Precision Approach Radar

AIM ¶ 4-5-4 — Precision Approach Radar

AIM 4-5-4: Precision Approach Radar (PAR) provides range, azimuth, and elevation guidance on final. Study guide for pilot written and checkride prep.

In Plain English

Precision Approach Radar (PAR) is a ground-based radar system designed primarily as a landing aid, not for sequencing or spacing traffic. Controllers can use PAR as the primary approach aid or to monitor other approaches (like ILS).

PAR provides three pieces of information about your aircraft on final:

Range (distance to touchdown)
Azimuth (left/right of centerline)
Elevation (above/below glidepath)

The system uses two antennas — one scanning vertically and one horizontally — to build this picture. Coverage is intentionally narrow because PAR only watches the final approach area:

Range: 10 miles
Azimuth: 20 degrees
Elevation: 7 degrees

The controller's scope is split into two halves: the upper half shows altitude and distance, and the lower half shows azimuth and distance. During a PAR approach, the controller issues continuous corrections ("on glidepath, on course") so the pilot can fly precise headings and descent rates without onboard approach guidance — useful when navaids are unavailable or as a backup. Note that PAR is informational guidance from ATC; it doesn't replace the pilot's responsibility to fly the aircraft.

AIM Source Text

FAA AIM ¶ 4-5-4

4-5-4. 4-5-4. Precision Approach Radar (PAR) PAR is designed for use as a landing aid rather than an aid for sequencing and spacing aircraft. PAR equipment may be used as a primary landing aid (See Chapter 5, Air Traffic Procedures, for additional information), or it may be used to monitor other types of approaches. It is designed to display range, azimuth, and elevation information. Two antennas are used in the PAR array, one scanning a vertical plane, and the other scanning horizontally. Since the range is limited to 10 miles, azimuth to 20 degrees, and elevation to 7 degrees, only the final approach area is covered. Each scope is divided into two parts. The upper half presents altitude and distance information, and the lower half presents azimuth and distance.

Oral Exam Questions a DPE Might Ask

Q1What is Precision Approach Radar (PAR) primarily used for?

Per AIM 4-5-4, PAR is designed as a landing aid rather than for sequencing and spacing aircraft. It can be used as a primary landing aid or to monitor other types of approaches.

Q2What information does PAR display, and what is its coverage area?

Per AIM 4-5-4, PAR displays range, azimuth, and elevation. Coverage is limited to 10 miles in range, 20 degrees in azimuth, and 7 degrees in elevation, covering only the final approach area.

Q3How is the PAR controller's scope organized?

Per AIM 4-5-4, each scope is divided into two parts: the upper half presents altitude and distance information, and the lower half presents azimuth and distance.

Related Paragraphs in AIM Chapter 4

¶ 4-5-1

Radar Capabilities and Limitations

¶ 4-5-10

ADS-R Rebroadcast

¶ 4-5-2

ATCRBS Secondary Surveillance Radar

¶ 4-5-3

Surveillance Radar

¶ 4-5-5

ASDE-X/ASSC Surface Surveillance

¶ 4-5-6