Section 16 Gsu 25/25B (Ahrs/Air Data Sensor Unit) Installation; Equipment Description - Garmin G3X Installation Manual

16 GSU 25/25B (AHRS/AIR DATA SENSOR UNIT) INSTALLATION
NOTE
References to the GSU 25 throughout this manual apply equally to the GSU 25B except
where specifically noted.
The GSU 25 can be installed as part of the G3X system. This section contains general information as well
as installation information for the GSU 25. Use this section to mount the GSU 25 unit.

16.1 Equipment Description

NOTE
There is no TSO/ETSO applicable to the GSU 25.
The GSU 25 is intended for experimental aircraft and LSA (light sport aircraft) markets. The Garmin
GSU 25 Sensor Unit is not a TSO-certified product and has received no FAA approval or endorsement.
The GSU 25 is intended to be used as a part of the G3X system and it is not suitable for installation in type-
certificated aircraft.
The GSU 25 is an LRU that provides AHRS and Air Data information in a single mechanical package.
The GSU 25 interfaces to a remote mounted GMU 22 for heading information and also computes OAT and
TAS from inputs provided by the GTP 59. The GSU 25 does not provide engine/airframe interface, see
Section 9 for engine/airframe interface using the GEA 24. Up to three GSU 25 units may be installed to
provide redundancy and cross-checking of attitude, heading, and air data.
The GSU 25 provides the functions in Table 16-1.
Air Data
Pressure Altitude
Density Altitude
Vertical speed
Mach Number
Indicated Airspeed
True Airspeed
Angle of attack
Outside and total air
temperature (via GTP 59)
190-01115-01
Rev. AA
Table 16-1 GSU 25 Functions
Interfaces
CAN (1)
RS-232 (2 TX/2 RX)
OAT Probe (GTP 59)
Magnetometer (GMU 22)
(1 RS-232 TX/ 1 RS-485 RX)
G3X/G3X Touch Installation Manual - GSU 25/25B Installation
AHRS
Magnetic Heading (with input
from GMU 22)
Pitch Angle
Roll Angle
Linear Accelerations
Pitch, Roll, Yaw Rotation Rates
3 axis angular rates
3 axis accelerations
Page 16-1