Radar Approaches
An approach where ATC, not your panel, provides course and altitude guidance. Two types: ASR (surveillance radar — non-precision, lateral guidance only) and PAR (precision approach radar — full lateral and vertical, accuracy comparable to ILS). Mostly available at military airports; some civil radar approaches exist. PAR allows no-gyro approaches for partial-panel scenarios.
ASR — Airport Surveillance Radar
- Type: Non-precision.
- Guidance: ATC provides lateral course guidance only (no glideslope) via radio. Higher minimums than precision approaches.
- Procedure: ATC calls descent to MDA, then issues missed approach at MAP unless visuals are acquired.
- Communication: ATC says things like "turn left heading 270, descend and maintain 2,400, two miles from runway." You comply and report visual contact.
- Use case: Backup approach when other approaches are unavailable, or when partial-panel makes self-flown approaches difficult.
PAR — Precision Approach Radar
- Type: Precision. Most precise radar approach.
- Guidance: ATC monitors and issues lateral and vertical guidance throughout. Comparable accuracy to ILS.
- Procedure: "Turning final, hold present heading. On glide path. On course, slightly left of course, correct slightly right. Approaching glide path, begin descent now. On glide path, on course."
- No-gyro approaches: When the AI or HI fails, you can request a no-gyro PAR. ATC tells you when to begin and end standard-rate turns ("turn right, stop turn"). You don't need a working heading indicator — ATC has the radar picture.
- Availability: Mostly military airports (Air Force, Navy, Coast Guard). Some civil airports retain PAR; many have decommissioned theirs.
When to request a radar approach
- Equipment failure — your VOR, ILS, or GPS receiver is failed or unreliable.
- Partial panel — AI or HI failed, no autopilot. PAR no-gyro is much easier to fly than self-flying a navaid approach in this configuration.
- Workload — IMC, single-pilot, busy radio environment. ATC vectoring is sometimes easier than self-navigating.
- Backup option — practical knowledge of radar approaches has saved pilots in real failures.
Radar approaches are not commonly used in modern operations because ILS and GPS approaches are widely available. But knowing they exist and how to fly them is worth the small amount of study time — they're a useful tool when the others aren't available.
Published minimums
Published minimums for PAR, ASR, and circling approaches are in the Terminal Procedures Publications (TPPs), not on individual approach plates the same way ILS and VOR are. Check the TPP for the destination airport before requesting.
Helicopter visibility reduction (AIM 10-1-2) applies to ASR approaches. PAR minimums are typically equivalent to ILS minimums.