Leak Checks; Typical Aircraft Instrument Performance Checks - GE ADTS552F User Manual

E B A T O ADTS542F
XAMPLE ASIC IRCRAFT EST PERATION USING THE
Consult the ADTS limits values for the three predefined tables, HELICOPTER, FIXED WING and
MAX AERO in the SETTINGS menu (see section Settings). If a suitable protective limits match
cannot be found in one of the three predefined tables then choose CREATE NEW LIMITS and edit
your own custom limits table name and preferred values from the offered starting values. This
protected operation will require use of the Supervisor PIN code. Any attempt to enter limit values
greater than the ADTS pneumatic control maximums will create a warning to the user requesting
a lower value. Before attempting to create a new custom named limit, first check that there are
no more than 4 existing user named tables. A maximum of 5 only are allowed, but old unused
tables can be deleted as required.

Leak Checks

Since the leak status of the aircraft is initially likely to be unknown, it is recommended to perform
a preliminary assessment at low altitude and airspeed stimulus so as to minimise risk to the
aircraft instruments, should a high rate leak be present.
It is strongly recommended to enable the ADTS "AUTO LEAK RECOVERY" function. This will auto-
matically attempt to regain control of the aircraft pressures if the measured rates of change
(leak rate) exceed 3000 feet/min or 600 knots/min.
If no specific leak check procedure is described in the AMM, first select safe rates of parameter
change for the Ps and Pt channels according to aircraft type. It is suggested to start with simul-
taneous aims of 2000 feet and 200 knots, following the procedure described for the standard
equipment serviceability test described in section Standard serviceability test.
Correct any leak issues found with the hose connections or aircraft systems before proceeding
with further testing. The leak status of the ADTS alone may be verified using the procedures in
section ADTS leak check.

Typical Aircraft Instrument Performance Checks

The required aircraft specific procedures will be detailed in the AMM but the following generic
test is provided purely as an example of how the ADTS facilities might be best utilised.
The ADTS produces controlled altitudes based on the standard sea level pressure (zero feet refer-
ence) that is defined in the ICAO international standard atmosphere model. In order to correctly
check the aircraft instruments for accuracy against the ADTS, it is vital that the altimeter
baroscale datum adjustment is set to the same 1013.25 mbar (29.92 inHg).
Systematically enter the required aims for the Ps and Pt channel from each row of the test table
below. Aims may be entered either in aeronautical units or absolute/differential pressure units
according to the requirements of the AMM. For each of the six test row conditions, allow the ADTS
K0553 Revision D 84 [EN] English