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Ilyushin Il-40
The Ilyushin Il-40 (NATO reporting name: Brawny) was a two-seat Soviet jet-engined armored ground-attack aircraft. The first prototype flew in 1953 and was very successful except when it fired its guns, as their combustion gasses disturbed the airflow into the engines and caused them to flameout or hiccup. Remedying this problem took over a year and involved the radical change of moving the engine air intakes all the way to the very front of the aircraft and repositioning the guns from the tip of the nose to the bottom of the fuselage, just behind the nosewheel. The aircraft, now resembling a double-barreled shotgun from the front, was ordered into production in 1955. Only five production aircraft had been completed before the entire program was canceled in early 1956 when the VVS discarded its close air-support doctrine in favor of tactical nuclear weapons on the battlefield. Development Sergey Ilyushin had begun design studies during 1950–51 for a jet-engined ground-attack ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ground-attack Aircraft
An attack aircraft, strike aircraft, or attack bomber is a tactical military aircraft that has a primary role of carrying out airstrikes with greater precision than bombers, and is prepared to encounter strong low-level air defenses while pressing the attack.Mortensen 1987, pp. 24–25. This class of aircraft is designed mostly for close air support and naval air-to-surface missions, overlapping the tactical bomber mission. Designs dedicated to non-naval roles are often known as ground-attack aircraft.Gunston 2009, p. 73. Fighter aircraft often carry out the attack role, although they would not be considered attack aircraft ''per se'', although fighter-bomber conversions of those same aircraft would be considered part of 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 Worl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Brake (aircraft)
In aeronautics, air brakes or speed brakes are a type of flight control surface used on an aircraft to increase the drag on the aircraft. Air brakes differ from spoilers in that air brakes are designed to increase drag while making little change to lift, whereas spoilers reduce the lift-to-drag ratio and require a higher angle of attack to maintain lift, resulting in a higher stall speed. Introduction An air brake is a part of an aircraft. When extended into the airstream, it causes an increase in the drag on the aircraft. When not in use, it conforms to the local streamlined profile of the aircraft in order to help minimise the drag. History In the early decades of powered flight, air brakes were flaps mounted on the wings. They were manually controlled by a lever in the cockpit, and mechanical linkages to the air brake. An early type of air brake, developed in 1931, was fitted to the aircraft wing support struts. In 1936, Hans Jacobs, who headed Nazi Germany's '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flash Suppressor
A flash suppressor, also known as a flash guard, flash eliminator, flash hider, or flash cone, is a muzzle device attached to the muzzle of a rifle that reduces its visible signature while firing by cooling or dispersing the burning gases that exit the muzzle, a phenomenon typical of carbine-length weapons. Its primary intent is to reduce the chances that the shooter will be blinded in low-light shooting conditions. Contrary to popular belief, it is only a minor secondary benefit if a flash suppressor reduces the intensity of the flash visible to the enemy. A flash suppressor is different from a muzzle brake, although they are typically mounted in the same position and sometimes confused with each other. While the former is intended to reduce visible flash, a muzzle brake is designed to reduce recoil inherent to large cartridges and typically does not reduce visible flash. Rationale Pre-20th century rifle designs tended to have longer barrels than modern rifles. A beneficial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muzzle Brake
A muzzle brake or recoil compensator is a device connected to, or a feature integral to the construction of, the muzzle or barrel of a firearm or cannon that is intended to redirect a portion of propellant gases to counter recoil and unwanted muzzle rise. Barrels with an integral muzzle brake are often said to be ported. The concept of a muzzle brake was first introduced for artillery. It was a common feature on many anti-tank guns, especially those mounted on tanks, in order to reduce the area needed to take up the strokes of recoil and kickback. They have been used in various forms for rifles and pistols to help control recoil and the rising of the barrel that normally occurs after firing. They are used on pistols for practical pistol competitions, and are usually called compensators in this context.STI article on Limcat Under ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flameout
In aviation, a flameout (or flame-out) is the run-down of a jet engine or other turbine engine due to the extinction of the flame in its combustor. The loss of flame can have a variety of causes, such as fuel starvation, excessive altitude, compressor stall, foreign object damage deriving from birds, hail, or volcanic ash, severe precipitation, mechanical failure, or very low ambient temperatures. Engine control Early jet engines were prone to flameout following disturbances of inlet airflow, or sudden or inappropriate thrust lever movements, which resulted in incorrect air-fuel ratios in the combustion chamber. Modern engines are much more robust in this respect, and are often digitally controlled, which allows for a significantly more effective control of all engine parameters to prevent flameouts and even initiate an automatic restart if a flameout occurs. Flameouts occur most frequently at intermediate or low power settings such as in cruise and descent. To prevent a flam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muzzle Flash
Muzzle flash is the light — both visible and infrared — created by a muzzle blast, which is caused by the sudden release and expansion of high-temperature, high-pressure gases from the muzzle of a firearm during shooting. Both the blast and flash are products of the exothermic combustion of the propellant (gunpowder), and any remaining unburned powders reacting with ambient air. The size and shape of the muzzle flash is dependent on the combustion energy of propellant being used, the amount of combustible ejecta remaining, and any devices attached to the muzzle (such as a flash hider, suppressor or muzzle shroud). Characteristics Muzzle flash can be broken down into five distinct components. *The ''muzzle glow'' is a reddish glow that is visible before the bullet leaves the barrel. It glow is created by superheated gases that have leaked past the projectile and have exited the barrel ahead of it. *The ''primary flash'' is caused by superheated propellant gases exiting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheelbase
In both road and rail vehicles, the wheelbase is the horizontal distance between the centers of the front and rear wheels. For road vehicles with more than two axles (e.g. some trucks), the wheelbase is the distance between the steering (front) axle and the centerpoint of the driving axle group. In the case of a tri-axle truck, the wheelbase would be the distance between the steering axle and a point midway between the two rear axles. Vehicles The wheelbase of a vehicle equals the distance between its front and rear wheels. At equilibrium, the total torque of the forces acting on a vehicle is zero. Therefore, the wheelbase is related to the force on each pair of tires by the following formula: :F_f = mg :F_r = mg where F_f is the force on the front tires, F_r is the force on the rear tires, L is the wheelbase, d_r is the distance from the center of mass (CM) to the rear wheels, d_f is the distance from the center of mass to the front wheels (d_f + d_r = L), m is the mass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxiing
Taxiing (rarely spelled taxying) is the movement of an aircraft on the ground, under its own power, in contrast to towing or pushback where the aircraft is moved by a tug. The aircraft usually moves on wheels, but the term also includes aircraft with skis or floats (for water-based travel). An airplane uses taxiways to taxi from one place on an airport to another; for example, when moving from a hangar to the runway. The term "taxiing" is not used for the accelerating run along a runway prior to takeoff, or the decelerating run immediately after landing, which are called the takeoff roll and landing rollout, respectively. Etymology As early as 1909 aviation journalists envisioned aeroplanes to replace the taxicab in traffic-congested cities. Some aviators and some linguists report that around the year 1911 the slang word "taxi" was in use for an "airplane". They suggest that the way aircraft move under power before they take off or after they land reminded someone of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Center Of Gravity Of An Aircraft
The center of gravity (CG) of an aircraft is the point over which the aircraft would balance. Its position is calculated after supporting the aircraft on at least two sets of weighing scales or load cells and noting the weight shown on each set of scales or load cells. The center of gravity affects the stability of the aircraft. To ensure the aircraft is safe to fly, the center of gravity must fall within specified limits established by the aircraft manufacturer. Terminology ;Ballast: Ballast is removable or permanently installed weight in an aircraft used to bring the center of gravity into the allowable range. ;Center-of-Gravity Limits: Center of gravity (CG) limits are specified longitudinal (forward and aft) and/or lateral (left and right) limits within which the aircraft's center of gravity must be located during flight. The CG limits are indicated in the airplane flight manual. The area between the limits is called the ''CG range'' of the aircraft. ;Weight and Balance: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drop Tank
In aviation, a drop tank (external tank, wing tank or belly tank) is used to describe auxiliary fuel tanks externally carried by aircraft. A drop tank is expendable and often capable of being jettisoned. External tanks are commonplace on modern military aircraft and occasionally found in civilian ones, although the latter are less likely to be discarded except in an emergency. Overview The primary disadvantage with drop tanks is that they impose a drag penalty on the aircraft. External fuel tanks will also increase the moment of inertia, thereby reducing roll rates for air maneuvers. Some of the drop tank's fuel is used to overcome the added drag and weight of the tank. Drag in this sense varies with the square of the aircraft's speed. The use of drop tanks also reduces the number of external hardpoints available for weapons, reduces the weapon-carrying capacity and increases the aircraft's radar signature. Usually the fuel in the drop tanks is consumed first, and only when a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bomb Bay
The bomb bay or weapons bay on some military aircraft is a compartment to carry bombs, usually in the aircraft's fuselage, with "bomb bay doors" which open at the bottom. The bomb bay doors are opened and the bombs are dropped when over the target or at a specified launching point. History and function Bomb bays were born of necessity. Early military aircraft suffered severe aerodynamic drag (which would further slow down the already lumbering bomb-laden aircraft) with bombs hanging from the wings or below the fuselage, so military aviation designers moved the bombs inside the aircraft. Before the introduction of stealth technology bomb bays were mostly used by dedicated bomber aircraft; in fighters and attack airplanes bombs and rockets were hung from the wings or fuselage on pylons. Notable exceptions are the F-101, F-102 and F-106 interceptor aircraft, all of which had bays used to store missiles, or other weapons stores. Today many designers have moved previously "e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barbette
Barbettes are several types of gun emplacement in terrestrial fortifications or on naval ships. In recent naval usage, a barbette is a protective circular armour support for a heavy gun turret. This evolved from earlier forms of gun protection that eventually led to the pre-dreadnought. The name ''barbette'' ultimately comes from fortification - it originally meant a raised platform or mound, as in the French phrase ''en barbette'', which refers to the practice of firing a cannon over a parapet rather than through an embrasure in a fortification's casemate. The former gives better angles of fire but less protection than the latter. The disappearing gun was a variation on the barbette gun; it consisted of a heavy gun on a carriage that would retract behind a parapet or into a gunpit for reloading. Barbettes were primarily used in coastal defences, but saw some use in a handful of warships, and some inland fortifications. The term is also used for certain aircraft gun mounts. Sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
