Navigation Systems and Radar Services

Private Pilot ACS · Area VI · Task B · AIM, FAA-H-8083-25

Everything you need to know about Navigation Systems and Radar Services for your private pilot checkride. Aligned to FAA-S-ACS-6C Task VI-B, covering navigation systems and radar services.

VOR Navigation §

Frequency: 108.0–117.95 MHz. Always identify by Morse code before use. Radials extend FROM the station (named by magnetic bearing FROM the station).

CDI: Each dot = 2°. Full-scale deflection = 10°. TO flag = flying toward station. FROM flag = flying away. OFF/NAV flag = signal unreliable — do not use.

VOR check (IFR): Within 30 days. Methods: VOT (±4°), airborne checkpoint (±6°), ground checkpoint (±4°), dual VOR (±4° differential). Log date, place, bearing error, signature.
AIM 1-1-3; 14 CFR 91.171

GPS / RAIM / WAAS §

RAIM (Receiver Autonomous Integrity Monitoring): GPS receiver monitors its own signal integrity using redundant satellite geometry. Required for non-WAAS GPS IFR approaches — check RAIM before departure for planned arrival time.

WAAS (Wide Area Augmentation System): Ground-based corrections improve GPS accuracy to ≤3 meters. Provides its own integrity monitoring — no separate RAIM check needed. Required for LPV (Localizer Performance with Vertical guidance) approaches.

VFR GPS: No specific legal requirements but database must be current for IFR. Verify before any approach.
AIM 1-1-17; ACS PA.VI.B

VFR Flight Following §

How to request: After departure or en-route, call ATC and state: aircraft type, position, altitude, and destination. Request "VFR flight following."

ATC assigns a discrete transponder code, identifies you on radar, and provides:
• Traffic advisories (workload permitting)
• Weather deviation assistance
• Limited navigation assistance

Flight following does NOT transfer PIC responsibilities. Terrain clearance, airspace, collision avoidance, and fuel management remain the pilot's sole responsibility.
AIM 4-1-18

VOR Service Volumes §

T (Terminal): Up to 25 nm, up to 12,000 AGL.
L (Low altitude): Up to 40 nm, up to 18,000 AGL.
H (High altitude): 40–130 nm depending on altitude band.

Do not plan navigation using a VOR beyond its published service volume. Signals outside the SSV may be unreliable or interfere with other stations.
AIM 1-1-8