Garmin AOA System, Owner'S Manual

190-01773-00 Rev. A

AOA System Owner’s Manual

1

   AOA System

OVERVIEW

The Garmin AOA (Angle of Attack) System is designed to improve the pilot’s 

awareness of the approximate available remaining lift of the aircraft’s wings.  The 
system calculates the approximate AOA (acute angle between the wing chord line and 
the relative wind) using pitot, AOA, and static air pressure inputs.  

When correctly calibrated, the system provides a visual approach AOA reference, 

as well as increasing caution and warning annunciations as the AOA approaches the 
wing’s maximum coefficient of lift (CLmax).

SYSTEM DESCRIPTION

The Garmin AOA System is comprised of three components; the GI 260 Indicator, 

the GAP 26 Probe, and the GSU 25 Air Data Computer.  The GAP 26 sends pitot and 
AOA air pressure to the GSU 25.  The GSU 25 measures the air pressure inputs from 
the probe and from an independent static source.  The GSU 25 then calculates the AOA 
information and sends it to the GI 260.  The GI 260 displays the AOA information to 
the pilot via ten color-coded LED annunciators.  When calibrated correctly (refer to 
the AOA System Installation Manual for calibration instructions), the system indicates 
AOA during critical phases of flight.  The system also provides awareness of AOA 
trends toward the target AOA for an approach, as well as visual alerting of critical 
AOA.  When connected to an audio panel or compatible audio system, the GI 260 
issues aural alerts of increasing frequency when the system approaches the critical 
angle of attack.

GI 260

AOA Indicator

Pneumatic

RS-232

GSU 25

Air Data Sensor Unit

GAP 26

Air Data Probe

AOA

Pressure

Pitot

Pressure

Static

Pressure

AOA

AOA System