Page 2-6
GTX 327 Installation Manual
Revision K
190-00187-02
2.7
Cooling Air
The GTX 327 meets all applicable TSO requirements without forced air cooling. The application of
forced air cooling to the rear air nozzle of the GTX 327 is highly recommended to provide beneficial
cooling to the unit.
The GTX 327 was designed to handle a constant 450 PRF, with short periods of 1200 PRF. Rate limit is
set at 1200 PRF. A typical radar site would interrogate the transponder once every 5 to 10 seconds for
approximately 100 msec at a 400 PRF rate. In very high traffic areas with multiple ground stations and
TCAS traffic it is possible to have long term PRF rates above 450 PRF. The GTX 327 measures the unit
temperature and without forced-air cooling the reply rate will be reduced to protect the transmitter from
overheating.
2.8
GTX 327 Installation
2.8.1 Viewing Angle
Ensure that any mounting location will offer sufficient viewing angle. The display has been proven to
meet specifications when seen within the following envelope of viewing positions:
Direction
Pilot’s Viewing Angle
Left and Right
±45°
From Top
30°
From Bottom
10°