Military

ACTIVE AIR DEFENSE

5-1. Fighting back is active air defense, but it is not undertaken as a one-on-one activity, that is, one soldier acting independently against one air threat. Rather, it is a coordinated group response either undertaken spontaneously or under command using prescribed engagement techniques. If a unit cannot coordinate its fire, it will be ineffective and waste ammunition.

ENEMY AIR THREAT

5-2. When passive air defense measures fail and enemy air threats are within range of organic weapons, units can conduct active air defense by shooting back. All Army units can engage enemy air threats to--

• Destroy the threat.
• Force the threat away from friendly positions.
• Force the threat to fly higher, so that friendly aerial platforms or ADA can destroy them.
• Spoil the hostile pilots' aim as they engage friendly forces.

RIGHT OF SELF-DEFENSE

SMALL ARMS FIRE AGAINST AERIAL PLATFORMS

SMALL ARMS USED FOR AIR DEFENSE

5-5. Small arms used in air defense incorporate the use of volume fire and proper aiming points according to the target. If your soldiers are trained to apply an appropriate sequence of engagement techniques for aircraft based on the rules for selecting an aiming point, the response will be automatic upon command. You will have effective air defense using the small arms available to your unit.

VOLUME FIRE

5-6. To engage aerial platforms effectively, you must follow some basic rules. The first rule to follow is to use a technique known as volume fire (Figure 5-1). The key to success in engaging enemy air is to put out a high volume of fire. The more bullets a unit can put in the sky, the greater the chance the enemy will fly into them. Even if these fires do not hit the enemy, throwing up a wall of lead in the sky can intimidate enemy pilots, ultimately breaking off their attack or distracting them from taking proper aim. One of the most important points about volume fire is that once the lead distance is estimated, you must aim at the estimated aiming point and fire at that single point until the aircraft has flown past that point. Maintain the aiming point, not the lead distance. Once you start firing, do not adjust your weapon.

ENGAGEMENT PRINCIPLES

5-7. The decision to fire is the unit commander's and is based on his judgment of the situation. The techniques for delivering fire are standard. Volume fire is the key to effective small arms fire against aerial threats. Every weapon (M16, M60, M249, and M2) must be used to engage the target with the goal of placing as many bullets as possible in the enemy's flight path. That does not mean that everyone fires in some random direction. Instead, each individual selects an aiming point in front of the target and fires at that point. This aiming point is determined using the football field technique.

Football Field Technique

5-8. The football field technique is a simple method of estimating lead distance. The theory is that most people have played or watched football and have a concept of how long a football field is. When told to lead the target by one football field, everyone aims at approximately the same point in space. One person's error in making the football field estimate will be offset by another person's error. The variation in aiming points will ensure that massed fire is delivered into a volume of space in front of the target rather than on a small point. Also, the differing perspectives from which the soldiers view the target will act to further distribute the fire over a volume of space. See Figures 5-2 and 5-3.

Aiming Points

FIRING POSITIONS FOR SMALL ARMS

5-10. Except for the prone position, the rifleman's basic firing positions stay the same (see Figure 5-4). Firing at aircraft when lying down means the individuals are lying on their backs (supine), aiming their rifles into the air. It will not take you long to learn to fire from some kind of cover and concealment, no matter how small. If you are in an individual fighting position (foxhole), stay there and return fire from the supported standing position. If you are not in an individual firing position, you should look for a tree, a large rock, or something to help support the weapon and provide protection. Use the following firing positions accordingly:

• You can use all the basic firing positions for air defense except the prone position. Instead, use the reverse position; lie on your back (supine) and point your weapon upward.
• Always take cover when available. If you are in an individual fighting position, stay there. Assume a supported standing position and return fire. A bipod on the M16 rifle assists you in firing your weapon more effectively at hostile aerial platforms.
• If cover and concealment are fairly good, use the high-kneeling position. If cover and concealment are less substantial, use the low-kneeling position.
• When using the M60 machine gun, the gunner will also fire from a protected position if possible. He needs to get the weapon up in the air. He can hold it up or use some support such as a tree limb. In an emergency, another soldier can act as a hasty firing support.

HELIBORNE INFANTRY AND PARATROOPERS

5-11. Infantry rappelling from a hovering helicopter should be engaged by first destroying the helicopter using volume fire. Airborne troops are more difficult to engage because of their rapid descent (approximately 10 feet per second). When engaging paratroopers, use machine guns by leading two body lengths below their feet. The Geneva Convention of 1949 and our rules of war prohibit engaging crewmen parachuting from disabled aircraft.

AIRCRAFT ENGAGEMENT TECHNIQUES FOR THE M2/M3 BRADLEY

5-12. The technique to obtain volume of fire is simple. All platoon vehicles engage with either the 25-mm gun or coaxial machine gun as designated by the platoon leader either by fire command or by TSOP. The TOW system should be used against helicopters only when necessary or as a last resort. Unit TSOPs should provide guidance for dismounted rifle fires in conjunction with supporting Bradley weapon systems in active air defense. All crews must be alerted to enemy air threat.

AERIAL ENGAGEMENT WEAPONS

5-13. Proper weapon and ammunition selection for the range and target is the key to success. Table 5-2 shows the weapons and the type of aerial targets that they can destroy.

FIXED-WING

HELICOPTER

SLOW   FAST

ARMORED UNARMORED

UAV

PARATROOPER

COAXIAL

YES

YES

NO

YES

YES

YES

HEI-T

YES

YES*

YES

YES

YES*

APDS-T

YES

YES*

YES

YES

YES*

APFSDS-T

YES

YES*

YES

YES

YES*

TOW

YES

NO

YES

YES

NO

*Secondary source if coaxial is not available or if out of coaxial range.

The 25-mm Gun

5-14. The 25-mm gun is effective against slow-moving FW aircraft, UAVs, and helicopters. When using the ADR sight, the gunner indexes 1,800 meters. The APDS-T, APFSDS-T, or HEI-T can be used against slow-moving, FW aircraft, UAVs, and helicopters. A continuous burst of 20 to 25 rounds (high rate), using TOT to adjust rounds on target, will sustain the volume of fire and kill the target. The APDS-T/APFSDS-T has a higher probability of hit than HEI-T; however, HEI-T has a higher probability of kill. At ranges beyond 1,200 meters, the APDS-T is more effective against helicopters. At ranges less than 1,200 meters, HEI-T is more effective against helicopters.

The Coaxial Machine Gun

5-15. The coaxial machine gun is used against FW aircraft, unarmored helicopters, UAVs, and airborne troops. It is ineffective against heavily armored helicopters. A continuous burst (50 to 100 rounds) at the aiming point is required, and TOT is used to bring rounds on target. The coaxial machine gun is effective out to 900 meters.

The TOW

5-16. The TOW weapon system should be used against stationary and slow-moving (up to 80 kilometers per hour) aerial targets beyond 1,700 meters. The Bradley must be stationary when engaging targets with the TOW. Before firing the TOW, the gunner must determine if there are any obstacles between the vehicle and the target that might interfere with the missile. If the target is moving, the gunner must determine if the target will be in sight long enough for the missile to reach it.

ENGAGEMENT TECHNIQUES

5-17. The crew's goal is to engage and destroy or suppress targets as fast as possible. (Refer to FM 23-1 for details.) Basic engagement procedures used for all engagements are--

1. The BC may be required to lay the gun for direction if the gunner's scan is away from the target. He will release control to the gunner (target hand-off) and issue the fire command.
2. Once the target is acquired, the gunner identifies and discriminates the target.
3. The BC then confirms the target and gives the Fire command.
4. The gunner completes his switch checks.

AIRCRAFT ENGAGEMENT TECHNIQUES FOR TANKS

5-18. Tank automatic weapons can be used effectively against UAVs, jets, and helicopters-- especially when several tanks are firing at the same time. The tank main gun can be used with good results against helicopters. It cannot be used effectively against jets because of the difficulty of tracking high-speed targets.

ENGAGING HELICOPTERS AND UAVS

5-19. Engage hostile targets immediately with the tank commander's automatic weapon (caliber .50 on most tanks) or with the loader's M240 machine gun on M1- series tanks. Firing quickly will--

• Alert other tanks that hostile targets are in the area.
• Destroy the target or spoil the pilot's aim.
• Give the tank commander time to engage the target with the main gun and coaxial, if desired.

Engaging with Tank Machine Guns

5-20. The tank commander's machine guns (or loader's machine gun on M1- series tanks) are useful weapons against unarmored threats. They can be fired quickly with volume fire. Before firing, ensure that the firing fan is clear of friendly units. Do not fire into them! Use the following guidelines:

• When the target is hovering or inbound, aim high with the machine gun and fire a continuous burst, adjusting onto target by observing the tracers. When firing against aerial targets with the M85 machine gun on M60- series tanks, use high rates of fire. Remember, at longer ranges tracers may appear to be striking the target when they are actually going under it.
• If the target is moving, track along its flight path using a lead of 50 meters-- half a football field. Fire a continuous burst, forcing the target to fly through the cone of fire.

Engaging Helicopters with the Tank Main Gun

5-21. The main gun should be used against armored threat helicopters. Speed is essential in engaging an attack helicopter. If an attack helicopter is hovering, it is probably preparing to fire a missile. Time is essential; fire any round that is preloaded. The M830A1 multipurpose antitank round is, by design, the most accurate round for engaging helicopters and should be the next round fired after any preloaded round. When engaging moving helicopters with an M1- series tank, smoothly track the target while aiming at the center of mass. Lase to the target, wait for the automatic lead to be induced (about 2 seconds), and fire. Be prepared to fire a second round using the same technique used for the first round.

ENGAGING FAST-MOVING AIRCRAFT

5-22. Because of the speed of jets, the best technique to use against them is to fire all tank automatic weapons in continuous bursts. If the jets are inbound, aim slightly above the nose or fuselage and fire. If the jet is crossing, use a lead of 200 meters (two football fields) and fire--letting the jet fly through the cone of fire from the machine guns. Do not try to track or traverse your fire with the jet--it flies too fast.

PRACTICE SEQUENCE OF ENGAGEMENT

5-23. A coordinated, high volume of fire will get results; precision is not important. Fire is delivered on command and not at the option of the individual soldier. The sequence of engagement might be as follows:

1. An aircraft commences an attack on your unit.
2. You or the air sentries spot the attacker. In either event, you are alerted to the attack and decide to engage the target.
3. You alert the unit. For example, "Air attack, inbound 5 o'clock, prepare to fire." (Table 2-1 in Chapter 2 of this FM lists the methods of giving alarms.)
4. Each member of the unit prepares his weapon to fire by placing the weapon in full automatic mode. He locates the target, finds his aim reference point as determined by the rules (Table 5-1), and waits for the command to fire.
5. The leaders estimate the right moment and give the command, "Fire."
6. Each individual fires at the aiming point until all ammunition is expended, or until ordered "Cease fire." Everyone immediately reloads and prepares to engage follow-on attackers.