ACM Flight School





Welcome to ACM (Air Combat Maneuvering) Flight School.

Air Combat Maneuvers

The Jane's manual for Air Combat Maneuvers states:

"In the world of combat, getting into position for a good shot is often called 'achieving a firing solution.'  It can happen in half a second, or it may take several minutes.  The manner in which you attain this position differs from conflict to conflict, so it's imperative that you develop a good reserve of combat maneuvers."

The following sections examine various air-to-air maneuvers and describes how to use them to your advantage during combat.

The Barrel Roll

  • Offensively, use the barrel roll if you're overtaking an enemy too quickly.
  • Defensively, use the barrel roll to force your attacker to overshoot and pass you.
  • Initiate a barrel roll by rolling slightly and applying pitch.  Keep the nose pitched to spiral around the axis of your flight path
The Barrel derives its name from the flight path the aircraft performs, circumscribing the shape of a barrel as the aircraft rolls round a central axis.  It is an energy management maneuver possessing both offensive and defensive potential.

Offensive Barrel Rolls

If you find yourself traveling too fast, you may both overshoot your foe and fly directly into his gun envelope.  This happens because your closure rate is too high, and you overtake your target.  The barrel roll provides an effective solution by wasting speed.

If you can't bleed enough speed with a barrel roll, pull back harder on the stick and execute a roll opposite the direction of your current turn.  The increase in pitch reduces airspeed, and the roll out turns you away from the target and keeps you from overshooting.  As you complete the roll,  you'll be back on your original course, but at a slower airspeed.

Defensive Barrel Rolls

Defensively, the barrel roll can be used to force a quickly approaching attacker to overshoot.  It can also maintain enough angle-off-tail to put you out of his lethal cone of fire.  Defensive barrel rolls must be carefully timed, however.  Initiate the roll too soon, and the bandit will follow you through it.  Start too late, and the bandit will have several shot opportunities before you begin the turn.  Perfect timing requires that you both surprise the enemy and deny him sufficient reaction time.


The Spiral Dive

  • Use a spiral dive as a last resort, and only if your aircraft has the superior turn radius.
  • Fall into a steep dive, then make a hard G-turn.  Throttle back midway through the turn and invert.  Pull the nose up hard to maneuver onto the enemy's tail.
If you use every maneuver imaginable and still can't shake an opponent despite a better turn radius, try a spiral dive.  You carry out this maneuver by leading your opponent into a steep dive as soon as he moves to one side of your tail and falls into an overshoot position.  He won't have a direct line of fire at you at that instant, but you can't dive for long without him re-achieving a firing solution.

End the dive quickly by taking advantage of your aircraft's superior turn radius and pulling hard pitch (but not so hard that you sacrifice maneuverability).  As you come out of the turn, reduce throttle, invert with a 180º roll, and pull up sharply again.  Your attacker probably won't notice that you've slowed down and will be forced in front of you.


The High-Speed Yo-Yo

  • Use the high-speed yo-yo to reduce AoT and bring a target into your firing cone.
  • Perform by relaxing a turn, then pulling up into a sharp climb.  Invert, then apply pitch to slide back down onto the enemy's tail at a smaller AoT.


  • The high-speed yo-yo is a basic component of offensive air combat and reduces AoT at the cost of increasing the distance between you and your target.  The yo-yo begins during a turning fight when you have assumed an aggressive position behind the bandit, but are stuck in lag pursuit and unable to bring your nose to bear.  In this case, you can use gravity to your advantage.

    Roll out slightly when your enemy initiates a break turn (maintaining lag pursuit), then pull the nose up.  At the apex of the climb, invert and roll back down onto your target's six o'clock position.  You'll be further away from him, but in a better firing position.

    Don't make the yo-yo too extreme.  Once you commit to a large one, you'll be unable to respond to any sudden changes the bandit may make.  Patiently work small yo-yos by bringing up the nose just above the horizon and chipping away at your AoT problem.  This will move you into the target's cone of vulnerability without pulling high G-loads.


    The Rollaway


    A variation of the high-speed yo-yo, the rollaway involves rolling away from the target's turn as you invert.  By diving and reversing direction with a 180º turn, you can drop in behind the defender's tail as he ends his break turn.  The principals of this maneuver are otherwise the same as the high-speed yo-yo.


    The Low-Speed Yo-Yo

    • Use the low-speed yo-yo when you have a good firing angle but need to bring the target in range.
    • This maneuver decreases range at the cost of increasing AoT.
    • Execute by diving inside a target's turn and gaining airspeed.  Then, pitch up and slide onto his tail once more.
    • The low yo-yo is the logical opposite of the high yo-yo, and achieves the exact opposite effect.  While the purpose of the high yo-yo is to decrease AoT (at the cost of increasing range), the low yo-yo is intended to to decrease range (at the cost of increasing AoT).

      Use the low-speed yo-yo when you have a good shot opportunity, but you're still outside your weapon's maximum range.  This often occurs in chases where the bandit has superior speed and is trying to run home in level flight.  You're chasing him, but he remains just outside your weapon's effective envelope.

      To get closer to your target, lower your nose below the horizon and dive.  This increases speed, but almost always forces you into lag pursuit and increases AoT.  A low yo-yo, therefore, almost always requires an immediate high yo-yo to correct the angle problem generated by the increase of speed.

      Be careful not to dive too steeply during this maneuver - you may be unable to bring your nose to bear on the target if it ends up too far above you.


      The Immelman

      • Use this maneuver to increase altitude and reverse direction.
      The Immelman is neither an offensive nor defensive procedure.  Instead, it is a high-thrust maneuver that changes your bearing and increases your altitude.  By pitching the nose up and climbing, you can execute one-half of a loop.  To terminate this maneuver, invert and execute a roll. (The amount of roll applied determines your new direction of flight, as indicated in the diagram.) This leaves you flying in a different direction, but at a higher altitude.  Once your wings are level, perform a half-roll again to reassume a vertical position.

      The Immelman is more useful for aircraft that have low-thrust capabilities.  Modern high-thrust aircraft can broaden this maneuver by making a vertical climb, then using an aileron roll to complete the half loop.
       


      The Split-S

      • Use the Split-S to increase airspeed or bleed off altitude.
      A Split-S maneuver is a diving half-loop that is useful when you want to disengage a threat.  It is a high altitude maneuver that requires a lot of vertical airspace, so make sure you're at least several thousand feet above the ground beforehand.

      During a turn, invert by rolling, then immediately pull back on the stick to go into a dive.  Your aircraft will rapidly accelerate and gain airspeed.  Pull back on the stick until the aircraft levels out, then ease into level flight.  You'll be uninverted, and you'll have a higher airspeed and lower altitude.

      The split-S has the advantage of providing a quick burst of speed.  Additionally, rolling while inverted adds the aircraft's lift vector to gravity, thus increasing the force of acceleration and adding speed.  On the down side, however, the increased speed increases the vertical turning radius, thus making it hard to pull the nose up into level flight.  Starting a split-S from low altitude, or maintaining too much speed during the dive, can prevent the aircraft from pulling out of the dive.

      The split-S makes a great escape maneuver in a guns-only environment because the rapid speed gain moves you out of gun range.  It's usually ineffective against missiles, since they have significantly longer ranges.