Instruct: Given a question, retrieve passages that answer the question.
Query: What is the most basic fighter plane maneuver?
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.[38]
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:
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.[26][40]
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". The modern Immelmann differs from the original version, which is now called a stall turn or "Hammerhead turn". The Immelmann turn was an effective maneuver in the early part of the war but as aircraft technology advanced and fighter engines became 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.[2]
Basic fighter maneuvers (BFM) are actions that a fighter aircraft makes during air combat maneuvering, historically known as dogfighting. 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.
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.[40]
During the repeated brief passes it is occasionally possible to get off what is called a "snap shot" (A snap shot is an opportunistic shot of brief duration, brief because of the rapid change of the LOS (line-of-sight) to the target caused by the aircraft's maneuvering in different planes of motion. The preferable "tracking shot" opportunity lasts longer; as long as the attacker can maintain a constant LOS to the bandit, accomplished by maneuvering in the same plane of motion as the bandit. The process of getting into the same plane of motion as a bandit and setting up a tracking shot is called "getting into the saddle" or "saddling up".) at the opponent fighter, although due to the typically close range of the scissors, usually only guns may be used for this "snap shot". This process of 180 degree rolls and reversed turns can be repeated many times while each pilot seeks a positional advantage through energy management, and seeks to avoid a disadvantage.
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 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.[4]
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.[19]
Dissimilar air combat training (DACT) consists of 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, two against two, two against many, 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.
A sandwich maneuver begins with two defenders flying line-abreast (side by side at the same altitude), with typically about a mile of lateral separation. When an attacker maneuvers onto the tail of one aircraft, the defender will make a sharp turn away from the wingman. At the same time, the wingman turns in the same direction as the defender. When both fighters turn 90 degrees, they will come into single-file alignment with each other, "sandwiching" the attacker in the middle. Because the attacker is distracted chasing the defender, this allows the wingman to maneuver onto the attacker's tail for an easy shot.[13]
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.
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.[34]
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".
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.[24][40][44]
Basic fighter maneuvering theory recognizes two different types of scissors maneuvers; the flat scissors and the rolling scissors.
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.[25]
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.[13]
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.[45][46]
Basic fighter maneuvers consist of many varying 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 almost 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.[1]
Aerobatics consist of five basic maneuvers: Lines (both horizontal and vertical), loops, rolls, spins, and hammerheads. Most aerobatic figures are composites of these basic maneuvers with rolls superimposed. A loop is when the pilot pulls the plane up into the vertical, continues around until he is heading back in the same direction, like making a 360 degree turn, except it is in the vertical plane instead of the horizontal. The pilot will be inverted (upside down) at the top of the loop. A loop can also be performed by going inverted and making the same maneuver but diving towards the ground. It can be visualized as making a loop of ribbon, hence the name it is given (there is an animation depicting a loop on the bottom of this page). A roll is simply rotating the plane about its roll axis, using the ailerons. It can be done in increments of 360 degrees (i.e. four short 90 degree rolls will bring the aircraft back to its upright position). A spin is more complex, involving intentionally stalling a single wing, causing the plane to descend spiraling around its yaw axis in a corkscrew motion. A Hammerhead (also known as a stall turn) is performed by pulling the aircraft up until it's pointing straight up (much like the beginning of a loop), but he continues to fly straight up until his airspeed has dropped to a certain critical point. He then uses the rudder to rotate the aircraft around its yaw axis until it has turned 180deg and is pointing straight down, facing the direction he came from. The aircraft gains speed, and he continues back exactly the way he came. It is also known as a "tailslide", from the yawing turn, which is different from the typical method of turning an aircraft in the pitch axis.
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.[23]
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.[5] 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.'".[7]
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.
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.[35]