 50. The MD500MD/MMS TOW is based on MD version with an add on rotor mast aiming system.

Hughes/Douglas MD500/530 series civil helicopters is considered the most excellent many USES one of the helicopter

Hughes/Douglas MD500/530 series is the United States and the international civil helicopters helicopter market very popular a kind of model, is considered the most excellent for one of the helicopter. MD500/530 “defenders” is former hughes helicopter company (August 27, 1985 McDonald Douglas company merged into the MD500/530) in MinYongXing series helicopter developed on the basis of military type. In addition to the “tao” “defenders” outside, its body and civil 500/530 same type. The army Numbers for OH-6 “the pony,” AH-6 and MH-6, nicknamed “little bird”.

At present, our country HongDou aircraft manufacturing companies have in this series of assembly civil the latest variations of the helicopter, and adopted the Boeing/Douglas company’s latest type no tail rotor technology.

MD500M named OH-6 A, 6 series is OH-increase power type, MinYongXing MD500 by it. The engine and the MD500 MinYongXing identical, but the amount of fuel for 227 liters. This type in April 1968 first delivered for use, buy this helicopter country: Japan, Argentina, Bolivia, Denmark, Spain, Mexico and the Philippines. Argentina RACA company and kawasaki heavy industries of Japan patent production company this helicopter, Numbers are 369 HM/OH-6 J (now discontinued) and 369 D/OH-6 D.

OH-and A standard light aviation electronic equipment mainly has: AN/ARC-164 uhf radio communication, AN am/ARC-115 uhf radio communication, AN am/ARC-114 at VHF/FM radio communication, ARN-89 radio compass, APX 72 identification response device, AN/ASN-43 heading gyro, ID 1315 heading direction indicator and C-6533 / ARC machine in the conversation.

Lockheed finally solved all appear flight control problem

Although lockheed finally solved all appear flight control problem, the United States army or the third crash cancelled after the Cheyenne plan, acting with Advanced Attack Helicopter on (on STH, AAH) plan, the simplified fire control system and mature conventional rotor system. Bell’s bidding scheme to condense the AH-1 to all experience, Boeing-childcare scheme adopted his strange like early meters-24 that inclined buy, two pilot two-seater tandem, but about to provide maximum stagger, ahead of the horizon. But several bid, hughes’ AH-64 “apachean” finally win. Later is known as history.

The Cheyenne story is an anticlimactic story. This is a special period, the use of special technology, according to the special requirements of the design of helicopters. AH 64 stick the ground maneuver tactics is proved to be successful, but the Cheyenne high-speed motor tactics are not necessarily will not succeed. The second world war, the United States is the most ace fighter forces are fighting machines, the equipment is not well-known P-51 “wild horse”, but accepted “only speed and climb, no mobility” P-47.

The original version Zemke colonel create “energy” tactics, the combat maneuvering form again and again against the mobility is far excellent Me 109. In contrast, have “the battle of Britain during” the eagle squadron “out of the old machines, equipment have 4 battle of advanced P-51” wild horse, “but instead of the record as Zemke boys. The Cheyenne no such opportunities, the performance and tactics will ever be success has no proof. The Cheyenne died, the concept of rigid rotor is locked into filing cabinet, lockheed never involved in the helicopter fields.

The helicopter mode: no problem. Flight

In addition to the outside of the revolutionary design, the fire is very strong, Cheyenne belly of rotating turret with a 30 mm in aircraft gun, machine spin in the first turret can hold 40 mm automatic grenade launchers or six tubes 7.62 mm machine guns, short Justin gatlin wings can carry a large number of rockets and TOW anti-tank missiles. The fire control system is also very Cheyenne, equipped with advanced terrain tracking radar, laser range finder, night-vision goggles, inertial navigation and other advanced system requirements, not only can do the day and night flight, is also required to post on the flight, with 30 mm gun hit single ground targets.

In a test flight of the Cheyenne begin very successful, will reach the design for the high speed, but the problem soon appeared. In the helicopter flight mode is no problem, in rotorcraft flight mode is no problem, but the problem often out in two modes of the conversion process of transition. From the helicopter mode transition to the rotor machine model, gradually reduce rotor/tail rotor power, increasing the power of the propeller, promote smooth transition word’s ok, but if the conversion of conduct pipe, speed, haven’t go up, short wings to produce enough of the lift, problems will emerge. From rotary-wing mode conversion to helicopters mode, gradually increasing helicopter rotor/tail rotor of power, as well as reduce the power of the propeller, promote if conversion, additional lift of conduct pipe are hard to keep the aircraft flight attitude, and suddenly the resistance of the increase to flight control great difficulties. Even in the helicopter mode, rigid rotor only limited side inverted fly, fly, ability to control ability has been greatly hovering as conventional helicopters. Due to a variety of flight control difficulties, the Cheyenne in test flight for a malignant accident in the news, machine destroyed. The Cheyenne’s too too complex fire control system with many problems, the solution is light-years away.

The Cheyenne see will become beard engineering, the Vietnam war was close, the American attention switched back to Europe. Facing central Europe’s great anti-tank pressure, and increasingly serious Soviet motor anti-aircraft fire (including themselves) and air defense missile and anti-aircraft gun shoulder-fired anti-aircraft missile threat, the U.S. military began to study the stick the ground maneuver as combat helicopter pattern, such, the Cheyenne high speed was not necessary, and the Cheyenne limited unconventional mobility for defects.

The helicopter is not lockheed strengths

The helicopter is not lockheed strengths, but it also makes lockheed let go of burden, lightly. Lockheed from the s to research the rigid rotor (rigid rotor), with a very special gyro linkage system control blade Angle. The rigid rotor simple structure, high strength, maintenance is small, also on the structure allows for higher speed, although the pneumatic rev limit still exists. The rotor in the rise and fall, when power through helicopter use; In the first flight, cut off the power rotor machine use. This can achieve high speed the speed of an airplane and helicopter special maneuver performance of both between effective. The Cheyenne is such a helicopter and rotorcraft mixture. The first design is by lockheed wing tip miniature jet engines provide rotor dynamic, such, can need not offset the torsion of the tail rotor, at the same time by cruise jet engines provide fly before thrust. Power scheme for the more conventional later change inside machine, in the helicopter power mode, and the engine drive the helicopter and the advancement of the tail rotor, propeller do windmills type free choose turn; Before the fly in gyroplane mode, the engine drive the propeller of the helicopter, and tail rotor do windmills spin, fly free type before the state of the lift by short wings have basic.

Even by the standards of the DuoNian 30 after, the Cheyenne is still a revolutionary design. The Cheyenne is worthy of the name “the air tank” maximum take-off weight, up to 13600 kg. By contrast, the Cheyenne “successor”, accepted heavy attack helicopters AH-64 “apachean” maximum take-off weight “only” only 7270 kilograms. The Cheyenne’s top speed to 407 km/hour, AH-64 “apachean” is only 260 km/hour. The first is the state of the rotor machine fly mode, the Cheyenne no helicopter the vibration of the inherent, already has greatly increased the flight of comfort, also greatly improved aircraft gun and missile aiming accuracy.

The Lord of the helicopter rotor is generally not the level

The Lord of the helicopter rotor are usually not level, but slightly in front, used to create lift at the same time, produce thrust. Fly before But to full speed, or before flying upside down, tail up, like the bulls forward as aggressive and do good to sweep the floor, the helicopter to generate more weight, although former fly thrust the windward resistance is bigger. The helicopter’s blades can constantly real-time adjustment blade Angle (official name is paddle distance), large Angle of attack has greater lift, so to sway the lift not balance by or so to achieve, before and after the lift not on the pitch before and after balance to achieve. Blades of Angle constantly adjust is to rely on a top of the inclined cut a top of the “chicken cage” to achieve, a “chicken cage” adjustment all blade Angle, to control the lift and thrust, realize the so-called “total distance control”; Another adjust each oar leaf relative to other blade Angle, to control the plane attitude, realize the so-called “cycle”. Distance Igor west coase in life, the most important invention is this. Blades to the constant change of the Angle that blade aerodynamic load changes, the resulting uninterrupted waving “make” blades must be flexible structure, or strong for the fatigue can make blades in a short time is damaged. It is because of blades uninterrupted “helicopter has inherent, waving” vibrate.

The rotor and “forward” and “final” problem. 360 degrees a whirl, affirmation have half after turn forward from, or so-called move, And the other half was the final turn back, the so-called. Forward, another stage, but to create lift final stage, and produce thrust forward stage not only do not produce thrust, also generate additional resistance. Another have their problems, the first to fly state, the final blades still air relative to the relative speed, low efficiency greatly reduced, serious time may cause stall, but this is another question. In order to reduce drag on, went on stage the propeller blades to decrease, from the leap from increased. OARS But this will cause the imbalance, so about must depend on the flat end to balance, and this is by deflection control surfaces to manufacturing finished resistance, leading to additional aerodynamic drag. RH-66 Ronald koeman’s vertical end has certain Angle, so the way the thrust direction contain the tail rotor and horizontal planes into certain downward Angle is to correct this, about another way to balance. Whatever the way into two steps, this one step back, promote way, always limits the speed of a helicopter.

The speed of a helicopter always mention the not up for another reason, is to improve the diameter of the helicopter and speed is limited. The size of the restrictions is obvious, but also restricted speed, because the rotor diameter, the relations between the speed of the not very tall also can make the wing tip at or more, blade “speed” and waving the rotor speed increase is very limited. The helicopter to produce strong wash of air in the helicopter under forms around the powerful gas act, has greatly increased the resistance of the fly before. Since in the helicopter to “squeeze” on a higher speed, add a special propulsion engines (jet makes or propeller) and the helicopter to “liberate”, dedicated to produce lift and control moment, and push the engine full-time push, which greatly improve speed. Use this composite promote the helicopter known as the compound helicopter way (compound on). Short wings that give priority to, can will unload rotor the helicopter to “liberate” produce more of the thrust, this is another kind of composite helicopter ideas.

In pursuit of high altitude air force to the s

In pursuit of high speed to high altitude air force in the s, the army as a new high speed nature also attack helicopter, the most important requirements, the basic strategy is to use the advantages of speed and climb, good flexibility and firepower, give the enemy with sudden and violent crackdown and minimize exposure to enemy fire under the time. AH-1 the original design is primarily for counterinsurgency and field support design in central Europe, to fight against the Soviet tanks cluster annulled just assault and not to special consideration, new attack helicopter should not only in the field support performance more than AH-1 to outside, but also has the outstanding anti-tank performance at the air combat performance of a helicopter were also requirements.

For such tactics, technical requirements, lockheed a helicopter, the unusual plan put forward by use of the rigid rotor design of composite helicopter scheme. People for fixed wing aircraft and helicopter is very familiar with, but the plane’s extended family, and a forgotten members: the rotor machine (autogyro or gyrocopter). Like a helicopter rotor machine, as in the above have a rotor, in flight rotation in produce lift. The difference is, rotorcraft rotor is without power, in other words, just a forward movement of the windmill, with the wind turns the drive by conventional means of promoting still, such as propellers or jet engine. The rotor machine can’t vertical take-off and landing, but only need a very short taxiing can take off, basic need not taxiing can landing, is the ideal short range and the plane. Lost power, like a helicopter rotor machine can rely on the helicopter to customize landing as, and won’t like fixed wing aircraft crashed as stall. Because without power, the rotor is rotary-wing don’t need tail rotor. If can solve vertical take-off and landing, hovering, side fly, fly down, the ideal of the rotor machine is the aviation high-speed flight platform.

In the s, the helicopter is still the only realistic tradition of vertical take-off and landing technology, service between the political struggle is not allowed to enter the army-that poisson, fighter fixed wing vertical take-off and landing aircraft. The traditional helicopter rotor Lord is a fully expert, already used to produce the lift, and used to produce thrust and roll torque. This feature is the tendency of the helicopter and, and, and, and the source of mobility helicopter in speed and on the handling of an infinite number of the fundamental problem.

The Vietnam war is the first time in history, the helicopter war

The Vietnam war is the first time in history, the war in Vietnam, the United States helicopter battlefield from H-used to 21 “flight to CH-47 banana” “hello Mr G” to CH-53 “green giant” (code name is “kind of formal horse”) to OH-6 of the helicopter, used to support JiJiang infantry combat, and the most famous of these is undoubtedly UH-1 “huey”. In combat, the U.S. military quickly adopted by the French in Algeria guerrilla combat experience, started in the doors installation machine guns, used as a helicopter and suppression fires on the screen.

But this is, after all, an expedient measure. U.S. soon started to develop special attack helicopters, the request has better than “huey” the level of general helicopters have stronger firepower, motor and protection, bell helicopter company AH-1 “huey cobra” solution to the fore. AH-1 in UH-1 is the machinery and power systems, has developed on with modern attack helicopter is the main feature of the fuselage with armor, narrow: protection, serial two-seater, the nose of the rotating turret below fitted with multiple tube machine guns, on both sides of the body on the rockets and missiles. But AH-1 is as a transitional attack helicopter, and the design idea of the ideal American troops also differs very far, so U.S. troops immediately set out to Advanced air Fire Support System (Aerial Fire on teachers, AAFSS) plan, the System AH-56 “Cheyenne” came into being.

The Cheyenne was a strange political restrictions and technical innovation of the product. Vietnam the battlefield of the American army need most is able to vertical take-off and landing, suitable for low flying low speed, strong, mobility, fire armored thick modern Doyle-2 JiangJiJi to today’s point of view, may have the armor-is the most appropriate choice of fighter jets. But after the war the national defense law of the air force to create provisions shall not be involved in the plane of the army in design, procurement and deployment, the helicopter is a legal did not make clear a regulation, the exception in a infighting in the army after residents. Even so, the air force to the army to design field support plane or great dissatisfaction.

RAH-66 “for Ronald koeman’s” helicopter provides a PAGAN 18 against interference navigation system

A recent American thunder of British subsidiary company the thunder system Co., LTD. (RSL) won a pre-production contract, for 66 “Ronald koeman’s RAH-” helicopter provides a PAGAN 18 against interference navigation system. The contract is worth 2.2 million pounds, including hardware delivery, project management and limit. Mass production is likely to start in the middle of 2004.

PAGAN is small four channel the jamming system, and is suitable for small platform. The system to eliminate the GPS signal and natural damage the interference of existence and development, to be able to handle any direction from the many sources. PAGAN typical platform including ground vehicles, helicopters, and uavs and surface vessel, and a small fighter.

Recent RAH-66 increase with cone-shaped mast-heads, improving the MMW radar at night and bad weather of combat.

The us army there is attention RAH-66 project, the project may face funding problems was cancelled because of the bad luck. The army has put “Ronald koeman’s” comprehensive equipment for the troops from 2008 years time delay to 2009, and eased RAH-part of the weapon and 66 equipped with the requirements of the system, in order to reduce the risk of development. After adjusting the research and development funds are still as much as $3.4 billion.

But in April 2002, the house armed services committee (HASC) submit fiscal 2003 defense authorization bill, which rejected the army in recent change RAH-66 plan idea. Bill will urge the army establish specialized RAH-66 plan, to supplement the test of the grant. HASC support the plan, but not tolerate the army and contractors on the plan and HASC bargain. HASC hope to have an elaborate organization of RAH-66 plan. According to the requirements of the HASC, army must increase financial support to reduce risk, delay arrangement plan of the increase of flight test time and spiral development requirements, reach the level of military forces target new contract requirements, as well as the relevant s best function to the contract below cost increase problem.