Bell AH-1Z Viper
The Bell AH-1Z Viper is an American twin-engine attack helicopter, based on the AH-1W SuperCobra, developed for the United States Marine Corps as part of the H-1 upgrade program. The AH-1Z features a four-blade, composite main rotor system, uprated transmission, a new target sighting system; the AH-1Z, one of the latest members of the prolific Huey family, is called "Zulu Cobra", based on the military phonetic alphabet pronunciation of its variant letter. Aspects of the AH-1Z date back to the Bell 249 in 1979, an AH-1S equipped with the four-blade main rotor system from the Bell 412; this helicopter demonstrated Bell's Cobra II design at the Farnborough Airshow in 1980. The Cobra II was to be equipped with a new targeting system and improved engines. Came the Cobra 2000 proposal which included General Electric T700 engines and a four-blade rotor; this design drew interest from the US Marine Corps. In 1993, Bell proposed an AH-1W-based version for the UK's new attack helicopter program; the derivative design, named CobraVenom, featured a modern digital cockpit and could carry TOWs, Hellfire or Brimstone missiles.
The CobraVenom design was altered in 1995 by changing to a four-blade rotor system. The design lost to the AH-64D that year however. In 1996, the USMC launched the H-1 upgrade program by signing a contract with Bell Helicopter for upgrading 180 AH-1Ws into AH-1Zs and upgrading 100 UH-1Ns into UH-1Ys; the H-1 program created modernized attack and utility helicopters with considerable design commonality to reduce operating costs. The AH-1Z and UH-1Y share a common tailboom, rotor system, avionics architecture, software and displays for over 84% identical components. Bell participated in a joint Bell-Government integrated test team during the engineering manufacturing development phase of the H-1 program; the AH-1Z program progressed from 1996 to 2003 as a research and development operation. The existing two-blade semi-rigid, teetering rotor system is being replaced with a four-blade, bearingless rotor system; the four-blade configuration provides improvements in flight characteristics including increased flight envelope, maximum speed, vertical rate of climb and reduced rotor vibration level.
The AH-1Z first flew on 8 December 2000. Bell delivered three prototype aircraft to the United States Navy's Naval Air Systems Command at Naval Air Station Patuxent River in July 2002, for the flight test phase of the program. Low-rate initial production began in October 2003, with deliveries to run through 2018. In late 2006 NAVAIR awarded a contract to Meggitt Defense Systems to develop a new linkless 20 mm ammunition handling system to improve on the gun feed reliability of the existing linked feed system; these systems are now being retrofitted into the AH-1W and AH-1Z fleets with good results during combat in Afghanistan. In February 2008, the U. S. Navy adjusted the contract so the last 40 AH-1Zs are built as new airframes instead of the planned rebuild of AH-1Ws. In September 2008, the Navy requested an additional 46 airframes for the Marine Corps, bringing the total number ordered to 226. In 2010, the Marine Corps planned to order 189 AH-1Zs with 58 of them being new airframes, with deliveries to continue until 2022.
On 10 December 2010, the Department of the Navy approved the AH-1Z for full-rate production. The AH-1Z incorporates new rotor technology with upgraded military avionics, weapons systems, electro-optical sensors in an integrated weapons platform, it has improved survivability and can find targets at longer ranges and attack them with precision weapons. The AH-1Z's new bearingless, hingeless rotor system has 75% fewer parts than that of four-bladed articulated systems; the blades are made of composites, which have an increased ballistic survivability, there is a semiautomatic folding system for storage aboard amphibious assault ships. Its two redesigned wing stubs are longer, with each adding a wingtip station for a missile such as the AIM-9 Sidewinder; each wing has two other stations for 2.75-inch Hydra 70 rocket pods, or AGM-114 Hellfire quad missile launchers. The AN/APG-78 Longbow fire control radar can be mounted on a wingtip station; the Z-model's integrated avionics system has been developed by Northrop Grumman.
The system includes an automatic flight control system. Each crew station has two 8×6-inch multifunction liquid crystal displays and one 4.2×4.2-inch dual function LCD. The communications suite combines a US Navy RT-1824 integrated radio, UHF/VHF, COMSEC and modem in a single unit; the navigation suite includes an embedded GPS inertial navigation system, a digital map system and Meggitt's low-airspeed air data subsystem, which allows weapons delivery when hovering. The crew are equipped with the Thales "Top Owl" helmet-mounted display system; the Top Owl has a binocular display with a 40 ° field of view. Its visor projection provides forward looking infrared or video imagery; the AH-1Z has survivability equipment including the Hover Infrared Suppression System to cover engine exhausts, countermeasure dispensers, radar warning, incoming/on-way missile warning, on-fuselage laser spot warning systems. The Lockheed Martin Target Sight System incorporates a third-generation FLIR sensor; the TSS provides target sighting in night, or adverse weather conditions.
The system has various view modes and can track with FLIR or by TV. The same system is used on the KC-130J Harvest HAWK; the AH-1Z completed sea-trial flight testing in May 2005. On 15 October 2005, the USMC, through the Naval Air Systems Com
In military munitions, a fuze is the part of the device that initiates function. In some applications, such as torpedoes, a fuze may be identified by function as the exploder; the relative complexity of the earliest fuze designs can be seen in cutaway diagrams. A fuze is a device. In addition, a fuze will have safety and arming mechanisms that protect users from premature or accidental detonation. For example, an artillery fuze's battery is activated by the high acceleration of cannon launch, the fuze must be spinning before it will function. "Complete bore safety" can be achieved with mechanical shutters that isolate the detonator from the main charge until the shell is fired. A fuze may contain only the electronic or mechanical elements necessary to signal or actuate the detonator, but some fuzes contain a small amount of primary explosive to initiate the detonation. Fuzes for large explosive charges may include an explosive booster. Professional publications about explosives and munitions distinguish the "fuse" and "fuze" spelling.
The UK Ministry of Defence states: FUSE: Cord or tube for the transmission of flame or explosion consisting of cord or rope with gunpowder or high explosive spun into it. FUZE: A device with explosive components designed to initiate a main charge. Oliver Hogg states the following about fuze: The word "fuze" is spelt "fuse" by those unaquainted with artillery usage; this is incorrect. "Fuse", derived from fusus, the past participle of fundo, means "to melt", e.g. the term "fuse-wire" used in electrical circuits. "Fuze", on the other hand, is the shortened or modern method of spelling "fuzee", meaning a tube filled with combustible material. It is a derivation of a spindle and from the French fusee, a spindle full of thread, it is well to make this point at the outset. It was spelled with either's' or'z', both spellings can still be found. In the United States and some military forces, fuze is used to denote a sophisticated ignition device incorporating mechanical and/or electronic components as opposed to a simple burning fuse.
The situation of usage and the characteristics of the munition it is intended to activate affect the fuze design e.g. its safety and actuation mechanisms. Artillery fuzes are tailored to function in the special circumstances of artillery projectiles; the relevant factors are the projectile's initial rapid acceleration, high velocity and rapid rotation, which affect both safety and arming requirements and options, the target may be moving or stationary. Artillery fuzes may be initiated by a timer mechanism, impact or detection of proximity to the target, or a combination of these. Requirements for a hand grenade fuze are defined by the projectile's small size and slow delivery over a short distance; this necessitates manual arming before throwing as the grenade has insufficient initial acceleration for arming to be driven by "setback" and no rotation to drive arming by centrifugal force. Aerial bombs can be detonated either by a fuze, which contains a small explosive charge to initiate the main charge, or by a "pistol", a firing pin in a case which strikes the detonator when triggered.
The pistol may be considered a part of the mechanical fuze assembly. The main design consideration is that the bomb that the fuze is intended to actuate is stationary, the target itself is moving in making contact. Relevant design factors in naval mine fuzes are that the mine may be static or moving downward through the water, the target is moving on or below the water surface above the mine. Time fuzes detonate after a set period of time by using one or more combinations of mechanical, pyrotechnic or chemical timers. Depending on the technology used, the device may self-destruct some seconds, hours, days, or months after being deployed. Early artillery time fuzes were nothing more than a hole filled with gunpowder leading from the surface to the centre of the projectile; the flame from the burning of the gunpowder propellant ignited this "fuze" on firing, burned through to the centre during flight igniting or exploding whatever the projectile may have been filled with. By the 19th century devices more recognisable as modern artillery "fuzes" were being made of selected wood and trimmed to burn for a predictable time after firing.
These were still fired from smoothbore muzzle-loaders with a large gap between the shell and barrel, still relied on flame from the gunpowder propellant charge escaping past the shell on firing to ignite the wood fuze and hence initiate the timer. In the mid-to-late 19th century adjustable metal time fuzes, the fore-runners of today's time fuzes, containing burning gunpowder as the delay mechanism became common, in conjunction with the introduction of rifled artillery. Rifled guns introduced a tight fit between shell and barrel and hence could no longer rely on the flame from the propellant to initiate the timer; the new metal fuzes use the shock of firing and/or the projectiles's rotation to "arm" the fuze and initiate the timer: hence introducing a safety factor absent. During World War I, mechanical, or clockwork, time fuzes were introduced for artillery by Germany, some variants are still in use; as late
General Dynamics F-16 Fighting Falcon
The General Dynamics F-16 Fighting Falcon is a single-engine supersonic multirole fighter aircraft developed by General Dynamics for the United States Air Force. Designed as an air superiority day fighter, it evolved into a successful all-weather multirole aircraft. Over 4,600 aircraft have been built since production was approved in 1976. Although no longer being purchased by the U. S. Air Force, improved versions are being built for export customers. In 1993, General Dynamics sold its aircraft manufacturing business to the Lockheed Corporation, which in turn became part of Lockheed Martin after a 1995 merger with Martin Marietta; the Fighting Falcon's key features include a frameless bubble canopy for better visibility, side-mounted control stick to ease control while maneuvering, an ejection seat reclined 30 degrees from vertical to reduce the effect of g-forces on the pilot, the first use of a relaxed static stability/fly-by-wire flight control system which helps to make it a nimble aircraft.
The F-16 has an internal M61 Vulcan cannon and 11 locations for mounting weapons and other mission equipment. The F-16's official name is "Fighting Falcon", but "Viper" is used by its pilots and crews, due to a perceived resemblance to a viper snake as well as the Colonial Viper starfighter on Battlestar Galactica which aired around when the F-16 entered service. In addition to active duty in the U. S. Air Force, Air Force Reserve Command, Air National Guard units, the aircraft is used by the USAF aerial demonstration team, the U. S. Air Force Thunderbirds, as an adversary/aggressor aircraft by the United States Navy; the F-16 has been procured to serve in the air forces of 25 other nations. As of 2015, it is the world's most numerous fixed-wing aircraft in military service. Experiences in the Vietnam War revealed the need for air superiority fighters and better air-to-air training for fighter pilots. Based on his experiences in the Korean War and as a fighter tactics instructor in the early 1960s, Colonel John Boyd with mathematician Thomas Christie developed the energy–maneuverability theory to model a fighter aircraft's performance in combat.
Boyd's work called for a small, lightweight aircraft that could maneuver with the minimum possible energy loss, which incorporated an increased thrust-to-weight ratio. In the late 1960s, Boyd gathered a group of like-minded innovators who became known as the Fighter Mafia, in 1969, they secured Department of Defense funding for General Dynamics and Northrop to study design concepts based on the theory. Air Force F-X proponents remained hostile to the concept because they perceived it as a threat to the F-15 program. However, the Air Force's leadership understood that its budget would not allow it to purchase enough F-15 aircraft to satisfy all of its missions; the Advanced Day Fighter concept, renamed F-XX, gained civilian political support under the reform-minded Deputy Secretary of Defense David Packard, who favored the idea of competitive prototyping. As a result, in May 1971, the Air Force Prototype Study Group was established, with Boyd a key member, two of its six proposals would be funded, one being the Lightweight Fighter.
The Request for Proposals issued on 6 January 1972 called for a 20,000-pound class air-to-air day fighter with a good turn rate and range, optimized for combat at speeds of Mach 0.6–1.6 and altitudes of 30,000–40,000 feet. This was the region; the anticipated average flyaway cost of a production version was $3 million. This production plan, was only notional, as the USAF had no firm plans to procure the winner. Five companies responded, in 1972, the Air Staff selected General Dynamics' Model 401 and Northrop's P-600 for the follow-on prototype development and testing phase. GD and Northrop were awarded contracts worth $37.9 million and $39.8 million to produce the YF-16 and YF-17 with first flights of both prototypes planned for early 1974. To overcome resistance in the Air Force hierarchy, the Fighter Mafia and other LWF proponents advocated the idea of complementary fighters in a high-cost/low-cost force mix; the "high/low mix" would allow the USAF to be able to afford sufficient fighters for its overall fighter force structure requirements.
The mix gained broad acceptance by the time of the prototypes' flyoff, defining the relationship of the LWF and the F-15. The YF-16 was developed by a team of General Dynamics engineers led by Robert H. Widmer; the first YF-16 was rolled out on 13 December 1973. Its 90-minute maiden flight was made at the Air Force Flight Test Center at Edwards AFB, California, on 2 February 1974, its actual first flight occurred accidentally during a high-speed taxi test on 20 January 1974. While gathering speed, a roll-control oscillation caused a fin of the port-side wingtip-mounted missile and the starboard stabilator to scrape the ground, the aircraft began to veer off the runway; the test pilot, Phil Oestricher, decided to lift off to avoid a potential crash, safely landing six minutes later. The slight damage was repaired and the official first flight occurred on time; the YF-16's first supersonic flight was accomplished on 5 February 1974, the second YF-16 prototype first flew on 9 May 1974. This was followed by the first flights of Northrop's YF-17 prototypes on 9 June and 21 August 1974, respectively.
During the flyoff, the YF-16s completed 330 sorties for a total of 417 flight hours. Increased interest turned the LWF into a serious acquisition program. North Atlantic Treaty Organization allies Belgium, the Netherlands, Norway were seeking to replace their
Bell OH-58 Kiowa
The Bell OH-58 Kiowa is a family of single-engine, single-rotor, military helicopters used for observation and direct fire support. Bell Helicopter manufactured the OH-58 for the United States Army based on its Model 206A JetRanger helicopter; the OH-58 was in continuous U. S. Army service from 1969 to 2017; the latest model, the OH-58D Kiowa Warrior, is operated in an armed reconnaissance role in support of ground troops. The OH-58 has been exported to Austria, Croatia, the Dominican Republic, Saudi Arabia, Greece, it has been produced under license in Australia. On 14 October 1960, the United States Navy asked 25 helicopter manufacturers on behalf of the Army for proposals for a Light Observation Helicopter. Bell Helicopter entered the competition along with 12 other manufacturers, including Hiller Aircraft and Hughes Tool Co. Aircraft Division. Bell submitted the D-250 design, which would be designated as the YHO-4. On 19 May 1961, Hiller were announced as winners of the design competition. Bell developed the D-250 design into the Model 206 aircraft, with the HO-4 designation being changed to YOH-4A in 1962, produced five prototype aircraft for the Army's test and evaluation phase.
The first prototype flew on 8 December 1962. The YOH-4A became known as the Ugly Duckling in comparison to the other contending aircraft. Following a flyoff of the Bell and Fairchild-Hiller prototypes, the Hughes OH-6 Cayuse was selected in May 1965; when the YOH-4A was rejected by the Army, Bell went about solving the problem of marketing the aircraft. In addition to the image problem, the helicopter lacked cargo space and only provided cramped quarters for the planned three passengers in the back; the solution was a fuselage redesigned to be more sleek and aesthetic, adding 16 cubic feet of cargo space in the process. The redesigned aircraft was designated as the Model 206A, Bell President Edwin J. Ducayet named it the JetRanger denoting an evolution from the popular Model 47J Ranger. In 1967, the Army reopened the LOH competition for bids because Hughes Tool Co. Aircraft Division could not meet the contractual production demands. Bell resubmitted for the program using the Bell 206A. Fairchild-Hiller failed to resubmit their bid with the YOH-5A, which they had marketed as the FH-1100.
In the end, Bell underbid Hughes to win the contract and the Bell 206A was designated as the OH-58A. Following the U. S. Army's naming convention for helicopters, the OH-58A was named Kiowa in honor of the Native American tribe. In the 1970s, the U. S. Army began evaluating the need to improve the capabilities of their scout aircraft. Anticipating the AH-64A's replacement of the venerable AH-1, the Army began shopping the idea of an Aerial Scout Program to stimulate the development of advanced technological capabilities for night vision and precision navigation equipment; the stated goals of the program included prototypes that would: "...possess an extended target acquisition range capability by means of a long-range stabilized optical subsystem for the observer, improved position location through use of a computerized navigation system, improved survivability by reducing aural, visual and infrared signatures, an improved flight performance capability derived from a larger engine to provide compatibility with attack helicopters".
The Army created a special task force at Fort Knox to develop the system requirements in early March 1974, by 1975 the task force had devised the requirements for an Advanced Scout Helicopter program. The requirements were formulated around an aircraft capable of performing in day and adverse weather, compatible with all the advanced weapons systems planned for development and fielding into the 1980s; the program was approved by the System Acquisition Review Council and the Army prepared for competitive development to begin the next year. However, as the Army tried to get the program off the ground, Congress declined to provide funding for it in the fiscal year 1977 budget and the ASH Project Manager's Office was closed on 30 September 1976. While no development occurred during the next few years, the program survived as a requirement without funding. On 30 November 1979, the decision was made to defer development of an advanced scout helicopter in favor of pursuing modification of existing airframes in the inventory as a near term scout helicopter option.
The development of a mast-mounted sight would be the primary focus to improve the aircraft's ability to perform reconnaissance and target acquisition missions while remaining hidden behind trees and terrain. Both the UH-1 and the OH-58 were evaluated as NTSH candidates, but the UH-1 was dropped from consideration due to its larger size and ease of detection; the OH-58, on the other hand demonstrated a dramatic reduction in detectability with a Mast-Mounted Sight. On 10 July 1980, the Army decided that the NTSH would be a competitive modification program based on developments in the commercial helicopter industry Hughes Helicopters development of the Hughes 500D which provided significant improvements over the OH-6; the Army's decision to acquire the NTSH resulted in the "Army Helicopter Improvement Program". Both Bell Helicopter and Hughes Helicopters redesigned their scout aircraft to compete for the contract. Bell offered a more robust version of the OH-58 in their model 406 aircraft, Hughes offered an upgraded version of the OH-6.
On 21 September 1981, Bell Helicopter Textron was awarded a development contract. The first prototype flew on 6 October 1983, the aircraft entered service in 1985 as the OH-58D. Intended for attack and artillery roles, the Army o
Folding-Fin Aerial Rocket
The Mk 4 Folding-Fin Aerial Rocket known as Mighty Mouse, was an unguided rocket used by United States military aircraft. 2.75 inches in diameter, it was designed as an air-to-air weapon for interceptor aircraft to shoot down enemy bombers, but saw service as an air-to-surface weapon. The advent of jet engines for fighters and bombers posed new problems for interceptors. With closing speeds of 1,500 ft/s or more for a head-on interception, the time available for a fighter pilot to target an enemy aircraft and inflict sufficient damage to bring it down was vanishingly small. Wartime experience had shown that.50 caliber machine guns were not powerful enough to reliably down a bomber not in a single volley, heavy autocannon did not have the range or rate of fire to ensure a hit. Unguided rockets had been proven effective in ground-attack work during the war, the Luftwaffe had shown that volleys of their Werfer-Granate 21 rockets, first used by elements of the Luftwaffe's JG 1 and JG 11 fighter wings on July 29, 1943 against USAAF bombers attacking Kiel and Warnemünde, could be a potent air-to-air weapon.
The summer and autumn of 1944 saw the adoption of the folding-fin R4M unguided rocket for use underneath the wings of the Messerschmitt Me 262 jet fighter for bomber destroyer duties against the USAAF's Eighth Air Force heavy bombers. The FFAR was developed in the late 1940s by the US Navy Naval Ordnance Test Center and North American Aviation. Mass production was established at the facilities of the Norris-Thermador Corp. Los Angeles, the Hunter Douglas Division of the Bridgeport Brass Co. Riverside, California Fuzes were manufactured by the Bulova Watch Co. Jackson Heights, Queens, N. Y. with rocket propellant supplied by Hercules Inc. Wilmington, metal parts supplied by Aerojet General, Downey and miscellaneous spare parts were made by North American Aviation; the original Mk 4 FFAR was about 4 ft long and weighed 18.5 lb, with a high-explosive warhead of about 6 lb. Like the Third Reich Luftwaffe's R4M projectile of World War II, it had folding fins that flipped out on launch to spin-stabilize the rocket, with the FFAR using half the number of fins in comparison to the R4M's set of eight folding fins.
Its maximum effective range was about 3,700 yards. Because of its low intrinsic accuracy, it was fired in large volleys, some aircraft carrying as many as 104 rockets. FFARs were the primary armament of many NATO interceptor aircraft in the early 1950s, including the F-86D, F-89, F-94C, the CF-100, they were carried by the F-102 Delta Dagger to supplement its guided missile armament. The Mk 4 was dubbed "Mighty Mouse" in service, after the popular Mighty Mouse cartoon character; the Mighty Mouse was to prove a poor aerial weapon. Although it was powerful enough to destroy a bomber with a single hit, its accuracy was abysmal, its spin rate was not high enough to compensate for the effects of wind and gravity drop, the rockets dispersed on launch: a volley of 24 rockets would cover an area the size of a football field. As a result, by the late 1950s it had been abandoned as an aircraft weapon in favor of the guided air-to-air missiles becoming available; the Mk 4 found other uses, however, as an air-to-ground weapon for the new breed of armed helicopter.
A volley of FFARs was as devastating as a heavy cannon with far less weight and recoil, in the ground-attack role its marginal long-range accuracy was less important. It was fitted with a more powerful motor to become the Mk 40; the Mk 40 was a universal motor developed from the Mk 4 2.75 FFAR, could be fitted with different warheads depending on the mission. Pods were created for various applications, a wide variety of specialized warheads were developed for antipersonnel and target-marking use; the FFAR has been developed into the modern Hydra 70 series, still in service. The United States was the primary user of this type of weapon and developed a number of different launching pods for it. LAU-3 pods were constructed of aluminum-reinforced cardboard and were intended to be disposed of either on the ground after a mission or by dropping them in-flight. With the advent of the armed helicopter, the increased usage during the Viet Nam War, the need for launching pods that were reusable became apparent, so that models were of all-metal construction.
Though the rocket was developed by the US Navy, the US Air Force and US Army were most responsible for the development of rocket pods for all services. These pods are described as follows: Launchers designated under the US Air Force system: Launchers designated under the US Army system: Early UH-1B/UH-1C Gunships had the XM-3 Subsystem using paired 24 round rectangular launchers mounted near the back edge of the sliding side doors; these pods were semi-permanent aircraft parts. The mounting point had been used to mount booms for 3 SS-11 Launchers on each side for anti-tank missions; the co-pilot had a roof mounted control box to fire these. UH-1C and D aircraft had a mount on each side to carry a 7-round pod coupled with paired M-60D machine guns; some carried M-134 Miniguns with 3000 rounds per gun instead, though these aircraft were used by Air Cavalry units, not the Aerial Rocket Artillery units. Various ground launchers using discarded aircraft pods were used for fire base defence. A towed configuration consisting of six 19-round pods called a Slammer was tested for airborne infantry support.
The range was 7000 meters using Hydra 70 family rockets. With the development of the Mk 40 Mod 0 universal motor c
A helicopter is a type of rotorcraft in which lift and thrust are supplied by rotors. This allows the helicopter to take off and land vertically, to hover, to fly forward and laterally; these attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of VTOL aircraft cannot perform. The English word helicopter is adapted from the French word hélicoptère, coined by Gustave Ponton d'Amécourt in 1861, which originates from the Greek helix "helix, whirl, convolution" and pteron "wing". English language nicknames for helicopter include "chopper", "copter", "helo", "heli", "whirlybird". Helicopters were developed and built during the first half-century of flight, with the Focke-Wulf Fw 61 being the first operational helicopter in 1936; some 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 most earlier designs used more than one main rotor, it is the single main rotor with anti-torque tail rotor configuration that has become the most common helicopter configuration.
Tandem rotor helicopters are in widespread use due to their greater payload capacity. Coaxial helicopters, tiltrotor aircraft, compound helicopters are all flying today. Quadcopter helicopters pioneered as early as 1907 in France, other types of multicopter have been developed for specialized applications such as unmanned drones; the earliest references for vertical flight came from China. Since around 400 BC, Chinese children have played with bamboo flying toys; this bamboo-copter is spun by rolling a stick attached to a rotor. The spinning creates lift, the toy flies when released; the 4th-century AD Daoist book Baopuzi by Ge Hong describes some of the ideas inherent to rotary wing aircraft. Designs similar to the Chinese helicopter toy appeared in some Renaissance paintings and other works. In the 18th and early 19th centuries Western scientists developed flying machines based on the Chinese toy, it was not until the early 1480s, when Italian polymath Leonardo da Vinci created a design for a machine that could be described as an "aerial screw", that any recorded advancement was made towards vertical flight.
His notes suggested that he built small flying models, but there were no indications for any provision to stop the rotor from making the craft rotate. As scientific knowledge increased and became more accepted, people continued to pursue the idea of vertical flight. In July 1754, Russian Mikhail Lomonosov had developed a small coaxial modeled after the Chinese top but powered by a wound-up spring device and demonstrated it to the Russian Academy of Sciences, it was powered by a spring, was suggested as a method to lift meteorological instruments. In 1783, Christian de Launoy, his mechanic, used a coaxial version of the Chinese top in a model consisting of contrarotating turkey flight feathers as rotor blades, in 1784, demonstrated it to the French Academy of Sciences. Sir George Cayley, influenced by a childhood fascination with the Chinese flying top, developed a model of feathers, similar to that of Launoy and Bienvenu, but powered by rubber bands. By the end of the century, he had progressed to using sheets of tin for rotor blades and springs for power.
His writings on his experiments and models would become influential on future aviation pioneers. Alphonse Pénaud would develop coaxial rotor model helicopter toys in 1870 powered by rubber bands. One of these toys, given as a gift by their father, would inspire the Wright brothers to pursue the dream of flight. In 1861, the word "helicopter" was coined by Gustave de Ponton d'Amécourt, a French inventor who demonstrated a small steam-powered model. While celebrated as an innovative use of a new metal, the model never lifted off the ground. D'Amecourt's linguistic contribution would survive to describe the vertical flight he had envisioned. Steam power was popular with other inventors as well. In 1878 the Italian Enrico Forlanini's unmanned vehicle powered by a steam engine, rose to a height of 12 meters, where it hovered for some 20 seconds after a vertical take-off. Emmanuel Dieuaide's steam-powered design featured counter-rotating rotors powered through a hose from a boiler on the ground. In 1887 Parisian inventor, Gustave built and flew a tethered electric model helicopter.
In July 1901, the maiden flight of Hermann Ganswindt's helicopter took place in Berlin-Schöneberg. A movie covering the event was taken by Max Skladanowsky. In 1885, Thomas Edison was given US$1,000 by James Gordon Bennett, Jr. to conduct experiments towards developing flight. Edison built a helicopter and used the paper for a stock ticker to create guncotton, with which he attempted to power an internal combustion engine; the helicopter was damaged by explosions and one of his workers was badly burned. Edison reported that it would take a motor with a ratio of three to four pounds per horsepower produced to be successful, based on his experiments. Ján Bahýľ, a Slovak inventor, adapted the internal combustion engine to power his helicopter model that reached a height of 0.5 meters in 1901. On 5 May 1905, his helicopter flew for over 1,500 meters. In 1908, Edison patented his own design for a helicopter powered by a gasoline engine with box kites attached to a mast by cables for a rotor, but it never flew.
In 1906, two French brothers and Louis Breguet, began experimenting with airfoils for helicopters. In
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. It is the largest and most capable navy in the world and it has been estimated that in terms of tonnage of its active battle fleet alone, it is larger than the next 13 navies combined, which includes 11 U. S. allies or partner nations. With the highest combined battle fleet tonnage and the world's largest aircraft carrier fleet, with eleven in service, two new carriers under construction. With 319,421 personnel on active duty and 99,616 in the Ready Reserve, the Navy is the third largest of the service branches, it has 282 deployable combat vessels and more than 3,700 operational aircraft as of March 2018, making it the second-largest air force in the world, after the United States Air Force. The U. S. Navy traces its origins to the Continental Navy, established during the American Revolutionary War and was disbanded as a separate entity shortly thereafter.
The U. S. Navy played a major role in the American Civil War by blockading the Confederacy and seizing control of its rivers, it played the central role in the World War II defeat of Imperial Japan. The US Navy emerged from World War II as the most powerful navy in the world; the 21st century U. S. Navy maintains a sizable global presence, deploying in strength in such areas as the Western Pacific, the Mediterranean, the Indian Ocean, it is a blue-water navy with the ability to project force onto the littoral regions of the world, engage in forward deployments during peacetime and respond to regional crises, making it a frequent actor in U. S. foreign and military policy. The Navy is administratively managed by the Department of the Navy, headed by the civilian Secretary of the Navy; the Department of the Navy is itself a division of the Department of Defense, headed by the Secretary of Defense. The Chief of Naval Operations is the most senior naval officer serving in the Department of the Navy.
The mission of the Navy is to maintain and equip combat-ready Naval forces capable of winning wars, deterring aggression and maintaining freedom of the seas. The U. S. Navy is a seaborne branch of the military of the United States; the Navy's three primary areas of responsibility: The preparation of naval forces necessary for the effective prosecution of war. The maintenance of naval aviation, including land-based naval aviation, air transport essential for naval operations, all air weapons and air techniques involved in the operations and activities of the Navy; the development of aircraft, tactics, technique and equipment of naval combat and service elements. U. S. Navy training manuals state that the mission of the U. S. Armed Forces is "to be prepared to conduct prompt and sustained combat operations in support of the national interest." As part of that establishment, the U. S. Navy's functions comprise sea control, power projection and nuclear deterrence, in addition to "sealift" duties, it follows as certain as that night succeeds the day, that without a decisive naval force we can do nothing definitive, with it, everything honorable and glorious.
Naval power... is the natural defense of the United States The Navy was rooted in the colonial seafaring tradition, which produced a large community of sailors and shipbuilders. In the early stages of the American Revolutionary War, Massachusetts had its own Massachusetts Naval Militia; the rationale for establishing a national navy was debated in the Second Continental Congress. Supporters argued that a navy would protect shipping, defend the coast, make it easier to seek out support from foreign countries. Detractors countered that challenging the British Royal Navy the world's preeminent naval power, was a foolish undertaking. Commander in Chief George Washington resolved the debate when he commissioned the ocean-going schooner USS Hannah to interdict British merchant ships and reported the captures to the Congress. On 13 October 1775, the Continental Congress authorized the purchase of two vessels to be armed for a cruise against British merchant ships. S. Navy; the Continental Navy achieved mixed results.
In August 1785, after the Revolutionary War had drawn to a close, Congress had sold Alliance, the last ship remaining in the Continental Navy due to a lack of funds to maintain the ship or support a navy. In 1972, the Chief of Naval Operations, Admiral Elmo Zumwalt, authorized the Navy to celebrate its birthday on 13 October to honor the establishment of the Continental Navy in 1775; the United States was without a navy for nearly a decade, a state of affairs that exposed U. S. maritime merchant ships to a series of attacks by the Barbary pirates. The sole armed maritime presence between 1790 and the launching of the U. S. Navy's first warships in 1797 was the U. S. Revenue-Marine, the primary predecessor of the U. S. Coast Guard. Although the USRCS conducted operations against the pirates, their depredations far outstripped its abilities and Congress passed the Naval Act of 1794 that established a permanent standing navy on 27 March 1794; the Naval Act ordered the construction and manning of six frigates and, by October 1797, the first three were brought into service: USS United States, USS Constellation, USS Constitution.
Due to his strong posture on having a strong standing Navy during this period, John Adams is "often called the father of the American Navy". In 1798–99 the Navy was involved in an undeclared Quasi-War with France. From 18