Indirect Fire Support and CAS

Purpose

When engaging fortified positions or coordinating with external fire support, clear procedures are necessary to prevent fratricide and ensure accurate effects on target. This article outlines how SPECTRE elements request and coordinate Indirect Fire Support (IDF) and Close Air Support (CAS) using a simplified 5-line call format.

⚠️ Note: This guide covers general procedures for coordinating indirect fire and air support. Specific procedures for artillery, fixed-wing CAS, rotary-wing CAS, and medevac coordination will be detailed in separate articles.

Definition

• IDF (Indirect Fire Support) refers to mortars, artillery, or other off-map indirect weapons.
• CAS (Close Air Support) refers to support from aircraft delivering munitions or performing strafing runs.

Both types of support are typically called in by a designated observer — often a JTAC or Section Leader — using closed-loop communication to minimize misfires and confusion.

Key Principles

• Fire missions must follow a clear, repeatable call format.
• Both caller and support asset must confirm each line.
• Never call for fire unless friendly positions are confirmed.
• Danger Close fire (within 200m) must be acknowledged and accepted by the observer.

Application

🔹 5-Line Fire Mission Format

1. Initiate Fire Mission
   "[Asset], this is [Callsign], fire mission, fire mission, over."

2. Friendly Location / Marking (Ommited for all IDF platforms) "Friendlies at grid [XXXXXX], marked by [Smoke / IR Strobe / Beacon], over."

   The reason for the omission is that it might be unnecessary for IDF platforms to have this information, as they may not be able to see the friendly positions. And could cause instances of friendly fire if grids get confused accidentally with target location.

3. Target Location
   "Target at grid [XXXXXX] / bearing and range / TRP, over."

4. Target Description (optional but helpful)
   "Enemy squad in tree line, marked by IR pointer, over."

Only useful for CAS, as IDF platforms will not be able to see the target.

5. Engagement Order
   "Fire for effect, [# rounds] [round type], pattern [e.g. west to east], danger close, over."

6. Acknowledgement by Fire Support Unit
   "Good copy, firing for effect, out."

7. BDA (Optional)
   After rounds impact, observer provides assessment: "Good effect on target, out."

All transmissions must be repeated back line-by-line by the support unit using closed-loop confirmation.

🔹 Roles and Chain of Command

• Fire missions should only be initiated by a JTAC, Platoon Leader, or Section Leader.
• Platoon Lead should be notified prior to calling CAS unless already delegated.
• JTACs or Section Leads are responsible for verifying:
  • Accurate grid or TRP
  • Friendly positions
  • Fire direction and safety distance

Common Mistakes

• ❌ Failing to confirm friendly positions before calling fire
• ❌ Omitting closed-loop confirmations
• ❌ Giving vague target descriptions or incorrect grid
• ❌ Calling Danger Close fire without accepting risk

Summary

Accurate and safe coordination of indirect fire and CAS is a force multiplier — but only when done correctly. The 5-line format keeps communications structured and predictable, ensuring support assets can respond confidently without endangering friendlies. Practice and brevity are key.

Specific platforms and protocols (artillery, fast air, rotary support, medevac) will be expanded in their own dedicated SOP entries.