How Beyond-Visual-Range (BVR) Air-to-Air Missiles Lock their Targets Compared to Short-Range Missiles

The dogfight isn't the only game in town for air combat anymore. Modern aerial warfare extends far beyond the visual range, thanks to Beyond-Visual-Range Air-to-Air Missiles (BVR) and their shorter-range counterparts. But how exactly do these missiles lock onto their targets? Let's break down the steps involved for both BVR and Short-Range Missiles.

BVR AAMs (e.g., AIM-120 AMRAAM, R-77):

1. Target Detection and Tracking: The launching aircraft's radar system detects and tracks the target aircraft. This involves emitting radar waves and analyzing the reflected energy to determine the target's position, speed, and direction.

2. Lock-on and Data Sharing: The pilot locks onto the target with the radar, which continuously paints the target with radar energy. This lock provides the missile's guidance system with target information. Additionally, data like target location and predicted future position may be shared with the missile's onboard computer before launch.

3. Launch and Initial Guidance: The BVR AAM is launched. In the initial phase, the missile relies on data from the launching aircraft or an external source (like an Airborne Warning and Control System - AWACS) for guidance. This allows the launching aircraft to break radar lock and maneuver freely.

4. Active Seeker Activation: Once within a certain range (determined by the missile's seeker capabilities), the missile's active radar seeker turns on. This seeker emits its own radar waves and homes in on the reflected energy from the target, achieving autonomous guidance.

5. Terminal Homing and Engagement: The missile's seeker refines the target's position and adjusts its course for interception. The missile maneuvers based on the seeker data until it impacts the target.

Short-Range AAMs (e.g., AIM-9 Sidewinder, R-73):

1. Visual or Radar Acquisition: The pilot visually identifies the target or acquires it through the aircraft's radar. Short-range missiles often have simpler targeting systems compared to BVR missiles.

2. Lock-on and Launch:  The pilot locks onto the target using the aircraft's radar or an infrared seeker (heat-seeking) in the missile itself. The missile relies on this continuous lock for guidance.

3. Active Tracking and Engagement: The missile homes in on the target using the locked-on signal from the radar or the heat signature detected by the infrared seeker. The missile maneuvers aggressively to close the distance and engage the target in a dogfight scenario.

Key Differences:

• Lock-on Reliance: BVR AAMs can achieve launch and initial guidance without continuous lock from the launching aircraft. Short-range missiles require a lock throughout the flight for guidance.
• Seeker Technology: BVR AAMs use active radar seekers that become operational mid-flight. Short-range missiles can use radar or infrared seekers, both requiring continuous lock-on.
• Engagement Range: BVR AAMs are designed for long-range engagements beyond visual range. Short-range missiles are effective at much closer distances, often within visual range.

Overall, BVR AAMs offer greater launch flexibility and standoff capability, while short-range missiles prioritize agility and fast target acquisition for close-quarters combat.