Misplaced Pages

#978021

98-586: The Ilyushin Il-102 is a Soviet experimental jet-powered ground-attack aircraft designed by Ilyushin . This aircraft was never chosen for production, being surpassed by the Su-25 . Only a few development prototypes were built. In 1967, the Soviet Air Forces drew up a specification for a jet-powered shturmovik or armoured ground attack aircraft. While Sukhoi designed an all-new single seat aircraft,

196-399: A convergent-divergent nozzle is needed on high-speed aircraft. The engine thrust is highest if the static pressure of the gas reaches the ambient value as it leaves the nozzle. This only happens if the nozzle exit area is the correct value for the nozzle pressure ratio (npr). Since the npr changes with engine thrust setting and flight speed this is seldom the case. Also at supersonic speeds

294-680: A rotating air compressor powered by a turbine , with the leftover power providing thrust through the propelling nozzle —this process is known as the Brayton thermodynamic cycle . Jet aircraft use such engines for long-distance travel. Early jet aircraft used turbojet engines that were relatively inefficient for subsonic flight. Most modern subsonic jet aircraft use more complex high-bypass turbofan engines . They give higher speed and greater fuel efficiency than piston and propeller aeroengines over long distances. A few air-breathing engines made for high-speed applications (ramjets and scramjets ) use

392-603: A 102mm anti-ship cannon, The BK 7,5 was unsurpassed as an aircraft-fitted gun until 1971, when the four-engine Lockheed AC-130 E Spectre; equipped with a 105 mm M102 howitzer , entered service with the US Air Force.) In the immediate post war era the piston-engined ground-attack aircraft remained useful since all of the early jets lacked endurance due to the fuel consumption rates of the jet engines. The higher powered piston engine types that had been too late for World War II were still capable of holding their own against

490-450: A battlefield, their slower speeds made them extremely vulnerable to ground fire, as did the lighter construction of fighters. The survivability of attack aircraft was guaranteed by their speed/power, protection (i.e. armor panels) and strength of construction; Germany was the first country to produce dedicated ground-attack aircraft (designated CL-class and J-class ). They were put into use in autumn 1917, during World War I. Most notable

588-605: A class of Schlacht ("battle") aircraft, such as the Henschel Hs 123 . Moreover, the experiences of German Condor Legion during the Spanish Civil War , against an enemy with few fighter aircraft, changed ideas about ground attack. Though equipped with generally unsuitable designs such as the Henschel Hs 123 and cannon -armed versions of the Heinkel He 112 , their armament and pilots proved that aircraft were

686-408: A compressor ( axial , centrifugal , or both), mixing fuel with the compressed air, burning the mixture in the combustor , and then passing the hot, high pressure air through a turbine and a nozzle . The compressor is powered by the turbine, which extracts energy from the expanding gas passing through it. The engine converts internal energy in the fuel to increased momentum of the gas flowing through

784-604: A high altitude bomber escort, but gradually found that role filled by the North American P-51 Mustang (because of its much longer range and greater maneuverability). The P-47 was also heavier and more robust than the P-51 and regarded therefore, as an " energy fighter ": ideal for high-speed dive-and-climb tactics, including strafing attacks. Its armament of eight 0.50 caliber machine guns was effective against Axis infantry and light vehicles in both Europe and

882-427: A higher priority than fuel efficiency, fans tend to be smaller or absent. Because of these distinctions, turbofan engine designs are often categorized as low-bypass or high-bypass , depending upon the amount of air which bypasses the core of the engine. Low-bypass turbofans have a bypass ratio of around 2:1 or less. The term Advanced technology engine refers to the modern generation of jet engines. The principle

980-406: A jet of water. The mechanical arrangement may be a ducted propeller with nozzle, or a centrifugal compressor and nozzle. The pump-jet must be driven by a separate engine such as a Diesel or gas turbine . All jet engines are reaction engines that generate thrust by emitting a jet of fluid rearwards at relatively high speed. The forces on the inside of the engine needed to create this jet give

1078-404: A lack of Air Force enthusiasm for the ground-attack role, developed the dedicated attack helicopter . On 17 January 1991, Task Force Normandy began its attack on two Iraqi anti-aircraft missile sites. TF Normandy, under the command of LTC Richard A. "Dick" Cody , consisted of nine AH-64 Apaches , one UH-60 Black Hawk and four Air Force MH-53J Pave Low helicopters. The purpose of this mission

SECTION 10

#1732782599979

1176-426: A large number of different types of jet engines, all of which achieve forward thrust from the principle of jet propulsion . Commonly aircraft are propelled by airbreathing jet engines. Most airbreathing jet engines that are in use are turbofan jet engines, which give good efficiency at speeds just below the speed of sound. A turbojet engine is a gas turbine engine that works by compressing air with an inlet and

1274-675: A light aircraft mixing all the roles that required extensive communication with land forces: reconnaissance, liaison, artillery spotting , aerial supply, and, last but not least, occasional strikes on the battlefield. The concept was similar to front-line aircraft used in the World War I, which was called the CL class in the German Empire. Eventually the RAF's experience showed types such as Westland Lysander to be unacceptably vulnerable and it

1372-670: A light attack aircraft. The Soviets' similar Sukhoi Su-25 ( Frogfoot ) found success in the "flying artillery" role with many air forces. The UK has completely retired the BAE Harrier II in 2011, and the Panavia Tornado dedicated attack-reconnaissance aircraft in 2019. It obtained the F-35 in 2018 and it retains its fleet of Eurofighter Typhoon multirole fighters. [REDACTED] Media related to Attack aircraft at Wikimedia Commons Jet engine A jet engine

1470-435: A particular engine design that if some bumps in a bypass duct are smoothed out the air will flow more smoothly giving a pressure loss reduction of x% and y% less fuel will be needed to get the take-off thrust, for example. This understanding comes under the engineering discipline Jet engine performance . How efficiency is affected by forward speed and by supplying energy to aircraft systems is mentioned later. The efficiency of

1568-759: A powerplant for the world's first jet- fighter aircraft , the Messerschmitt Me 262 (and later the world's first jet- bomber aircraft, the Arado Ar 234 ). A variety of reasons conspired to delay the engine's availability, causing the fighter to arrive too late to improve Germany's position in World War II , however this was the first jet engine to be used in service. Meanwhile, in Britain the Gloster E28/39 had its maiden flight on 15 May 1941 and

1666-521: A second airframe built for static tests, and carried out 250 test flights until it was grounded in 1984 when the engine life expired. The Il-102 was a low-winged monoplane with moderately swept (30 degrees) wings, powered by two Klimov RD-33 I turbofans (non-afterburning versions of the engines that power the Mikoyan MiG-29 fighter). It was highly unusual for its time in having a rear gun turret , something not seen in ground-attack aircraft since

1764-410: A separate attack aircraft category was greatly diminished by the introduction of precision-guided munitions which allowed almost any aircraft to carry out this role while remaining safe at high altitude. Attack helicopters also have overtaken many remaining roles that could only be carried out at lower altitudes. Since the 1960s, only two dedicated attack aircraft designs have been widely introduced,

1862-530: A strong thrust on the engine which pushes the craft forwards. Jet engines make their jet from propellant stored in tanks that are attached to the engine (as in a 'rocket') as well as in duct engines (those commonly used on aircraft) by ingesting an external fluid (very typically air) and expelling it at higher speed. A propelling nozzle produces a high velocity exhaust jet . Propelling nozzles turn internal and pressure energy into high velocity kinetic energy. The total pressure and temperature don't change through

1960-439: A substantial initial forward airspeed before it can function. Ramjets are considered the simplest type of air breathing jet engine because they have no moving parts in the engine proper, only in the accessories. Scramjets differ mainly in the fact that the air does not slow to subsonic speeds. Rather, they use supersonic combustion. They are efficient at even higher speed. Very few have been built or flown. The rocket engine uses

2058-421: A supersonic afterburning engine or 2200 K with afterburner lit. The pressure entering the nozzle may vary from 1.5 times the pressure outside the nozzle, for a single stage fan, to 30 times for the fastest manned aircraft at Mach 3+. Convergent nozzles are only able to accelerate the gas up to local sonic (Mach 1) conditions. To reach high flight speeds, even greater exhaust velocities are required, and so

SECTION 20

#1732782599979

2156-639: A task of converted trainers, like the BAE Systems Hawk or Aero L-39 Albatros , and many trainers are built with this task in mind, like the CASA C-101 or the Aermacchi MB-339 . Such counter-insurgency aircraft are popular with air forces which cannot afford to purchase more expensive multirole aircraft, or do not wish to risk the few such aircraft they have on light ground attack missions. A proliferation of low intensity conflicts in

2254-402: A test stand, sucks in fuel and generates thrust. How well it does this is judged by how much fuel it uses and what force is required to restrain it. This is a measure of its efficiency. If something deteriorates inside the engine (known as performance deterioration ) it will be less efficient and this will show when the fuel produces less thrust. If a change is made to an internal part which allows

2352-461: A two-stage axial compressor feeding a single-sided centrifugal compressor . Practical axial compressors were made possible by ideas from A.A.Griffith in a seminal paper in 1926 ("An Aerodynamic Theory of Turbine Design"). Whittle would later concentrate on the simpler centrifugal compressor only. Whittle was unable to interest the government in his invention, and development continued at a slow pace. In Spain, pilot and engineer Virgilio Leret Ruiz

2450-483: A very effective weapon, even without bombs. This led to some support within the Luftwaffe for the creation of an aircraft dedicated to this role, resulting in tenders for a new "attack aircraft". This led to the introduction (in 1942) of a unique single-seat, twin-engine attack aircraft, the slow-moving but heavily armored and formidably armed Henschel Hs 129 Panzerknacker ("Safecracker" /"Tank Cracker"). In Japan,

2548-493: Is a type of reaction engine , discharging a fast-moving jet of heated gas (usually air) that generates thrust by jet propulsion . While this broad definition may include rocket , water jet , and hybrid propulsion, the term jet engine typically refers to an internal combustion air-breathing jet engine such as a turbojet , turbofan , ramjet , pulse jet , or scramjet . In general, jet engines are internal combustion engines . Air-breathing jet engines typically feature

2646-426: Is considered an attack mission . In United States Navy vocabulary, the alternative designation for the same activity is a strike mission . Attack missions are principally divided into two categories: air interdiction and close air support . In the last several decades, the rise of the ubiquitous multi-role fighter has created some confusion about the difference between attack and fighter aircraft. According to

2744-507: Is documented in the story of Ottoman soldier Lagâri Hasan Çelebi , who reportedly achieved flight using a cone-shaped rocket in 1633. The earliest attempts at airbreathing jet engines were hybrid designs in which an external power source first compressed air, which was then mixed with fuel and burned for jet thrust. The Italian Caproni Campini N.1 , and the Japanese Tsu-11 engine intended to power Ohka kamikaze planes towards

2842-443: Is that a turbine engine will function more efficiently if the various sets of turbines can revolve at their individual optimum speeds, instead of at the same speed. The true advanced technology engine has a triple spool, meaning that instead of having a single drive shaft, there are three, in order that the three sets of blades may revolve at different speeds. An interim state is a twin-spool engine, allowing only two different speeds for

2940-400: Is the propellant flow in kg/s, A e {\displaystyle A_{e}} is the cross-sectional area at the exit of the exhaust nozzle, and p {\displaystyle p} is the atmospheric pressure. Combined-cycle engines simultaneously use two or more different principles of jet propulsion. A water jet, or pump-jet, is a marine propulsion system that uses

3038-570: Is used for launching satellites, space exploration and crewed access, and permitted landing on the Moon in 1969. Rocket engines are used for high altitude flights, or anywhere where very high accelerations are needed since rocket engines themselves have a very high thrust-to-weight ratio . However, the high exhaust speed and the heavier, oxidizer-rich propellant results in far more propellant use than turbofans. Even so, at extremely high speeds they become energy-efficient. An approximate equation for

Ilyushin Il-102 - Misplaced Pages Continue

3136-710: The F-111 "Aardvark" was designated F despite having only minimal air-to-air capabilities. Only a single aircraft in the USAF's current inventory bears a simple, unmixed "A" designation: the A-10 Thunderbolt II. British designations have included FB for fighter-bomber and more recently "G" for "Ground-attack" as in Harrier GR1 (meaning "Ground-attack/Reconnaissance, Mark 1"). Imperial Japanese Navy designation use "B" to designate carrier attack bomber such as

3234-903: The Gloster Meteor finally entered service with the RAF in July 1944. These were powered by turbojet engines from Power Jets Ltd., set up by Frank Whittle. The first two operational turbojet aircraft, the Messerschmitt Me 262 and then the Gloster Meteor entered service within three months of each other in 1944; the Me 262 in April and the Gloster Meteor in July. The Meteor only saw around 15 aircraft enter World War II action, while up to 1400 Me 262 were produced, with 300 entering combat, delivering

3332-442: The Henschel Hs 123 ). Although not a synonymous class with ground-attack aircraft, fighter-bombers were usually used for the role, and proved to excel at it, even when they were only lightly armored. The Royal Air Force and United States Army Air Forces relegated obsolescent fighters to this role, while cutting-edge fighters would serve as interceptors and establish air superiority . The United States Navy , in distinction to

3430-768: The Imperial Japanese Navy had developed the Aichi D3A dive bomber (based on the Heinkel He 70 ) and the Mitsubishi B5M light attack bomber. Both, like their US counterparts, were lightly armored types, and were critically reliant on surprise attacks and the absence of significant fighter or AA opposition. During the Winter War , the Soviet Air Forces used the Polikarpov R-5 SSS, and Polikarpov R-Z Sh, as attack aircraft. Perhaps

3528-791: The Junkers Ju 87 Stuka greatly outnumbered the Hs 129, while the Petlyakov Pe-2 was used for this role in spite of not being specifically designed for it. In the latter part of World War II, the fighter-bomber began to take over many attack roles, a transition that continued in the post-war era. Jet -powered examples were relatively rare but not unknown, such as the Blackburn Buccaneer . The U.S. Navy continued to introduce new aircraft in their A - series , but these were mostly similar to light and medium bombers . The need for

3626-1017: The Nakajima B5N Type-97 bomber although these aircraft are mostly used for torpedo attack and level bombing. They also use "D" to specifically designate carrier dive bomber like the Yokosuka D4Y Suisei . However by the end of the world war II, the IJN introduced the Aichi B7A Ryusei which could performed both torpedo bombing and dive bombing rendering the "D" designation redundant. The NATO reporting names for Soviet/Russian ground-attack aircraft at first started with "B" categorizing them as bombers, as in case of Il-10 'Beast'. But later they were usually classified as fighters ("F")—possibly because (since Sukhoi Su-7 ) they were similar in size and visual appearance to Soviet fighters, or were simply derivatives of such. In

3724-608: The North American B-25G Mitchell and de Havilland Mosquito Tsetse . In Germany and the USSR , where they were known as Schlachtflugzeug ("battle aircraft") or sturmovik ("storm trooper") respectively, this role was carried out by purpose-designed and heavily armored aircraft such as the Henschel Hs 129 and Ilyushin Il-2 . The Germans and Soviets also used light bombers in this role: cannon-armed versions of

3822-667: The PLAAF , ground-attack aircraft are given the designation "Q". So far this has only been given to the Nanchang Q-5 . The attack aircraft as a role was defined by its use during World War I , in support of ground forces on battlefields. Battlefield support is generally divided into close air support and battlefield air interdiction, the first requiring strict and the latter only general cooperation with friendly surface forces. Such aircraft also attacked targets in rear areas. Such missions required flying where light anti-aircraft fire

3920-721: The Pacific . While machine guns and cannon were initially sufficient, the evolution of well-armored tanks required heavier weapons. To augment bombs, high explosive rockets were introduced, although these unguided projectiles were still "barely adequate" because of their inaccuracy. For the British RP3 , one hit per sortie was considered acceptable. However, even a near miss with rockets could cause damage or injuries to "soft targets," and patrols by Allied rocket-armed aircraft over Normandy disrupted or even completely paralyzed German road traffic. They also affected morale, because even

4018-530: The Su-25 , Ilyushin proposed a modified version of their Il-40 of 1953 under the designation Il-42 , which, unlike the Sukhoi, was a two-seat aircraft with a remotely-controlled rear gun turret. The design was rejected by the Soviet Air Forces, but Ilyushin decided to continue in-house development regardless, renaming the programme Il-102 . The Il-102 first prototype flew on 25 September 1982, with

Ilyushin Il-102 - Misplaced Pages Continue

4116-605: The United States occupation of Haiti and Nicaragua . The United States Army Air Corps was notable for its creation of a separate "A-" designation for attack types, distinct from and alongside "B-" for bomber types and "P-" for pursuit (later replaced by "F-" for fighter) aircraft. The first designated attack type to be operational with the USAAC was the Curtiss A-2 Falcon . Nevertheless, such aircraft, including

4214-540: The World War II Il-2 Shturmovik and Il-10 , the Il-102's spiritual ancestors, controlled remotely by a gunner sitting in a cockpit above the trailing edge of the wing. The crew cockpits, engines and fuel tanks were armoured to protect against ground fire. Although development was abandoned in 1984, the prototype Il-102 was publicly unveiled at the 1992 Mosaeroshow air show at Zhukovsky , being claimed to be available for export. As of 2005,

4312-500: The aeolipile , a device described by Hero of Alexandria in 1st-century Egypt . This device directed steam power through two nozzles to cause a sphere to spin rapidly on its axis. It was seen as a curiosity. Meanwhile, practical applications of the turbine can be seen in the water wheel and the windmill . Historians have further traced the theoretical origin of the principles of jet engines to traditional Chinese firework and rocket propulsion systems. Such devices' use for flight

4410-564: The carrier-based nuclear strike Douglas A-3 Skywarrior and North American A-5 Vigilante , while the Grumman A-6 Intruder , F-105 Thunderchief , F-111 , F-117 Nighthawk , LTV A-7 Corsair II , Sukhoi Su-25 , A-10 Thunderbolt II , Panavia Tornado , AMX , Dassault Étendard , Super Étendard and others were designed specifically for ground-attack, strike , close support and anti-armor work, with little or no air-to-air capability. Ground attack has increasingly become

4508-664: The gasoline -fuelled HeS 3 of 5 kN (1,100 lbf), which was fitted to Heinkel's simple and compact He 178 airframe and flown by Erich Warsitz in the early morning of August 27, 1939, from Rostock -Marienehe aerodrome , an impressively short time for development. The He 178 was the world's first jet plane. Heinkel applied for a US patent covering the Aircraft Power Plant by Hans Joachim Pabst von Ohain on May 31, 1939; patent number US2256198, with M Hahn referenced as inventor. Von Ohain's design, an axial-flow engine, as opposed to Whittle's centrifugal flow engine,

4606-558: The interdiction and tactical bombing roles. Today it remains the only dedicated fixed-wing ground-attack aircraft in any U.S. military service. Overall U.S. experience in the Gulf War , Kosovo War , Afghanistan War , and Iraq War has resulted in renewed interest in such aircraft. The U.S. Air Force is currently researching a replacement for the A-10 and started the OA-X program to procure

4704-402: The ram effect of the vehicle's speed instead of a mechanical compressor. The thrust of a typical jetliner engine went from 5,000 lbf (22 kN) ( de Havilland Ghost turbojet) in the 1950s to 115,000 lbf (510 kN) ( General Electric GE90 turbofan) in the 1990s, and their reliability went from 40 in-flight shutdowns per 100,000 engine flight hours to less than 1 per 100,000 in

4802-481: The " Night Witches " utilised an obsolescent, wooden light trainer biplane type, the Polikarpov Po-2 and small anti-personnel bombs in "harassment bombing" attacks that proved difficult to counter. Wartime experience showed that poorly armored and/or lightly built, pre-war types were unacceptably vulnerable, especially to fighters. Nevertheless, skilled crews could be highly successful in those types, such as

4900-591: The 1,420 maritime strike variants of the North American B-25 Mitchell G/H, which mounted either a M4 cannon , or light-weight T13E1 or M5 versions of the same gun. These weapons, however, were hand-loaded, had shorter barrels and/or a lower muzzle velocity than the BK 7,5 and, therefore, poorer armor penetration, accuracy and rate of fire. (Except for versions of the Piaggio P.108 armed with

4998-537: The 1950s, the jet engine was almost universal in combat aircraft, with the exception of cargo, liaison and other specialty types. By this point, some of the British designs were already cleared for civilian use, and had appeared on early models like the de Havilland Comet and Avro Canada Jetliner . By the 1960s, all large civilian aircraft were also jet powered, leaving the piston engine in low-cost niche roles such as cargo flights. The efficiency of turbojet engines

SECTION 50

#1732782599979

5096-588: The A-2's replacement, the Curtiss A-12 Shrike , were unarmored and highly vulnerable to AA fire. The British Royal Air Force focused primarily on strategic bombing, rather than ground attack. However, like most air arms of the period it did operate attack aircraft, named Army Cooperation in RAF parlance, which included the Hawker Hector , Westland Lysander and others. Aviation played a role in

5194-662: The American Fairchild Republic A-10 Thunderbolt II and the Soviet/Russian Sukhoi Su-25 Frogfoot. A variety of light attack aircraft has also been introduced in the post-World War II era, usually based on adapted trainers or other light fixed-wing aircraft. These have been used in counter-insurgency operations. U.S. attack aircraft are currently identified by the prefix A- , as in " A-6 Intruder " and " A-10 Thunderbolt II ". However, until

5292-684: The Brazilian Constitutionalist Revolution of 1932 , although both sides had few aircraft. The federal government had approximately 58 aircraft divided between the Navy and the Army , as the Air Force at this time did not constitute an independent branch. In contrast, the rebels had only two Potez 25 planes and two Waco CSO , plus a small number of private aircraft. During the 1930s, Nazi Germany had begun to field

5390-521: The British embassy in Madrid a few years later by his wife, Carlota O'Neill , upon her release from prison. In 1935, Hans von Ohain started work on a similar design to Whittle's in Germany, both compressor and turbine being radial, on opposite sides of the same disc, initially unaware of Whittle's work. Von Ohain's first device was strictly experimental and could run only under external power, but he

5488-694: The German Focke-Wulf Fw 190 , the British Hawker Typhoon and the US Republic P-47 Thunderbolt . The Typhoon, which was disappointing as a fighter, due to poor high altitude performance, was very fast at low altitudes and thus became the RAF's premier ground attack fighter. It was armed with four 20mm cannon , augmented first with bombs, then rockets. Likewise the P-47 was designed and intended for use as

5586-534: The Pratt & Whitney J57 and J75 models. There is also a derivative of the P&;W JT8D low-bypass turbofan that creates up to 35,000 horsepower (HP) . Jet engines are also sometimes developed into, or share certain components such as engine cores, with turboshaft and turboprop engines, which are forms of gas turbine engines that are typically used to power helicopters and some propeller-driven aircraft. There are

5684-672: The U.S. Marine Corps has noted similar problems. In the late 1960s the United States Air Force requested a dedicated close air support (CAS) plane that became the Fairchild Republic A-10 Thunderbolt II . The A-10 was originally conceived as an anti-armor weapon (the A-X program requirements specifically called for an aircraft mounting a large rotary cannon to destroy massed Warsaw Pact armored forces) with limited secondary capability in

5782-602: The USAAF, preferred the older term "Scout-Bomber", under a "SB-" designation, such as the Curtiss SB2C Helldiver . The Junkers Ju 87s of the German Luftwaffe became virtually synonymous with close air support during the early months of World War II. The British Commonwealth's Desert Air Force , led by Arthur Tedder, became the first Allied tactical formation to emphasize the attack role, usually in

5880-685: The USAAF. It was not until 1946, when the US Navy and US Marine Corps started using the "attack" (A) designation, when it renamed BT2D Skyraider and BTM Mauler to, respectively, AD Skyraider and AM Mauler. As with many aircraft classifications, the definition of attack aircraft is somewhat vague and has tended to change over time. Current U.S. military doctrine defines it as an aircraft which most likely performs an attack mission , more than any other kind of mission. Attack mission means, in turn, specifically tactical air-to-ground action—in other words, neither air-to-air action nor strategic bombing

5978-400: The air/combustion gases to flow more smoothly the engine will be more efficient and use less fuel. A standard definition is used to assess how different things change engine efficiency and also to allow comparisons to be made between different engines. This definition is called specific fuel consumption , or how much fuel is needed to produce one unit of thrust. For example, it will be known for

SECTION 60

#1732782599979

6076-541: The class. Strike fighters , which have effectively replaced the fighter-bomber and light bomber concepts, also differ little from the broad concept of an attack aircraft. The dedicated attack aircraft as a separate class existed primarily during and after World War II . The precise implementation varied from country to country, and was handled by a wide variety of designs. In the United States and Britain , attack aircraft were generally light bombers or medium bombers , sometimes carrying heavier forward-firing weapons like

6174-666: The current U.S. designation system, an attack aircraft ( A ) is designed primarily for air-to-surface (Attack: Aircraft designed to find, attack, and destroy land or sea targets) missions (also known as "attack missions"), while a fighter category F incorporates not only aircraft designed primarily for air-to-air combat , but additionally multipurpose aircraft designed also for ground-attack missions. "F" - Fighter Aircraft were designed to intercept and destroy other aircraft or missiles. This includes multipurpose aircraft also designed for ground support missions such as interdiction and close air support. Just to mention one example amongst many,

6272-496: The divergent area is less than required to give complete internal expansion to ambient pressure as a trade-off with external body drag. Whitford gives the F-16 as an example. Other underexpanded examples were the XB-70 and SR-71. The nozzle size, together with the area of the turbine nozzles, determines the operating pressure of the compressor. This overview highlights where energy losses occur in complete jet aircraft powerplants or engine installations. A jet engine at rest, as on

6370-412: The end of World War II the A- designation was shared between attack planes and light bombers for USAAF aircraft (as opposed to B- prefix for medium or heavy bombers). The US Navy used a separate designation system and at the time preferred to call similar aircraft scout bombers (SB) or torpedo bombers (TB or BT). For example, Douglas SBD Dauntless scout bomber was designated A-24 when used by

6468-405: The end of World War II were unsuccessful. Even before the start of World War II, engineers were beginning to realize that engines driving propellers were approaching limits due to issues related to propeller efficiency, which declined as blade tips approached the speed of sound . If aircraft performance were to increase beyond such a barrier, a different propulsion mechanism was necessary. This

6566-425: The engine is controlled primarily by the operating conditions inside the engine which are the pressure produced by the compressor and the temperature of the combustion gases at the first set of rotating turbine blades. The pressure is the highest air pressure in the engine. The turbine rotor temperature is not the highest in the engine but is the highest at which energy transfer takes place ( higher temperatures occur in

6664-650: The engine, producing thrust. All the air entering the compressor is passed through the combustor, and turbine, unlike the turbofan engine described below. Turbofans differ from turbojets in that they have an additional fan at the front of the engine, which accelerates air in a duct bypassing the core gas turbine engine. Turbofans are the dominant engine type for medium and long-range airliners . Turbofans are usually more efficient than turbojets at subsonic speeds, but at high speeds their large frontal area generates more drag . Therefore, in supersonic flight, and in military and other aircraft where other considerations have

6762-414: The first ground attacks and air combat victories of jet planes. Following the end of the war the German jet aircraft and jet engines were extensively studied by the victorious allies and contributed to work on early Soviet and US jet fighters. The legacy of the axial-flow engine is seen in the fact that practically all jet engines on fixed-wing aircraft have had some inspiration from this design. By

6860-712: The form of rocket engines they power model rocketry , spaceflight , and military missiles . Jet engines have propelled high speed cars, particularly drag racers , with the all-time record held by a rocket car . A turbofan powered car, ThrustSSC , currently holds the land speed record . Jet engine designs are frequently modified for non-aircraft applications, as industrial gas turbines or marine powerplants . These are used in electrical power generation, for powering water, natural gas, or oil pumps, and providing propulsion for ships and locomotives. Industrial gas turbines can create up to 50,000 shaft horsepower. Many of these engines are derived from older military turbojets such as

6958-419: The form of single-engine Hawker Hurricane and Curtiss P-40 fighter-bombers or specialized "tank-busters", such as the Hurricane Mk IID, armed with two 40 mm Vickers S guns (notably No. 6 Squadron RAF ). At around the same time, a massive invasion by Axis forces had forced the Soviet air forces to quickly expand their army support capacity, such as the Ilyushin Il-2 Sturmovik. The women pilots known as

7056-602: The jets as they were able to both out accelerate and out maneuver the jets. The Royal Navy Hawker Sea Fury fighters and the U.S. Vought F4U Corsair and Douglas A-1 Skyraider were operated during the Korean War while the latter continued to be used throughout the Vietnam War . Many post-World War II era air forces have been reluctant to adopt fixed-wing jet aircraft developed specifically for ground attack. Although close air support and interdiction remain crucial to

7154-458: The late 1990s. This, combined with greatly decreased fuel consumption, permitted routine transatlantic flight by twin-engined airliners by the turn of the century, where previously a similar journey would have required multiple fuel stops. The principle of the jet engine is not new; however, the technical advances necessary to make the idea work did not come to fruition until the 20th century. A rudimentary demonstration of jet power dates back to

7252-487: The leading Stuka ace, Hans-Ulrich Rudel , who claimed 500 tanks, a battleship, a cruiser, and two destroyers in 2,300 combat missions. The Bristol Beaufighter , based on an obsolescent RAF bomber, became a versatile twin-engine attack aircraft and served in almost every theatre of the war, in the maritime strike and ground attack roles as well as that of night fighter. Conversely, some mid-war attack types emerged as adaptations of fighters, including several versions of

7350-462: The modern battlefield, attack aircraft are less glamorous than fighters, while air force pilots and military planners have a certain well-cultivated contempt for "mud-movers". More practically, the cost of operating a specialized ground-attack aircraft is harder to justify when compared with multirole combat aircraft . Jet attack aircraft were designed and employed during the Cold War era, such as

7448-574: The most notable attack type to emerge during the late 1930s was the Soviet Ilyushin Il-2 Sturmovik , which became the most-produced military aircraft type in history. As World War II approached, the concept of an attack aircraft was not well defined, and various air services used many different names for widely differing types, all performing similar roles (sometimes in tandem with non-attack roles of bombers, fighters, reconnaissance and other roles. The British concept of

7546-394: The net thrust of a rocket engine is: Where F N {\displaystyle F_{N}} is the net thrust, I sp,vac {\displaystyle I_{\text{sp,vac}}} is the specific impulse , g 0 {\displaystyle g_{0}} is a standard gravity , m ˙ {\displaystyle {\dot {m}}}

7644-404: The nozzle but their static values drop as the gas speeds up. The velocity of the air entering the nozzle is low, about Mach 0.4, a prerequisite for minimizing pressure losses in the duct leading to the nozzle. The temperature entering the nozzle may be as low as sea level ambient for a fan nozzle in the cold air at cruise altitudes. It may be as high as the 1000 Kelvin exhaust gas temperature for

7742-518: The post-World War II era has also expanded need for these types of aircraft to conduct counter-insurgency and light ground attack operations. A primary distinction of post-World War II aviation between the U.S. Army and the U.S. Air Force was that latter had generally been allocated all fixed-wing aircraft , while helicopters were under control of the former; this was governed by the 1948 Key West Agreement . The Army, wishing to have its own resources to support its troops in combat and faced with

7840-512: The prospect of a rocket attack was unnerving. The ultimate development of the cannon-armed light attack aircraft was the small production run in 1944 of the Henschel Hs 129 B-3, armed with a modified PAK 40 75 mm anti-tank gun. This weapon, the Bordkanone BK 7,5 , was the most powerful forward-firing weapon fitted to a production military aircraft during World War II. The only other aircraft to be factory-equipped with similar guns were

7938-625: The prototype No. 10201 was placed on display at the Gromov Flight Research Institute . Data from The Osprey Encyclopedia of Russian Aircraft 1875–1995 General characteristics Performance Armament Related development Aircraft of comparable role, configuration, and era Ground-attack aircraft Fighter aircraft often carry out the attack role, although they would not be considered attack aircraft per se ; fighter-bomber conversions of those same aircraft would be considered part of

8036-424: The same basic physical principles of thrust as a form of reaction engine , but is distinct from the jet engine in that it does not require atmospheric air to provide oxygen; the rocket carries all components of the reaction mass. However some definitions treat it as a form of jet propulsion . Because rockets do not breathe air, this allows them to operate at arbitrary altitudes and in space. This type of engine

8134-509: The specification was dropped before an aircraft went into production. In some air services, dive bombers did not equip ground-attack units, but were treated as a separate class. In Nazi Germany, the Luftwaffe distinguished between the Stuka ( Sturzkampf- , "dive bombing") units, equipped with Junkers Ju 87 from Schlacht ("battle") units, using strafing/low-level bombing types such as

8232-539: The state of the art in compressors. Alan Arnold Griffith published An Aerodynamic Theory of Turbine Design in 1926 leading to experimental work at the RAE . In 1928, RAF College Cranwell cadet Frank Whittle formally submitted his ideas for a turbojet to his superiors. In October 1929, he developed his ideas further. On 16 January 1930, in England, Whittle submitted his first patent (granted in 1932). The patent showed

8330-432: The turbines. Ram compression jet engines are airbreathing engines similar to gas turbine engines in so far as they both use the Brayton cycle . Gas turbine and ram compression engines differ, however, in how they compress the incoming airflow. Whereas gas turbine engines use axial or centrifugal compressors to compress incoming air, ram engines rely only on air compressed in the inlet or diffuser. A ram engine thus requires

8428-621: Was a part of the Allied armies' strength in holding German attacks and supporting Allied counter-attacks and offensives. Admittedly, the cost to the Allies was high, with the Royal Flying Corps sustaining a loss rate approaching 30% among ground-attack aircraft. After World War I, it was widely believed that using aircraft against tactical targets was of little use other than in harassing and undermining enemy morale; attacking combatants

8526-604: Was able to demonstrate the basic concept. Ohain was then introduced to Ernst Heinkel , one of the larger aircraft industrialists of the day, who immediately saw the promise of the design. Heinkel had recently purchased the Hirth engine company, and Ohain and his master machinist Max Hahn were set up there as a new division of the Hirth company. They had their first HeS 1 centrifugal engine running by September 1937. Unlike Whittle's design, Ohain used hydrogen as fuel, supplied under external pressure. Their subsequent designs culminated in

8624-499: Was an armored twin-engine triplane for ground strafing with eight machine guns and about a ton of armor plate, and the 1922 Aeromarine PG-1 was a combined pursuit (fighter) and ground attack design with a 37mm gun. The United States Marine Corps Aviation applied close air support tactics in the Banana Wars . While they did not pioneer dive bombing tactics, Marine aviators were the first to include it in their doctrine during

8722-406: Was built in 1903 by Norwegian engineer Ægidius Elling . Such engines did not reach manufacture due to issues of safety, reliability, weight and, especially, sustained operation. The first patent for using a gas turbine to power an aircraft was filed in 1921 by Maxime Guillaume . His engine was an axial-flow turbojet, but was never constructed, as it would have required considerable advances over

8820-578: Was eventually adopted by most manufacturers by the 1950s. Austrian Anselm Franz of Junkers ' engine division ( Junkers Motoren or "Jumo") introduced the axial-flow compressor in their jet engine. Jumo was assigned the next engine number in the RLM 109-0xx numbering sequence for gas turbine aircraft powerplants, "004", and the result was the Jumo 004 engine. After many lesser technical difficulties were solved, mass production of this engine started in 1944 as

8918-475: Was expected and operating at low altitudes to precisely identify targets. Other roles, including those of light bombers , medium bombers , dive bombers , reconnaissance , fighters , fighter-bombers , could and did perform air strikes on battlefields. All these types could significantly damage ground targets from a low level flight, either by bombing, machine guns, or both. Attack aircraft came to diverge from bombers and fighters. While bombers could be used on

9016-689: Was generally much more dangerous to aircrews than their targets, a problem that was continually becoming more acute with the ongoing refinement of anti-aircraft weapons . Within the range of types serving attack roles, dive bombers were increasingly being seen as more effective than aircraft designed for strafing with machine guns or cannons . Nevertheless, during the 1920s, the US military, in particular, procured specialized "Attack" aircraft and formed dedicated units, that were trained primarily for that role. The US Army Engineering Division became involved in designing ground attack aircraft. The 1920 Boeing GA-1

9114-526: Was granted a patent for a jet engine design in March 1935. Republican president Manuel Azaña arranged for initial construction at the Hispano-Suiza aircraft factory in Madrid in 1936, but Leret was executed months later by Francoist Moroccan troops after unsuccessfully defending his seaplane base on the first days of the Spanish Civil War . His plans, hidden from Francoists, were secretly given to

9212-530: Was replaced by faster fighter types for photo-reconnaissance, and light aircraft for artillery spotting. During the inter-war period, the British flew the Fairey Battle , a light bomber which originated in a 1932 specification. Designs in 1938 for a replacement were adapted as a target tug. The last British specification issued for a light bomber was B.20/40 described as a "Close Army Support Bomber" capable of dive bombing and photo-reconnaissance. However,

9310-427: Was still rather worse than piston engines, but by the 1970s, with the advent of high-bypass turbofan jet engines (an innovation not foreseen by the early commentators such as Edgar Buckingham , at high speeds and high altitudes that seemed absurd to them), fuel efficiency was about the same as the best piston and propeller engines. Jet engines power jet aircraft , cruise missiles and unmanned aerial vehicles . In

9408-780: Was the Junkers J.I , which pioneered the idea of an armored "bathtub", that was both fuselage structure and protection for engine and crew. The British experimented with the Sopwith TF series (termed "trench fighters"), although these did not see combat. The last battles of 1918 on the Western Front demonstrated that ground-attacking aircraft were a valuable component of all-arms tactics. Close support ground strafing ( machine-gunning ) and tactical bombing of infantry (especially when moving between trenches and along roads), machine gun posts , artillery , and supply formations

9506-409: Was the motivation behind the development of the gas turbine engine, the most common form of jet engine. The key to a practical jet engine was the gas turbine , extracting power from the engine itself to drive the compressor . The gas turbine was not a new idea: the patent for a stationary turbine was granted to John Barber in England in 1791. The first gas turbine to successfully run self-sustaining

9604-852: Was to create a safe corridor through the Iraqi air defense system. The attack was a huge success and cleared the way for the beginning of the Allied bombing campaign of Operation Desert Storm . One concern involving the Apache arose when a unit of these helicopters was very slow to deploy during U.S. military involvement in Kosovo. According to the Army Times , the Army is shifting its doctrine to favor ground-attack aircraft over attack helicopters for deep strike attack missions because ground-attack helicopters have proved to be highly vulnerable to small-arms fire;

#978021