Basic fighter maneuvers Basic fighter maneuvers ( BFM ) are tactical movements performed by fighter aircraft during air combat maneuvering ( also called ACM , or dogfight ing ) , in order to gain a positional advantage over the opponent . BFM combines the fundamentals of aerodynamic flight and the geometry of pursuit with the physics of managing the aircraft ' s energy - to - weight ratio , called its specific energy . Maneuvers are used to gain a better angular position in relation to the opponent . They can be offensive , to help an attacker get behind an enemy , or defensive , to help the defender evade an attacker ' s weapons . They can also be neutral , where both opponents strive for an offensive position , or disengagement maneuvers , to help facilitate an escape . Introduction . Basic fighter maneuvers are actions that a fighter aircraft makes during air combat maneuvering , historically known as dogfight ing . The development of BFM began with the first fighter aircraft , during World War I , then continued with each following war , adapting to the changing weapons and technologies . Basic fighter maneuvers consist of tactical turns , rolls , and other actions to get behind or above an enemy , before the opponent can do the same . BFM are typically universal maneuvers which can be performed in most any fighter aircraft , and are usually considered to be training maneuvers . Training usually begins with pilots flying the same type of aircraft , pitting only their skills against each other . In advanced training , pilots learn to fly against opponents in different types of aircraft , so pilots must learn to cope with different technological advantages as well , which more resembles real combat . In actual air combat maneuvering , variations of these basic maneuvers may become necessary , depending on the different types of aircraft involved , the weapon systems each side is using , and the number of aircraft involved . BFM are used in the three - dimensional arena of air combat , where maneuvers are not limited by simple two - dimensional turns , such as during a car chase . BFM not only relies on an aircraft ' s turn performance , but also on the pilot ' s ability to make trade - offs between airspeed ( kinetic energy ) and altitude ( potential energy ) to maintain an energy level that will allow the fighter to continue maneuvering efficiently . BFM also relies on the pilot ' s understanding of the geometry of pursuit within the three - dimensional arena , where different angles of approach can cause different rates of closure . The fighter pilot uses these angles not only to get within a range where weapons can be used , but also to avoid overshooting , which consists either of flying out in front of the opponent , called a " wingline overshoot " , or crossing the enemy ' s flightpath , called a " flightpath overshoot " . The fighter pilot with the most advantageous position is usually above or behind the opponent , and is commonly called the attacker . Conversely , the pilot in the disadvantageous position is usually either below or ahead of the opponent , and is referred to as the defender . Most maneuvers are offensive , such as the " barrel roll attack " , " high Yo - Yo " , " low Yo - Yo " , and " lag roll " . Defensive maneuvers more often consist of turning very aggressively to avoid the attacker ' s guns , with maneuvers like the " break " and the " high Yo - Yo defense " ; sometimes tightening the turn , sometimes relaxing it , and other times reversing the turn . The defender will usually maneuver to force an overshoot , or to extend the range enough to dive away and escape . However , other " last - ditch " maneuvers are used by the defender when the attacker achieves a firing solution , or the defender ' s energy becomes depleted so that maximum turn performance cannot be maintained , such as " guns defense " or the " defensive spiral " . History . Basic fighter maneuver development began during World War I , with maneuvers such as the " Immelmann " , named after German pilot Max Immelmann , the " break " , and the " barrel roll " . However , the modern Immelmann differs from the original version , which is now called a stall turn or " Hammerhead turn " . The original Immelmann was an effective maneuver in the early part of the war , but as aircraft technology advanced , and fighter engines became increasingly more powerful , it became a dangerous maneuver , because the opponent could climb and shoot the German fighters when they were almost motionless at the top of the turn . " Billy Bishop , the top Canadian ace of World War I , described a break : " Watching carefully over your shoulder and judging the moment he will open fire , you turn your machine quickly so as to fly at right angles to him . His bullets will generally pass behind you during the maneuver " . During World War I , due to the low power of early aircraft , the most common type of engagement was known as a Lufbery , which consisted of two fighters chasing each other around the same circle , often 180 degrees apart . This type of engagement , however , is energy - depleting , causing the fighters to lose altitude until they run out of maneuvering room . This type of fight became a game of chicken , forcing one fighter to attempt an escape before crashing into the ground , and giving the advantage to the other . As engines became more powerful , three - dimensional tactics became available to counter the stalemate of the Lufbery , allowing fighters to maneuver onto the tail of their opponents . Development continued through each consecutive war , as aircraft and weapon systems became increasingly more advanced . Maneuvers such as the " combat spread " were first devised by pilots like Werner Molders during the Spanish civil war , while the energy - managing maneuvers called the " high and low Yo - Yos " were credited to a Chinese pilot named Yo - Yo Noritake , during World War II . A simple , non - turning form of the low - Yo - Yo is depicted in John Godfrey ' s description of his first kill , flying a Republic P - 47 Thunderbolt over Europe during World War II : " Breathlessly I watched the 109 in between the breaks in the clouds as I dove . At 12 , 000 feet I leveled off and watched him up ahead . In diving I had picked up speed , and now had hit 550 miles an hour . I was about 500 feet below him and closing fast . " Quick now , I ' ve got time . " I checked all around , in back and above me , to ensure that no other [ Germans ] were doing the same to me . My speed was slacking off now , but I still had enough to pick up that extra 500 feet and position myself 200 yards dead astern . The 109 flew as straight as an arrow , with no weaving . As his plane filled my gunsight , I pressed the [ trigger ] " . However , much of the modern energy - management techniques , which are used in maneuvers like the Yo - Yos , were only described scientifically after John R . Boyd developed his Energy - Maneuverability theory during the Vietnam War . Even so , as quoted by the U . S Navy Air Training Command , " 1 ) The basics of ACM have not changed since the early days of aviation , and 2 ) A fighter pilot must maintain constant aggressiveness for success . As the [ Red ] Baron would say , ' All else is rubbish . ' " Training . Basic fighter maneuvers ( BFM ) are used by fighter pilots during a dogfight to gain a positional advantage over an opponent . Pilots must have keen knowledge of not only their own aircraft ' s performance characteristics , but also of the opponents , taking advantage of their own strengths while exploiting the enemy ' s weaknesses . Pilots need good eyesight , situation awareness , and the ability to maneuver against an opponent in three dimensions . BFM are generally grouped into two categories : Primary maneuvers are those which are performed without respect to an enemy ' s position . These are often simple maneuvers , such as climbs , turns and rolls . Relative maneuvers are performed in relation to the motion of another aircraft . These are often more complex , including energy saving maneuvers , such as the high and low Yo - Yos , and repositioning maneuvers such as displacement rolls . It is easy to fall into the trap of considering BFM to be a series of set maneuvers providing a foolproof recipe for a dominant position . The reality is that BFM are a series of fluid and often improvised proactive and reactive actions , varying infinitely according to range , altitude , speed , aircraft type , weapons system type and any of an enormous range of other factors . An extremely successful tactic one day may yield unfortunate results if repeated the next day , and pilots often credit luck as a major factor . BFM are normally considered to be individual maneuvers , where ACM is applied to the tactics behind dogfight ing as a whole . In military training , BFM are often conducted against an adversary in the same type of aircraft . This allows the pilot to fly against a machine with known performance values and allows aircrew to build their awareness of important concepts such as sight picture , rates of closure and line of sight rates that are cues to being successful in the visual arena . This also allows pilots to build their BFM skills against one another , without either having a particular technological advantage . Dissimilar air combat maneuvers are advanced maneuvers performed by aircraft of two separate types ( such as F - 16 vs F / A - 18 ) . This training is valuable in that both pilots are not as aware of the performance capabilities and characteristics of the other aircraft and , therefore , must rely on the fundamental BFM principles and evaluation / decision making skills to maneuver to an advantageous position versus their opponent . In this type of training , the advantages of one type of fighter may differ greatly from the advantages of the other , so pilots learn to refine their BFM skills to make use of the opponent ' s weaknesses . Using BFM as the building blocks for multiple aircraft maneuvers , such as the finger four , loose deuce , and Thach weave , pilots learn how to maneuver in situations involving one against one , one against two , or even one against many . This type of training , introduced during the last stages of flight school , is more like actual combat , and is the most beneficial for aircrew once basic BFM skills are mastered . BFM principles . Specific energy . Energy is a primary factor in controlling and maneuvering an aircraft . If an attacker has too much energy , it may be easy to get in range but difficult to prevent an overshoot . Too little energy and the attacker may not be able to get in range at all . If the defender has more energy than the attacker , an escape may be possible , but too little energy and the defender will lose maneuverability . In aviation , the term " energy " does not refer to the fuel nor the thrust it produces . Instead , thrust is referred to as " power . " Energy is the state of the fighter ' s mass at any given time , and is the result of the power . Energy comes in two forms , which are kinetic and potential . Kinetic energy is a function of the fighter ' s mass and speed , while potential energy is a function of its mass , gravity and altitude . The combined potential and kinetic energy is called the total energy , or " energy package . " Because the energy package is the combination of mass , speed and altitude , a fighter flying at low altitude but a high speed may have the same total energy as a fighter of equal mass , but flying at a low speed and high altitude . Generally , the fighter that is able to maintain a higher energy package will have the advantage . However , a high energy - package alone does not improve maneuverability , because optimum turn performance typically occurs within a range near a certain speed , called the " corner speed . " Also , increasing the mass of the aircraft would increase its energy package , but centrifugal force would hamper maneuverability , causing the heavier aircraft to turn wider circles . Instead , the fighter ' s useful energy is calculated by dividing its energy package by its weight , determining its specific energy ( total energy per unit - weight ) . A fighter with less mass will generally be more maneuverable than a fighter with more mass , even if energy packages are equal , because the lighter aircraft has more specific - energy . " Specific power , " on the other hand , is the thrust divided by weight , and the fighter ' s ability to generate excess specific - power aids the craft in maintaining its specific energy longer when forced to turn at an energy - depleting rate . Typically , the fighter with higher energy ( energy fighter ) will make an " energy move " like an " out - of - plane maneuver , " to maintain the energy - advantage , while the fighter at an energy - disadvantage ( angles fighter ) will make an " angles move " such as a break turn , trying to use the opponent ' s energy to their own advantage . Energy management . In combat , a pilot is faced with a variety of limiting factors . Some limitations are constant , such as gravity , structural integrity , and thrust - to - weight ratio . Other limitations vary with speed and altitude , such as turn radius , turn rate , and the specific energy of the aircraft . The fighter pilot uses BFM to turn these limitations into tactical advantages . A faster , heavier aircraft may not be able to evade a more maneuverable aircraft in a turning battle , but can often choose to break off the fight and escape by diving or using its thrust to provide a speed advantage . A lighter , more maneuverable aircraft can not usually choose to escape , but must use its smaller turning radius at higher speeds to evade the attacker ' s guns , and to try to circle around behind the attacker . BFM are a constant series of trade - offs between these limitations to conserve the specific energy state of the aircraft . Even if there is no great difference between the energy states of combating aircraft , there will be as soon as the attacker accelerates to catch up with the defender . However , potential energy can easily be traded for kinetic energy , so an aircraft with an altitude advantage can easily turn the potential energy into speed . Instead of applying thrust , a pilot may use gravity to provide a sudden increase in speed , by diving , at a cost in the potential energy that was stored in the form of altitude . Similarly , by climbing the pilot can use gravity to provide a decrease in speed , conserving the aircraft ' s kinetic energy by changing it into altitude . This can help an attacker to prevent an overshoot , while keeping the energy available in case one does occur . Turn performance . Both turn rate , ( degrees per second ) , and turn radius , ( diameter of the turn ) , increase with speed , until the " corner speed " is reached . At this point , the growing turn radius begins to decrease the turn rate , so the aircraft will reach its best turn performance at its particular corner speed . Corner speed is defined as the minimum speed at which the maximum sustainable g - force load can be generated ( the load at which power equals drag ) , and varies with the fighter ' s structural design , weight ( including added weight from missiles , drop - tanks , etc . . . ) , and thrust capabilities . It often falls in the area of . The maximum sustainable - load the aircraft can generate also varies , but is typically between 3 to 5 g ' s . At the corner speed , the fighter can attain its maximum turn - rate , flying the craft just at the edge of buffeting ( the turbulence preceding a stall ) . Below this speed , the aircraft will be limited to flying at lower g ' s , resulting in a decrease in turn rate . If the pilot attempts to " pull " more g ' s , the aircraft will buffet and aerodynamically stall . On the other hand , if the fighter is flown above its corner speed it will be able to pull higher g ' s , but doing so will cause it to lose airspeed from the excess drag created . Turning above corner speed while at the maximum sustainable - load will result in an increase in turn radius which , respectively , will cause a decrease in turn rate . " Instantaneous turn - rate " describes turns which are above the maximum sustainable - load . These turns can be as high as 9 g ' s before the pilot begins to lose consciousness ( G - LOC ) . These turns can have a very small turn radius , but cause a loss in energy , either in the form of speed or altitude . Therefore , these turns are unsustainable , causing the fighter to lose massive amounts of airspeed , sometimes reaching stall speed in as little as a quarter turn . To some degree the energy loss may be compensated for by increasing thrust , known as applying " excess specific power , " but this cannot fully make up for the losses . This usually occurs during hard turns or even harder " breaks . " Only by turning the aircraft at its best " sustained turn - rate " can the aircraft maintain its specific energy . However , situations in combat may require a change in energy , and energy may also be increased by pulling less than the maximum sustained g - force load . Pursuit curves . Successful BFM requires geometry as much as it does skill and stamina . Pilots must know their aircraft ' s corner speed , as well as optimum angles of bank ( AOB ) and angles of attack ( AOA ) , without consciously thinking about them . At the same time , pilots must remain conscious of the angle between the opponent ' s velocity vector and their own , called the track crossing angle ( TCA ) , which is important when aligning or avoiding a firing solution . Most importantly , the pilot must remain aware of the angle off tail ( AOT ) , which is the angle between flightpaths . A high AOT causes a high rate of closure , but makes achieving a suitable guns solution nearly impossible . Acquiring a low AOT , ( getting on the enemies tail ) , can decrease or even reverse closure rate , and is usually the primary goal before an overshoot occurs . However , an uncooperative defender may try to take advantage of the high closure rate by turning to increase AOT , forcing an overshoot . The AOT is often estimated by the position of the attacking aircraft ' s nose in relation to the defender . AOT are generally grouped into three categories , called " pursuit curves " . " Lead pursuit " occurs when the nose of the attacker points ahead of the defender , while " pure pursuit " happens when the attacker ' s nose points directly at the defender . If the attacker ' s nose points behind the defender , the condition is known as " lag pursuit " . Lead pursuit . The primary purpose for lead pursuit is to provide closure , even when chasing a faster opponent . The high AOT presented during lead pursuit allows the attacker to quickly decrease the forward , lateral , and vertical separation between aircraft , simply by traveling a shorter path . However , lead pursuit causes the AOT to increase at a rapid rate . This causes the closure rate to increase as well , and , in an attempt to prevent an overshoot , the attacker will have to pull an increasingly tighter turn upon nearing the defender . An attacker in lead pursuit is well within the defender ' s rear view . Unless the defender has enough of a speed advantage to escape by relaxing the turn and dropping into a shallow dive , the defender will likely turn sharply in an effort to increase the AOT , forcing the attacker to turn even harder , to overshoot , or to perform a maneuver out of the horizontal plane to compensate . Lead pursuit is used during gun attacks , because the fast motion of combat requires that the aircraft ' s cannons be aimed at a point in space ahead of the defender , where the enemy will be when the bullets arrive . This is called " leading the target " . Lead pursuit presents the attacker with difficulty in maintaining sight of the opponent , as the nose of the attacking aircraft becomes an obstruction to the pilot ' s view . Pure pursuit . Like lead pursuit , pure pursuit is used to provide closure . However , closure is not as rapid , nor is the rate of increase in AOT . This is not as effective against a faster moving opponent , so the attacker may need to accelerate to maintain pure pursuit . Pure pursuit is used when acquiring a missile lock . It both places the attacker further aft of the defender and presents the defender with the smallest amount of surface area to see . This complicates evasive action , since only the front of the attacking aircraft is in view . Lag pursuit . Lag pursuit is used to stop or reverse closure rate and to decrease AOT , while allowing the attacker to maintain or increase forward separation ( also called nose / tail separation , or nose - to - tail ) . Following outside the defender ' s turn radius , the attacker can maintain or increase energy while forcing the defender to turn at an energy depleting rate . " Hot side " lag occurs when there is a large amount of forward separation between aircraft , showing the top side of the defending fighter . This puts the attacker in the defender ' s rear view , and the common defense is to tighten the turn . " Cold side " lag occurs when there is little nose - to - tail separation , leaving the belly of the defending fighter in view . This puts the attacker in the defender ' s blind spot , and the common defense is to reverse the turn . Unless the defender is markedly more maneuverable , and lateral separation is just right , lag pursuit can not be maintained for long , causing the AOT to decrease until a suitable firing solution is presented . Out - of - plane maneuvers . Maneuvers are rarely performed in the strictly vertical or horizontal planes . Most turns contain some degree of " pitch " or " slice . " During a turn in an oblique plane , a pitch turn occurs when the aircraft ' s nose points above the horizon , causing an increase in altitude . A slice turn happens when the nose points below the horizon , causing a decrease in altitude . The purpose is not only to make the aircraft harder for an enemy to track , but also to increase or decrease speed while maintaining energy . An out - of - plane maneuver enhances this effect , by diverting the fighter into a new plane of travel . Increasing the pitch or slice can quickly provide a change in speed , which can just as quickly be reversed by returning to the original plane of travel . Out - of - plane maneuvers are not only used to provide a reduction in turn radius , but also causes the fighter to fly a longer path in relation to the direction of travel . A maneuver such as a high Yo - Yo is used to slow closure and to bring the fighter into lag pursuit , while a low Yo - Yo is used to increase closure and to bring the fighter into lead pursuit . During an out - of - plane maneuver , the attacker ' s nose no longer points at the defender . Instead , the aircraft is rolled until its lift vector , ( an imaginary line running vertically from the center of the aircraft , perpendicular to its wings ) , is aligned either ahead of , directly at , or behind the defender , using roll rate instead of turn rate to set the proper pursuit curve . The aircraft ' s velocity vector , ( an imaginary line in the direction of motion ) will be pulled in the direction of the lift vector . Displacement rolls . A useful type of out - of - plane maneuver employed to decrease AOT are various barrel roll s called displacement rolls , in order to shift the aircraft laterally from its projected flight path onto a new flight path . By controlling the roll rate the pilot can control the degree of displacement . An attacker following a more maneuverable opponent may become stuck in lag pursuit , ( outside the defender ' s turn radius ) , unable to achieve a firing solution . By displacing the turn , the two aircraft ' s flight paths will eventually cross . The AOT will then decrease until the nose of the attacker ' s aircraft points momentarily at the defender , and then ahead of the defender . A displacement roll is a good tactic when ever a reduction in turn radius is needed , but a decrease in turn rate is allowed . Positioning . There are three basic situations in air combat maneuvering requiring BFM to convert to a favorable result , which are neutral , offensive , and defensive . Most relative maneuvers can be grouped into one of these three categories . Neutral . Neutral positions generally occur when both opponents spot each other at the same time . Neither the pilot nor the opponent have the advantage of surprise . Neither has the ability to point the nose of their aircraft at the opponent with sufficient range to employ forward firing ordnance ( missiles / guns ) prior to the opponent presenting a threat of a similar manner . Each is focused on converting to an offensive situation while forcing their opponent into a defensive . Offensive . An offensive position generally occurs when the pilot gets sight of the opponent first . With the advantage of surprise , the pilot can maneuver into a better position to attack the opponent , making it more difficult for the enemy to evade the attack . Common tactics include increasing altitude and attempting to place the fighter directly between the sun and the opponent . This helps put the pilot in a dominant position , primarily concerned with prosecuting their advantage for a kill . An offensive position is generally defined as the ability to get above or behind the enemy . The pilot is able to create an energy advantage , providing the ability to swoop down on the opponent and spray the area with bullets while using the speed to climb back to a safe altitude . The attacker also has an orientation - related advantage , being able to press the attack while avoiding the enemy ' s weapons . Defensive . A defensive position usually occurs when the pilot spots the attacker late . Usually below or ahead of the opponent , the pilot is in a weak position , primarily concerned with denying a shot to the opponent and converting to a neutral position . The secondary goal is either to escape or to achieve a dominant position . If the attacker is at an energy disadvantage , the defender will likely use the speed to disengage , but , if the attacker is moving much faster , the defender will usually maneuver in order to force a dangerous overshoot . A dangerous overshoot happens when an attacker flies out in front of the defender , causing their roles to be reversed . BFM concepts . Once an attacker gets behind a defender , there are three problems to solve in order to prosecute the kill . The attacker must be able to get into the same geometric plane as the defender , get in range without overshooting , and be able to lead the target . The defender will usually turn aggressively to spoil the attacker ' s solution . Turn circle . Aircraft turn in circular motions , following a circumference around a central point . The circumference is often referred to as the " bubble , " while the central point is often called the " post . " Any change in the g - force load on the aircraft causes a change in the bubble ' s size as well as a change in turn radius , moving the post in relation to the fighter . Because an aircraft turning at its maximum load cannot turn any tighter , any aircraft located between such a fighter and its post is momentarily safe from attack . It is in this area where an attacking fighter will usually try to position itself . Once inside the defender ' s bubble , the attacker will be in lead pursuit and may have an opportunity for a lucky " snapshot " hit . If the attacker can maneuver onto the defender ' s flight path before an overshoot occurs , the attacker will be able to stop or reverse closure rate . The most desirable position is , following the defender ' s flight path , a distance equal to one turn radius behind the opponent . This position , from which the attacker will be able to safely maintain command of the fight , is termed the " control point . " The control point lies in the heart of an imaginary , cone - shaped area , called the " control zone , " and it is within this zone that the attacker will have both sufficient time and range to react to the defender ' s countermeasures . Overshoots . During a dogfight , the term " overshoot " refers to situations in which the attacker either crosses the enemy ' s flightpath or passes the defender , ending up in front . Passing the defender is referred to as a " wingline overshoot " . Also called a " 3 - 9 line overshoot " or a " dangerous overshoot , " this occurs when an attacking aircraft approaches too fast and accidentally crosses the defender ' s wingline , ( an imaginary line passing through the center of the aircraft at the 3 o - clock and 9 o - clock positions ) . A wingline overshoot is usually referred to as " flying out in front " and causes " role reversal , " putting the attacker in range of the defender ' s weapons , and the attacker suddenly becomes the defender . When the attacker crosses the defender ' s flightpath , the situation is called a " flightpath overshoot . " This happens when an attacker fails to control closure and crosses the defender ' s flightpath from behind . Although not necessarily dangerous , it is possible for a flightpath overshoot to cause the attacker to fly out in front of the defender . More often , however , it greatly reduces the attacker ' s angular advantage over the defender . Flightpath overshoots are divided into two categories , called " control - zone overshoots " and " in - close overshoots . " A " control - zone overshoot " occurs when the attacker crosses the defender ' s flightpath from behind the front edge of the control zone . After a control - zone overshoot , the defender will continue turning in the same direction to retain the acquired angular advantage , trying to prevent the attacker from getting a good aim . An ' " in - close overshoot " happens when the attacker overshoots the defender ' s flightpath ahead of the control zone . This gives the defender the opportunity to reverse the turn and possibly to cause a wingline overshoot , allowing the defender to move in behind the attacker and reverse their roles . Circle flow . Aircraft can turn either towards or away from each other . How the opponent turns in relation to the other determines the flow of the fight . If two fighters meet head - on , they will usually make a very close , neutral pass , called a " merge " . After the pass , both fighters may turn to engage . If the two fighters turn in the same direction , ( i . e . : both turn to the north ) , they will be traveling toward each other along the same turn circle . This type of engagement is known as " one - circle flow " . If the aircraft turn in opposite directions , ( i . e . : one turns north but the other turns south ) , they will move away from each other , flying around to engage each other on separate turn circles . This is called " two - circle flow . " One - circle flow will result in another merge , unless an angular advantage can be obtained . During one - circle flow , the fighter with the smaller turn radius will have the advantage . Pilots will often pitch - up out - of - plane while increasing thrust , to help minimize turn radius . Because it does not really matter where the two fighters meet in the circle , turn rate is of little importance during one circle flow . Therefore , it is often called a radius fight . An out - of - plane maneuver , such as a displacement roll , is a viable option for reducing turn radius . Two - circle flow will also result in another merge . In two - circle flow , turn radius is of little importance , because what matters is which fighter can get back to the merging place first . Two - circle flow is a turn rate fight , and the angular advantage usually goes to the aircraft with the higher turn rate at its corner speed . Pilots will often slice turn in order to maximize their turn rate . A third option is called vertical flow , in which one or both fighters turn toward the vertical plane . If both fighters go up or down , the fight becomes one - circle flow . If one fighter goes up or down , while the other turns horizontally , it is really a modified version of one - circle flow . However , if one fighter goes up while the other goes down , it becomes two - circle flow . In both types of flow , the closest possible merge is desirable to keep the enemy at an angular disadvantage . Although circle flow is often described using neutral merges , the concept applies anytime two aircraft maneuver in relation to each other and the horizon . For instance , the " flat scissors " is an example of one - circle flow , while the " rolling scissors " is an example of two - circle flow . Maneuvers . Combat spread . The combat spread is the most basic of maneuvers used prior to engagement . A pair of attacking aircraft will separate , often by a distance of one mile horizontal by 1500 feet vertical . The fighter with the lower altitude becomes the defender , while the wingman flies above in " the perch " position . The defender will then attempt to lure their opponents into a good position to be attacked by the wingman . Defensive split . A pair of fighters encountering one or two attackers will often use a defensive split . The maneuver consists of both defenders making turns in opposite directions , forcing the attackers to follow only one aircraft . This allows the other defender to circle around , and maneuver behind the attackers . Break . Spotting an attacker approaching from behind , the defender will usually break . The maneuver consists of turning sharply across the attacker ' s flight path , to increase AOT ( angle off tail ) . The defender is exposed to the attacker ' s guns for only a brief instant ( snapshot ) . The maneuver works well because the slower moving defender has a smaller turn radius and bigger angular velocity , and a target with a high crossing speed ( where the bearing to the target is changing rapidly ) is very difficult to shoot . This can also help to force the attacker to overshoot , which may not be true had the turn been made away from the attacker ' s flight path . Barrel roll attack . The counter to a break is often a displacement roll called a barrel roll attack . A barrel roll consists of performing a roll and a loop , completing both at the same time . The result is a helical roll around a straight flight path . The barrel roll attack uses a much tighter loop than the roll , completing a full loop while only executing 3 / 4 of a roll . The result is a virtual 90 degree turn , using all three dimensions , in the direction opposite of the roll . Rolling away from the defender ' s break , the attacker completes the roll with the aircraft ' s nose pointed in the direction of the defender ' s travel . High - side guns pass . If the attacker has a significant altitude advantage , a high - side guns pass is usually prudent . Sometimes called a " swoop " , plus a variety of other names , it consists of a powered dive toward the rear quarter of a lower flying opponent . Shooting with the cannons in a single , high - speed pass , the attacker uses excess kinetic energy to disengage from the fight in a zoom climb back to a safe altitude , restoring the potential energy . This allows the attacker to set up another attack and dive again . Surprise is often a key element in this type of attack , and the attackers will often hide in the sun or clouds , stalking their opponents until a good opportunity is presented . A high - side guns pass is a very effective tactic against a more maneuverable opponent , where the turning battle of a dogfight is best avoided . Immelmann . An Immelmann trades airspeed for altitude during a 180 degree change in direction . The aircraft performs the first half of a loop , and when completely inverted , rolls to the upright position . The Immelmann is a good offensive maneuver for setting up a high - side guns pass against a lower altitude , slow moving opponent , going in an opposite direction . However , an Immelmann is a poor defensive maneuver , turning the defender into a slow moving target . Split - s . The opposite of an Immelmann is the Split - S . This maneuver consists of rolling inverted and pulling back on the stick , diving the aircraft into a half loop , which changes the aircraft ' s direction 180 degrees . The split - s is rarely a viable option in combat as it depletes kinetic energy in a turn and potential energy in a dive . It is most often used to set up a high - side guns pass against a lower but fast moving opponent that is traveling in the opposite direction . Also , the split - s is sometimes used as a disengagement tactic . Pitchback . A pitchback , also called a Chandelle , is an Immelmann that is executed in some plane other than the vertical . Basically just a pitch turn , the fighter will be at some angle of bank before performing the half loop and roll . Unlike the Immelmann , a pitchback depletes less kinetic energy and is harder for an adversary to track . Wingover . A wingover is a maneuver used to provide a fast , 180 degree turn with a very small turn radius . It consists of a quarter loop into a vertical climb , letting the speed fall as altitude increases , and then a flat - turn over the top , diving to complete a quarter loop at the original altitude , but going in the opposite direction . The wingover is similar to a stall turn , but the fighter does not actually stall , which makes the wingover more difficult for an enemy to track . Unlike an Immelmann or a split - s , the wingover also manages energy by conserving both airspeed and altitude . Low Yo - Yo . The low Yo - Yo is one of the most useful maneuvers , which sacrifices altitude for an instantaneous increase in speed . This maneuver is accomplished by rolling with the nose low into the turn , and dropping into a steeper slice turn . By utilizing some energy that was stored in the vertical plane , the attacker can quickly decrease range and improve the angle of the attack , literally cutting the corner on the opponent ' s turn . The pilot then pulls back on the stick , climbing back to the defender ' s height . This helps slow the aircraft and prevents an overshoot , while placing the energy back into altitude . A defender spotting this maneuver may try to take advantage of the increase in AOT by tightening the turn in order to force an overshoot . The low Yo - Yo is often followed by a high Yo - Yo , to help prevent an overshoot , or several small low Yo - Yos can be used instead of one large maneuver . High Yo - Yo . The high Yo - Yo is a very effective maneuver , and very difficult to counter . The maneuver is used to slow the approach of a fast moving attacker while conserving the airspeed energy . The maneuver is performed by reducing the angle at which the aircraft is banking during a turn , and pulling back on the stick , bringing the fighter up into a new plane of travel . The attacker then rolls into a steeper pitch turn , climbing above the defender . The trade - off between airspeed and altitude provides the fighter with a burst of increased maneuverability . This allows the attacker to make a smaller turn , correcting an overshoot , and to pull in behind the defender . Then , by returning to the defenders plane , the attacker restores the lost speed while maintaining energy . Lag displacement roll . A lag displacement roll , also called a " lag roll " , is a maneuver used to reduce the angle off tail by bringing the attacker from lead pursuit to pure , or even lag pursuit . The maneuver is performed by rolling up and away from the turn , then , when the aircraft ' s lift vector is aligned with the defender , pulling back on the stick , bringing the fighter back into the turn . This maneuver helps prevent an overshoot caused by the high AOT of lead pursuit , and can also be used to increase the distance between aircraft . High Yo - Yo defense . To prevent an overshoot , an attacker in lead pursuit may need to correct with an out - of - plane maneuver . If the lateral separation is excessively high , the attacker will probably use a displacement roll . However , if the lateral separation is low enough , the attacker will likely use a high Yo - Yo . The high Yo - Yo defense can be a good tactic in these situations . The maneuver is performed when the attacker rolls away from the turn to begin the correction . The defender will begin to relax the turn by easing off of the stick , called " unloading " , which causes both turn radius and speed to increase , restoring the fighter ' s lost energy . If the defender maintains the same angle of bank , the subtle maneuver will be very difficult for the attacker to spot . When the attacker completes the out - of - plane maneuver , the defending fighter has regained some of its energy . This allows the defender to , once again , turn harder into the attack , regaining an angular advantage over the higher energy attacker . If the attacker is surprised by the maneuver , a high Yo - Yo defense might even cause an overshoot . Unloaded extension . An unloaded extension is a disengagement ( bug out ) maneuver often used by the pilot whenever there is enough energy and separation . The maneuver consists of slipping into a steep , straight dive and applying full thrust . Removing all g - force load from the aircraft causes it to accelerate at a very high rate , allowing the pilot to vastly increase range , or " extend " , and possibly to escape . If a defender breaks suddenly , causing the attacker to overshoot , the defender may reverse the turn and move in behind the attacker . An unloaded extension is usually the attacker ' s best option , using the energy advantage to escape the slower moving defender . An unloaded extension is usually not recommended against a higher energy opponent . However , in many circumstances , such as when an attacker performs a high Yo - Yo too steeply , an unloaded extension is a viable option for the defender . Scissors . The scissors are a series of turn reversals and flightpath overshoots intended to slow the relative forward motion ( downrange travel ) of the aircraft in an attempt to either force a dangerous overshoot , on the part of the defender , or prevent a dangerous overshoot on the attacker ' s part . The defender ' s goal is to stay out of phase with the attacker , trying to prevent a guns solution , while the attacker tries to get in phase with the defender . The advantage usually goes to the more maneuverable aircraft . There are two types of scissor maneuvers , called flat scissors and rolling scissors . Flat scissors . Flat scissors , also called horizontal scissors , usually occur after a low speed overshoot in a horizontal direction . The defender reverses the turn , attempting to force the attacker to fly out in front and to spoil aim . The attacker then reverses , trying to remain behind the defender , and the two aircraft begin a weaving flight pattern . Rolling scissors . Rolling scissors , also called vertical scissors , tend to happen after a high speed overshoot from above . The defender reverses into a vertical climb and into a barrel roll over the top , forcing the attacker to attempt to follow . The advantage lies in the aircraft that can pull its nose through the top or bottom of the turn faster . In battles with aircraft that have a thrust - to - weight ratio of less than one the aircraft will quickly lose altitude , and crashing into the ground becomes a possibility . According to author Mike Spick , " Disengagement from a vertical rolling scissors is best made with a split - s and a lot of hope . " Guns defense . Guns defense maneuvering , or " guns - D " , is the last resort for a defender that fails to outmaneuver the attacker . Guns - D is a series of random changes in the defenders flightpath , intended to spoil the attacker ' s aim by presenting a constantly shifting target , and , hopefully , to maneuver out of the bullet stream ( hose ) . It consists of arbitrary speed changes , yaws , skids , slips , pitch - up s , and rolls , and is often referred to as " jinking . " Because the attacker must aim ahead of the opponent , the primary goal in guns - D is to disorient the attacker ' s aim by keeping the nose pointed in a different direction than the velocity vector ( the direction of travel ) , and is very effective at preventing the attacker from achieving a suitable guns solution . However , guns - D maneuvering still leaves the defender susceptible to stray bullets and " lucky shot " hits , and does little to improve the relative positional situation . Thus , it is only employed as a last - ditch defensive effort when nothing else works . High g barrel roll . A high g barrel roll is a last - ditch defensive maneuver , performed when the attacker has achieved a suitable guns solution , in order to cause an overshoot . The high g barrel roll is performed much more aggressively than a normal barrel roll . Range is critical to the success of the roll , and the defender will usually turn very hard , or employ other measures to draw the opponent very close before performing the roll . The roll is executed by applying hard back - stick pressure , creating the high g - forces , and adding hard rudder input to assist the ailerons in rolling the fighter . A high g barrel roll can be performed " over - the - top " , or it can be performed " underneath " , which is accomplished by rolling upside - down and beginning the maneuver from the inverted position . The high g barrel roll is an energy - depleting maneuver that rarely causes the attacker to fly out in front , but usually will result in a flightpath overshoot , a flat scissors , or , at the very least , will temporarily disrupt the attacker ' s aim . Defensive spiral . A defender that fails to outmaneuver the attacker can quickly become " out of airspeed and ideas " . The defensive spiral is a maneuver used by the defender when the kinetic energy becomes depleted and other last - ditch maneuvers can not successfully be implemented . The maneuver consists of dropping the nose low during the turn and going into a spiral dive , using gravity to supply the energy needed to continue evasive action . The defensive spiral becomes a rolling scissors performed straight down . The defender ' s goal is to stay out of phase with the attacker until the ground is dangerously close . The advantage usually goes to the aircraft that can decelerate quicker , and the defender will often cut the power and extend the speedbrakes in an effort to force an overshoot . If this attempt is unsuccessful , the defender will usually pull out of the dive at the last possible second , hoping to cause the attacker to crash into the ground .