Partial Panel & Radio Navigation
Private Pilot ACS · Area VIII · Task F · FAA-H-8083-15, FAA-H-8083-3
Everything you need to know about Partial Panel & Radio Navigation for your private pilot checkride. Aligned to FAA-S-ACS-6C Task VIII-F, covering partial panel & radio navigation.
Partial Panel Flying §
Vacuum failure takes the AI and HI offline. Suction gauge drops below green arc (4.5–5.4 in Hg). Cover or mark the failed instruments to prevent fixation on erroneous readings.
Remaining reliable instruments:
• Turn coordinator (electric gyro — survives vacuum failure) → bank control
• Magnetic compass → heading reference (with ANDS/OSUN corrections)
• Altimeter → altitude
• VSI → pitch trend
• ASI → pitch and energy
Reduce workload: fly straight and level. Communicate with ATC. Plan for lower complexity and consider declaring an emergency if in IMC.
Remaining reliable instruments:
• Turn coordinator (electric gyro — survives vacuum failure) → bank control
• Magnetic compass → heading reference (with ANDS/OSUN corrections)
• Altimeter → altitude
• VSI → pitch trend
• ASI → pitch and energy
Reduce workload: fly straight and level. Communicate with ATC. Plan for lower complexity and consider declaring an emergency if in IMC.
PHAK Ch.8; AFH Ch.7; ACS PA.VIII.F
Compass Turns (Partial Panel) §
Magnetic compass errors in turns (northern hemisphere):
OSUN — Overshoot North, Undershoot South:
• Turning TO a northerly heading: start rollout early — compass lags behind, appears to overshoot north.
• Turning TO a southerly heading: continue past the heading — compass leads, appears to undershoot south.
ANDS — Accelerate North, Decelerate South:
On easterly or westerly headings: acceleration causes apparent northerly turn, deceleration causes apparent southerly turn.
Lead/lag amount ≈ local latitude in degrees.
OSUN — Overshoot North, Undershoot South:
• Turning TO a northerly heading: start rollout early — compass lags behind, appears to overshoot north.
• Turning TO a southerly heading: continue past the heading — compass leads, appears to undershoot south.
ANDS — Accelerate North, Decelerate South:
On easterly or westerly headings: acceleration causes apparent northerly turn, deceleration causes apparent southerly turn.
Lead/lag amount ≈ local latitude in degrees.
PHAK Ch.8