Precision-guided munitions (PGMs) that use a combination of GPS (Global Positioning System) and INS (Inertial Navigation System) to strike targets with high accuracy. These weapons are often conventional “dumb bombs” retrofitted with guidance kits (like JDAM), enabling all-weather, day/night precision without the need for continuous external guidance.
Key characteristics:
- GPS Guidance: Uses satellite signals to continuously update bomb position, correcting errors in flight.
- INS Guidance: An onboard inertial system (gyros and accelerometers) that tracks position even without GPS, though less precise.
- Accuracy: Typically achieves a Circular Error Probable (CEP) of 5–10 meters with GPS; ~30 meters or more if GPS is denied and only INS is used.
- Advantages: Independent of visual line-of-sight, unaffected by clouds, smoke, or darkness.
- Limitations: Fixed-coordinate weapons — cannot track moving targets unless upgraded with seekers (e.g., LJDAM). Vulnerable to GPS jamming or spoofing.
- Examples: JDAM family (GBU-31, GBU-32, GBU-38), SDB (Small Diameter Bomb).
Application in DCS World
- Modern DCS aircraft (F-16C, F/A-18C, A-10C) can employ GPS/INS-guided bombs, loading coordinates via targeting pods, markpoints, or JTAC grids. They offer simple yet powerful strike capability in poor weather or night operations.
- DCS does not simulate GPS jamming, degraded accuracy, or spoofing, so weapons are more reliable than in real-world contested environments. Moving-target capability (like LJDAM) is not fully modeled.
- Cadets should train in coordinate entry, markpoint generation, and multi-target JDAM programming, practicing both self-designation and JTAC-provided target coordinates to simulate real operational procedures.