FAAM CORE GPS-aided Inertial Navigation system, providing attitude, position and velocity data. 
This instrument is comprised of an Applanix POS AV 510 system, designed explicitly for the geo-referencing of airborne sensor data. As well as providing precise location data, GIN replaced the Honeywell H423 INU and the Navstar XR5 GPS in Autumn 2008, providing dynamics data essential to the operation of the Turbulence Probe and the subsequently derived wind data.

System Components

GIN consists of three main components:
  1. A 43dB L1/L2 antenna is installed on the spine of the aircraft - a position giving the best reception of standard Global Positioning Satellite (GPS) data
  2. A Litton LN200 Inertial Navigation Unit (INU) is rigidly mounted on the aft core console. This sub-system measures attitudes and accelerations in the x, y and z axes, aligned with those of the aircraft using experimentally-derived offsets which are implemented in real time by the POSAV system. These are in turn integrated to provide velocity information in the standard North, East, Down frame of reference.
  3. GPS and INU data are processed and combined by the POSAV Computer System (PCS), again in real time using Applanix's proprietary algorithm, and are output over the aircraft network for recording and display.


The following documents are only available to registered users:

The GIN installation is covered by the Core Consoles Technical Specification 

A report was produced at the end of the installation project to summarise the system and testing. On this basis the FAAM operations Committee recommended that the GIN should be operated as a Core instrument:
Basic Operation and Maintenance instructions are available, and form the basis for the standard operating procedures:
The GIN installation and operation Manual:
icon GIN Manual (4.39 MB) September 2006

POS AV 510



Although able to support a 200Hz data rate, GIN data are presently sampled at 50Hz and ingested at 32Hz in line with the data recording system regime. For all GIN parameters the stated measurement latency (manufacturer) is a maximum of 10ms. All GIN data are valid throughout the standard operating envelope of the aircraft (0-35kft, ±75°N). The parameters in table 1 are output as part of FAAM's standard submission and are additionally available in real time on every flight via the standard Data Recording System.

Table 1. GIN measured parameters and stated uncertainties


Uncertainty (1σ)

Pitch, Roll angles


Pitch/roll rates of change

0.0002 deg.s-1



Heading rate of change

0.0002 deg.s-1

Velocity (north, east, down)


Acceleration (x, y, z axis)

0.005 m.s-2

Longitude, Latitude


Altitude above WGS84 Ellipsoid


Drift Angle





Further Details

Contact Alan Woolley at FAAM