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64-401: The barrel roll is so named because an aircraft executing this maneuver looks as though it were flying with its wheels running around the inside wall of a cylinder, or an imaginary barrel lying on its side. A more common modern visualization is to imagine an airplane trying to fly in a horizontal corkscrew around the line of the direction of travel. Although the maneuver predates the name, the term

128-432: A barrel roll in the opposite direction. The attacker pulls back on the stick more than a normal barrel roll, performing a tighter loop than the roll. It is the three-dimensional equivalent of a 90-degree turn, and the attacker finishes the loop, having completed three quarters of a roll, with the nose pointed along the defender's flightpath. The maneuver is performed when an overshoot is imminent and cannot be corrected with

192-438: A "rollaway", uses the geometry of three dimensions by performing a half barrel-roll into the inverted position, then performing the second half of a loop with very little roll, keeping the lift vector aligned with the defender as the aircraft reverses direction. A canopy roll is the simplest form of displacement roll. The roll is used to provide lateral displacement while maintaining the original heading. The maneuver begins like

256-447: A barrel roll, resulting in a rolling scissors. A maneuver that greatly resembles a tight barrel-roll is the rudder roll. The rudder roll differs from the barrel roll both in that the application of back-stick pressure (elevator) is usually very high and that aileron input is held neutral throughout the maneuver. Instead, roll is produced by creating a sideslip through application of rudder combined with elevator. The aircraft will roll in

320-454: A broader set of piloting skills and exposes the aircraft to greater structural stress than for normal flight. In some countries, the pilot must wear a parachute when performing aerobatics. Aerobatic training enhances a pilot's ability to recover from unusual flight conditions, and thus is an element of many flight safety training programs for pilots. While many pilots fly aerobatics for recreation, some choose to fly in aerobatic competitions ,

384-540: A dogfight can be executed in an infinite number of geometric planes. Pilots are encouraged to keep their manoeuvres out of the strictly vertical and horizontal planes, but to instead use the limitless number of oblique planes, which is much harder for an adversary to track. This infinite number of planes around a fixed point about which the aircraft turns is termed the "post and bubble". A fighter that can maintain position between an aircraft and its imaginary post cannot be attacked by that aircraft. The imaginary bubble, however,

448-399: A fast moving attacker to slow his closing speed. An attacker is confronted with three possible ways to pursue an enemy, all of which are vital during chase. "Lag pursuit" happens in a turn when the nose of the attacker's aircraft points behind an enemy's tail. Lag pursuit allows an attacker to increase or maintain range without overshooting . "Lead pursuit" in a turn occurs when the nose of

512-492: A fully aerobatic helicopter, capable of performing loops and rolls, is the Westland Lynx . Most aerobatic manoeuvres involve rotation of the aircraft about its longitudinal (roll) axis or lateral (pitch) axis. Other maneuvers, such as a spin , displace the aircraft about its vertical (yaw) axis. Manoeuvres are often combined to form a complete aerobatic sequence for entertainment or competition. Aerobatic flying requires

576-416: A half aileron roll into the inverted position and beginning the barrel roll while upside-down. There are a variety of maneuvers that can be described as displacement rolls. A displacement roll is a barrel roll that moves the aircraft laterally, displacing it from its projected flightpath and moving it onto a new flightpath. Depending on how a displacement roll is executed, it may provide a shift laterally onto

640-420: A higher altitude than the opponent. Most of these rules are still as valuable today as they were a century ago. Today's air combat is much more complicated than that of older times, as air-to-air missiles , radar , and automatic cannons capable of high rates of fire are used on nearly all modern fighter aircraft. New and additional types of manoeuvres have emerged, intending to break radar lock by minimizing

704-473: A judged sport. In the early days of flying, some pilots used their aircraft as part of a flying circus to entertain. Maneuvers were flown for artistic reasons or to draw gasps from onlookers. In due course some of these maneuvers were found to allow aircraft to gain tactical advantage during aerial combat or dogfights between fighter aircraft. Aerobatic aircraft fall into two categories—specialist aerobatic, and aerobatic capable. Specialist designs such as

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768-410: A normal barrel roll, but when the plane is nearly inverted, the pilot places the elevators and ailerons close to the neutral position. Called "unloading", this allows the inverted aircraft to fly momentarily in a fairly straight arc. When the pilot has achieved enough lateral displacement, the pilot continues through the second half of the barrel roll. This type of roll is called a canopy roll because it

832-452: A normal displacement roll. Much more aggressive than a normal displacement roll, the maneuver begins by rolling slightly toward the direction of the defender's break, and then pulling up sharply. At roughly 30 degrees from the horizon, the pilot begins the barrel roll away from the defender's break, applying more elevator pressure than roll. When inverted, the pilot then uses the assistance provided by gravity combined with rudder control to bring

896-408: A parallel flightpath, or more aggressive rolls can be used to provide a reduction in turn radius . By moving the fighter more into the vertical plane, the pilot can use gravity to assist the aircraft in turn performance. In vertical or oblique geometric planes, the turn will be much slower over the top, and the turn radius will be much smaller. Conversely, the turn radius will be much larger through

960-449: A pilot will often make trade offs between the fighter's potential energy (altitude) and kinetic energy (airspeed), to maintain the energy-to-weight ratio of the aircraft, or the "specific energy". A manoeuvre such as the " low yo-yo " trades altitude for airspeed to close on an enemy and to decrease turn radius. The opposite manoeuvre, a " high yo-yo ", trades speed for height, literally storing energy in "the altitude bank", which allows

1024-404: A roll around a point on the horizon that is 45 degrees off the flightpath. Starting from a level flight, the pilot will usually pick such a point on the horizon as a reference, which is typically between the nose and the wing-tip, out the side window (if the plane has side windows). This point can be anything in that area, like a distant lake, mountain peak, or cloud. The pilot will then pull back on

1088-428: A rotation along the pitch axis (nose rotates upward, in a direction perpendicular to the wings) through the application of elevator input, followed by aileron input to rotate the aircraft along its roll axis. Sometimes rudder input is applied to help assist the roll through the yaw axis (nose rotates sideways), by swinging the tail over the top. At the midpoint (top) of the roll, the aircraft should be flying inverted, with

1152-497: A very hard turn, causing the wings to warp, performing the maneuver quite by accident, but was quickly followed by his companion flyer, David Wilke, who did two barrel rolls in a row; one to the left and the other to the right. Outside of aerobatic competition, the Boeing 367-80 and Concorde prototype were barrel-rolled during testing. The Boeing 367-80 was rolled twice by Tex Johnston in an unauthorized maneuver while demonstrating

1216-468: A wide variety of other terms, usually coined by air crew. This type of combat became known as dogfighting . Oswald Boelcke , a German fighter ace during World War I, was the first to publish the basic rules for aerial combat manoeuvring in 1916, known as the Dicta Boelcke . He advised pilots to attack from the direction of the sun (toward which the defending pilot could not see), or to fly at

1280-500: Is due to the ability to limit blood pooling for positive g maneuvers, but it is generally accepted that +9 g for more than a few seconds will lead to loss of consciousness (also known as GLOC ). Aerobatics are most likely to be seen at public airshows in the form of stunt flying. Aerobatic competitions usually do not attract large crowds of spectators since the manoeuvers are flown at safe altitudes to avoid accidents. Air combat maneuvering Air combat manoeuvring ( ACM )

1344-449: Is misshapen by gravity , causing turns to be much tighter and slower at the top, and wider and faster at the bottom, and is sometimes referred to as a "tactical egg". The manoeuvres employed by the attacker can also be used by the defender to evade, or gain a tactical advantage over his opponent. Other components may also be employed to manoeuvre the aircraft, such as yaw , drag , lift , and thrust vectors. A key factor in all battles

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1408-431: Is often used as a way for aircraft to quickly change positions, by rolling over the top of an airplane and coming down on the other side. Canopy rolls are often used in combat, to displace the attacker in relation to the defender's flightpath. An attacker following inside the defender's turn may need to displace the aircraft to the outside of the defender's turn in order to prevent an overshoot. Similarly, if following outside

1472-476: Is that the decisive factor does not lie in trick flying but solely in the personal ability and energy of the aviator. A flying man may be able to loop and do all the stunts imaginable and yet he may not succeed in shooting down a single enemy." Pilots soon learned to achieve a firing position (while avoiding the threat of enemy guns) by manoeuvring themselves behind an enemy aircraft; this is known as getting onto an aircraft's "six o'clock" or onto their "tail", plus

1536-733: Is the tactic of moving, turning, and situating one's fighter aircraft in order to attain a position from which an attack can be made on another aircraft. Commonly associated with dogfighting , air combat manoeuvres rely on offensive and defensive basic fighter manoeuvring (BFM) to gain an advantage over an aerial opponent. Military aviation originated in World War I when aircraft were initially used to spot enemy troop concentrations, field gun positions, and movements. Early aerial combat consisted of aviators shooting at one another with hand-held weapons. The first recorded aircraft to be shot down by another aircraft, which occurred on October 5, 1914,

1600-470: Is the practice of flying maneuvers involving aircraft attitudes that are not used in conventional passenger-carrying flights. The term is a portmanteau of "aeroplane" and "acrobatics". Aerobatics are performed in aeroplanes and gliders for training, recreation, entertainment, and sport. Additionally, some helicopters , such as the MBB Bo 105 , are capable of limited aerobatic manoeuvres . An example of

1664-427: Is then executed by applying excessive elevator pressure and hard rudder input during the barrel roll to assist with the roll. The sudden change in the relative forward speed may cause a surprised attacker to fly out in front of the defender. Depending on the situation, a high-g barrel roll can be performed "over the top", by beginning the roll like a normal barrel roll. The roll can also be performed "underneath", by doing

1728-403: Is usually an undesirable maneuver to be caught in, both for the attacker and the defender. The advantage usually goes to the aircraft with the higher turn rate, especially when pulling the nose through the top and bottom of the turns. Correct placement of the lift vector during the maneuver is crucial to keep from moving ahead, relative to the opponent. There are many optical illusions that affect

1792-404: Is usually behind the defender, to fly out in front, called overshooting . This can also help an attacker to prevent an overshoot. This often forces both planes to continue through a series of rolls known as a rolling scissors maneuver. A barrel roll is also often used to check blind spots while remaining on a steady flightpath. Rolling scissors, also called vertical scissors or simply "rollers",

1856-659: The Farnborough Airshow in September 1957. Aerobatics are taught to military fighter pilots as a means of developing flying skills and for tactical use in combat. Many aerobatic manoeuvres were indeed developed in military conflicts, e.g. the Immelmann turn or Split S . Aerobatics and formation flying is not limited solely to fixed-wing aircraft; the British Army , Royal Navy , Spanish Air Force and

1920-546: The Indian Air Force , among others, have helicopter display teams. All aerobatic manoeuvres demand training and practice to avoid accidents . Accidents due to aerobatic manoeuvres are very rare in competition aerobatics; most of them happen when performing formation flying or stunt flying at very low levels at airshows or air racing . Low-level aerobatics are extremely demanding and airshow pilots must demonstrate their ability before being allowed to gradually reduce

1984-940: The Pitts Special , the Extra 200 and 300 , and the Sukhoi Su-26 M and Sukhoi Su-29 aim for ultimate aerobatic performance. This comes at the expense of general purpose use such as touring, or ease of non aerobatic handling such as landing. At a more basic level, aerobatic capable aircraft, such as the Cessna 152 Aerobat or the R2160 Acrobin , can be dual purpose—equipped to carrying passengers and luggage, as well as being capable of basic aerobatic figures. Flight formation aerobatics are flown by teams of up to sixteen aircraft, although most teams fly between four and ten aircraft. Some are state funded to reflect pride in

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2048-412: The armed forces while others are commercially sponsored. Coloured smoke trails may be emitted to emphasise the patterns flown and/or the colours of a national flag. Aerobatic maneuvers flown in a jet-powered aircraft are limited in scope as they cannot take advantage of the gyroscopic forces that a propeller driven aircraft can exploit. Jet-powered aircraft also tend to fly much faster, which increases

2112-417: The fuselages of both aircraft into alignment. As the nose passes through the horizon, the pilot will then align the lift vector ahead of the defender, to bring the fighter back into the correct geometric plane, inside of the defender's turn. The success of a barrel roll attack depends greatly on the aircraft's ability to zoom climb . As the attacker is coming down, the defender may counter by pulling up into

2176-407: The specific energy of the aircraft. Position of aircraft must quickly be assessed, including direction, angle off tail (the angle between flight paths), and closing speed. Also, the pilot must be aware of his wingman 's position and maintain good communication. A pilot in combat attempts to conserve his aircraft's energy through carefully timed and executed manoeuvres. By using such manoeuvres,

2240-485: The Doppler signature of one's own aircraft ("keeping the enemy at 3 or 9 o'clock"), or to exhaust the kinetic energy of an incoming missile (by changing the aircraft's course from side to side, the missile, not flying directly at target but trying to forestall it, will make sharper turns and will eventually have to fly a longer path). However, close-range fighting with infrared guided missiles and aircraft cannons still obeys

2304-729: The Olympic games, and are governed by the FAI Aerobatics Commission (CIVA) Competitions start at Primary, or Graduate level (in UK "Beginners") and proceed in complexity through Sportsman (in UK "Standard"), Intermediate and Advanced, with Unlimited being the top competition level. Experienced aerobatic pilots have been measured to pull ±5 g for short periods while unlimited pilots can perform more extreme maneuvers and experience higher g levels -possibly up to +8/−6 g. The limits for positive g are higher than for negative g and this

2368-596: The aircraft to the International Air Transport Association over Lake Washington , Seattle. The Concorde was rolled multiple times by its test pilots, including Jean Franchi and Brian Walpole . Avro test pilot Roly Falk rolled the Avro Vulcan during a display at the 1955 Farnborough airshow, gaining height during the maneuver. To do a barrel roll in its purest form, from the pilot's perspective, it may best be thought of as

2432-434: The aircraft. Due to safety concerns, the smoke is not a result of combustion but is produced by the vaporization of fog oil into a fine aerosol , achieved either by injecting the oil into the hot engine exhaust or by the use of a dedicated device that can be fitted in any position on the aircraft. The first military aerobatic team to use smoke at will during displays was Fleet Air Arm 702 Squadron " The Black Cats " at

2496-471: The amount of energy needed to carry the slip all the way through the roll. It is generally more effective at combat speeds than a barrel roll due to the lowered effectiveness of aileron authority at higher speeds. The rudder roll is a basic maneuver used by air-to-air and surface-to-air missiles for providing in-flight course corrections, often giving them an erratic-looking flight path that oscillates around its target's track. Aerobatics Aerobatics

2560-484: The attacking aircraft points ahead of the enemy. Lead pursuit is used to decrease the distance between aircraft, and during gun attacks when the cannons must be aimed, not at where the defender is, but where he will be when the bullets get there. "Pure pursuit" happens when the nose of the attacker points directly at the defender. Pure pursuit is when most missiles will be fired, and is the hardest position to maintain. These are known as pursuit curves. The turning battle of

2624-406: The bottom of the turn, but the turn rate will be faster. Displacement rolls make full use of this assistance provided by gravity. By moving the fighter into more of the vertical plane, the pilot can then control the roll rate and yaw to provide a sharp reduction in turn radius, helping the attacker to prevent an overshoot and remain inside of the defender's turn. Such a displacement roll, also called

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2688-412: The direction of the rudder. This will cause the aircraft to sideslip through the roll, keeping the nose pointed at only a shallow angle from the flightpath. The aircraft will appear to slide almost sideways at a slight angle around a very narrow, helical path, more like an imaginary pipe than a barrel. The roll rate of a rudder roll is directly related to the angle of attack and mach number . The higher

2752-428: The film. A lag displacement roll , or "lag roll", helps improve the firing position of the attacking aircraft, and helps to increase range. The attacker performs the roll during a hard, turning chase, rolling both up and away from the turn. Typically performed a little slower than a normal displacement roll, the attacker achieves the proper reduction in turn radius on, or just outside the defender's turn. Upon completing

2816-432: The first pilot that attempts to disengage. A high-g barrel roll is a last-ditch defensive maneuver, performed when the attacker has achieved a suitable firing solution. The maneuver is performed when the attacker is very close, and a barrel roll performed by the defender may cause an overshoot. The maneuver begins by cutting the throttle, extending the speed brakes, or turning very hard to encourage an overshoot. The maneuver

2880-463: The height at which they may fly their show. In the EU, flying aerobatics requires special training and a rating. In Canada, no licence is required to perform aerobatics, but to carry passengers during aerobatics a pilot must have at least 10 hours dual flight instruction of aerobatic manoeuvres, or 20 hours of total aerobatic experience. Aerobatic flying competitions are a worldwide phenomenon, rather like

2944-416: The horizon as the nose traces a circle around this spot. Some planes may require rudder input, while most high powered planes will only need to be guided by aileron and elevator control. When the aircraft has rolled 90 degrees, and the wings are vertical, the nose should be angled about 45 degrees directly above the reference point. As the plane continues to roll upside-down it will begin to level out, and

3008-403: The horizon will appear to rise to meet the nose. When in the completely inverted position, the aircraft should be level and the nose should still be 45 degrees to the side of the reference point, putting it 90 degrees off the original flightpath. As the nose drops through the horizon, the pilot may need to reduce the elevator pressure, to avoid altitude loss by counteracting the force of gravity and

3072-422: The loss of lift. Still keeping the nose 45 degrees off the reference point, the plane should roll into level flight along the same flightpath and at the same altitude at which the maneuver began. If properly performed, the reference point should appear to remain in a fairly stationary position, relative to the plane, while the horizon spins around it. In air combat maneuvering , historically known as dogfighting ,

3136-448: The maneuver began. The term "barrel roll" is frequently used, incorrectly, to refer to any roll by an airplane (see aileron roll , slow roll or snap roll ). The barrel roll was originally called a "side somersault". It was first performed in 1905 by Daniel Maloney . He was flying a glider owned by John Joseph Montgomery during an exhibition show, which was lifted by balloon and then released. During this particular show, Maloney did

3200-474: The most effective armament for a majority of World War I era fighter planes, but it was nearly impossible to fire them through the spinning propeller of one's own aircraft without destroying one's own plane. Roland Garros , working with Morane Saulnier Aéroplanes , was the first to solve this problem by attaching steel deflector wedges to the propeller. He achieved three kills but was shot down by ground fire and landed behind German lines. Anthony Fokker inspected

3264-500: The most important. In Southeast Asia, over 85 percent of all kills are attributed to the attacker spotting and shooting the defender without ever being seen. Structural limitations of the attacking and defending fighters must be taken into account, such as thrust-to-weight ratio , wing loading , and the "corner speed" (the maximum or minimum speed at which the aircraft can attain the best turning performance). Variable limitations must also be considered, such as turn radius , turn rate and

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3328-423: The nose pointing at roughly a right angle to the general flightpath. The aircraft will have also gained altitude and travelled a short distance from the original flightpath. Flying inverted, the plane continues through the roll, descending in altitude and returning to the original flightpath. Upon completing the roll, the airplane should end up flying along the same flightpath, and at roughly the same altitude at which

3392-407: The pilot's ability to determine the relative position of the opponent, and mistakes can easily be made. It is extremely difficult to get a suitable firing solution during the rolling scissors. If the aircraft have a thrust-to-weight ratio of less than one, each consecutive roll will be lower than the previous, and the pilots can quickly find themselves at ground level. Any advantage is usually lost by

3456-624: The plane's wreckage and learned to improve the design by connecting the firing mechanism of the gun to the timing of the engine, thus allowing the gun to fire through the propeller without making contact with the propeller. As technology rapidly advanced, new and young aviators began defining the realm of air-to-air combat, such as Max Immelmann , Oswald Boelcke , and Lanoe Hawker . One of the greatest of these "ace pilots" of World War I, Manfred von Richthofen (the Red Baron), wrote in his book The Red Fighter Pilot , "The great thing in air fighting

3520-406: The roll, when the aircraft's lift vector points directly at the enemy, the pilot pulls back on the stick, reentering the turn with the ability to achieve a better firing position. A barrel roll attack is a military maneuver that improves the attacker's offensive position and prevents the attacker from overshooting. In this maneuver the defender breaks one direction and so the attacker performs

3584-464: The same general rules laid down in the skies over Europe in the early 20th century. The master rule is still the same: get on the opponent's rear without allowing them to do the same. Close-range combat tactics vary considerably according to the type of aircraft being used and the number of aircraft involved. There are five things a pilot must remain aware of when contemplating aerial engagement; of these, seeing and keeping sight of one's opponent are

3648-416: The size of the figures and the length of time the pilot has to withstand increased g-forces. Jet aerobatic teams often fly in formations, which further restricts the maneuvers that can be safely flown. Aerobatics done at low levels and for an audience is called "stunt flying". To enhance the show effect of aerobatic manoeuvres, smoke is sometimes generated; the smoke allows viewers to see the path travelled by

3712-447: The speed and the greater the angle of attack; the faster the roll will occur. The roll will tend to be more effective if the stick is pulled back until the point of buffet (the turbulence that precedes a stall), and often to the maximum that the elevators will allow. The rudder roll is typically more controllable than a barrel roll and can be performed at much higher roll-rates, but usually must be performed at very high speeds to produce

3776-408: The stick, bringing the plane up into a brief climb. As the nose passes through the horizon, the pilot begins to apply aileron input, which is accomplished by easing the stick to either the right or the left. As the airplane rolls it will continue to pitch in the direction of the lift vector . The pilot will need to carefully control the roll rate, keeping the nose 45 degrees off the reference point on

3840-417: The term "barrel roll" may refer to one of many maneuvers. These maneuvers are often simply called barrel rolls, but many fall into the category of "displacement rolls". The term barrel roll, by itself, most often refers to a helical roll around a straight flightpath, the purpose of which is to slow the relative forward motion (downrange travel) of the aircraft. This can help a defender to force an attacker, who

3904-417: The turn of a defender that is much more maneuverable, the attacker may be unable to pull the nose up into a suitable firing position. By using a canopy roll, the attacker can shift the aircraft laterally away from the defender's flightpath. This will cause the flightpaths of both airplanes to cross, using geometry to change the attacker's aim. Canopy rolls are often used by the attacker when the defender reverses

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3968-422: The turn, allowing the attacker to follow the reversal while keeping the correct relative position. The 1966 World War I-setting air combat film The Blue Max shows a canopy roll being performed by one of the pair of German Luftstreitkräfte pilots (the characters of Bruno Stachel and Willi von Klugermann), both flying Fokker Dr.I fighters, just before the tragic "daredevil" under-bridge flight sequence in

4032-497: Was a German Aviatik B.I . The pilot, Feldwebel Wilhelm Schlichting, was shot with a carbine wielded by observer Louis Quenault, who was riding in a French Voisin III piloted by Sergeant Joseph Frantz. The need to stop reconnaissance that was being conducted by enemy aircraft rapidly led to the development of fighter planes, a class of aircraft designed specifically to destroy other aircraft. Fixed, forward-firing guns were found to be

4096-465: Was first used in 1917, gaining popularity during the early 1930s. In aviation, the barrel roll is an aerobatic maneuver in which an aircraft performs a helical roll around its relative forward motion, with the nose ending up pointed along the original flightpath. It is performed by doing a combination of a roll and a loop. The maneuver includes a constant variation of aircraft attitude (nose orientation ) in two or perhaps all three axes. It consists of

#31968