Military

FIGURE 1. SAME TARGET ATTACK. The fighter attacks from an IP "A" which is laterally separated from the artillery gun-target line and crosses the GTL at the target.

FIGURE 2: SEPARATE TARGET ATTACKS, CAS TARGET ALONG ARTY GTL. In this attack the fighter approaches from a lateral IP "A", crosses the GTL above the maximum ordinate + 1,000 feet, and exits to a different IP "T," again laterally separated from the GTL.

Altitude Separation Rules of Engagement Highlights

Common Definitions

The term "target area" refers to the artillery target grid with a 1,000-meter radius around it. When conducting a same target attack, you must consider the effect of the artillery fragmentation and the height of the trajectory within 1,000 meters of the target.

An "attack zone" is a cone or a fan that fighters ingress and/or egress within as they attack the target. The attack zone left and right limits are defined to the fighters as two magnetic attack headings which form a fan or cone with its apex at the artillery target.

"Ord 1" refers to the altitude of any given artillery trajectory at a point 1,000 meters short of the target, with a 1,000-foot buffer added to that altitude. Ord 1 is calculated to provide a safe altitude for CAS to cross an artillery target area while conducting a same target attack.

NOTE: The 3,000 feet AGL rule is designed to provide an absolute safe minimum attack altitude for aircraft. This is based on the appropriate 155-mm HE vertical fragmentation pattern with a buffer added. (The vertical fragmentation pattern accounts for NTC's average ground altitude which is 2,000 to 3,000 feet MSL).

DETERMINING "ORD 1"

Step 1: Draw a line from the firing unit to the suppression target. Determine the GTL range and the vertical interval (VI) between the firing unit and its target.

Step 2: Determine the charge to be used. Find the appropriate Tabular Firing Table (TFT) trajectory chart for the selected charge. Determine the trajectory arc that will achieve the target range and will also account for the vertical interval. If the target falls between two trajectory arcs, then select the higher arc.

Step 3: Determine the altitude of the selected trajectory arc at a point 1,000 meters short of the target along the GTL. Convert the trajectory altitude from meters to feet by multiplying the altitude by 3.3. Add 1,000 feet to the converted altitude, the sum of these two numbers is Ord 1. Use this Ord 1 altitude or 3,000 feet AGL, whichever is higher as the CAS Stay Above (SA) Altitude for a same-target attack.

Step 4: Express the SA Altitude in feet MSL to the fighters by adding the target altitude to ORD 1.

EXAMPLE PROBLEM:

NOTE: Use the trajectory chart from the 155-mm HE, TFT (on the next page), in conjunction with this sample problem.

Step 1. GT Range = 8,900 meters, Firing Battery will use Charge 5 WB (White Bag), and the vertical interval (VI) is + 300 meters. (Compare where this plots on the TFT Chart; Number 1 is marked on the example below.)

Step 2. In this example you determine that you must use the 600 mil arc. The 600 mil arc is selected because the + 300 meter VI at range 8,900 meters puts the target plot above the 500 mil arc. Now that you know which arc to use, determine the altitude of the trajectory at a point 1,000 meters short of the target, i.e., 7,900 meters. At this range, the altitude of the trajectory plots 1,200 meters. (For a visual representation, look at where the Number 2 plots on the example TFT Chart below.)

Step 3. Remember you must convert this altitude of 1,200 meters to feet Above Ground Level (AGL). You do this by multiplying 1,200 by 3.3 which equals 3,960 feet. Now add 1,000 feet and you have ORD 1, 4,960 feet AGL. Always round up to the nearest 100 feet for ease of expression to the fighters, in this case you would pass 5,000 feet AGL to the ALO.

Step 4. The ALO must determine the stay-above altitude for the fighters by adding the target altitude to the ORD 1 they receive from the FSO. In this example, assume the target altitude was 2,300 feet; the ALO adds the 5,000 feet (Ord 1) to his 2,300-feet target altitude and passes a stay-above altitude of 7,300 feet Mean Sea Level (MSL).

EXECUTING ALTITUDE SEPARATION MISSIONS

Suggested Duties and Responsibilities. The following tables provide the NTC-suggested responsibilities for executing altitude separation missions during same target and separate target attacks.

Notice that the FSO initiates the mission by a "SEAD" Call for Fire (CFF). The SEAD CFF is not doctrinal, but it is essential to execution. The CFF that initiates an altitude separation mission must be distinguishable to all members of the fire support system to prevent a misunderstanding by one or more agencies. While altitude deconfliction does provide protection from the Direct Support and/or Reinforcing battalion artillery fires, it does not protect fighters from other indirect fires, i.e., mortars or division artillery fires. Use a lateral separation method to deconflict all "outside" indirect fires from the simultaneous mission. Thus the SEAD CFF tells the DS FA battalion that it is safe for their fires to continue throughout the CAS attack, even though the Fire Support Officer (FSO) has put "ACA Blue" into effect.

The SEAD CFF can also serve to standardize coordination of the mission by a few simple commands; for example, consider using the terms "Continuous" or "Interrupted" as a method of control. Continuous could imply that the first artillery rounds will begin impacting one minute prior to the CAS TOT and continue for three minutes. Interrupted could mean fires impact 30 seconds prior to CAS TOT, resume one minute after the TOT and continue for three minutes. This terminology simplifies fires coordination and speeds up CFF transmissions.

Earlier in this chapter we mentioned the use of lateral and altitude separation techniques to safely execute close in air strikes. To ensure lateral separation, set up the ingress and egress control measures so that the fighters will only cross the GTL at the artillery target (same target attack). A rapid method to translate the appropriate attack headings to the fighters is to give them an "attack zone." Attack Zones are procedural control measures used by doctrine to safe aircraft approach angles during (ground) laser-designated target attacks. They are also used in the altitude separation TTP to identify a safe zone for aircraft to ingress and egress in relation to artillery gun target lines. (Refer to Joint Pub 3-09.3 for a summary of laser attack zones).

The NTC ROE requires aircraft to approach the GTL on an azimuth greater than 25 degrees offset. This 25-degree separation allows for the rapid deconfliction of multiple GTLs (remember firing batteries consist of six or more guns, spread out).

The benefits of attack zones are:

Attack zones should be as wide as possible without violating the 25-degree rule and/or jeopardize force safety. Assigning a single attack heading may be necessary for laser and night attacks to facilitate direct control, but it severely restricts aircraft flexibility and survivability.

SUMMARY

Although altitude separation is neither the silver bullet for simplifying CAS integration nor appropriate for all types of attacks, it is certainly a necessary airspace control measure to deconflict certain attacks. A unit with an established battle drill and thorough understanding of air operations will find that altitude separation can ease coordination for many attacks while achieving massing effects on the enemy.

Chapter 2: Defining the Army-Air Force 3-D Battlefield

Chapter 4: Close Air Support Planning