Chapter 6. REFERENCE AND SPECIFICATION
6.2 Main Pressure Display
6.2.1 F1 - F4
These function keys or soft-keys are used to select choices from menus. The menu choices may be
shown directly over the keys or displayed as a list. When a menu is displayed, press the appropriate
function key to select the required choice. CLEAR /QUIT can be used to leave a menu without
making a selection.
In aeronautical units (ft or m), this key selects an altitude display.
In pressure units (mbar, inHg etc.), this key selects a static pressure (Ps) display.
SETUP, [UNITS] can be used to change the units of display, if set-up mode is not switched
Before entering a new altitude or Ps aim, set the rate of change using the ROC/Ps RATE
In Control Mode (Aim display), enter a new altitude or Ps aim using the numeric keys. Use
LEAK MEASURE/CONTROL to exchange between control and measure mode.
In aeronautical units (kts, km/h), this key selects an airspeed (CAS or TAS) display. In
pressure units (mbar, inHg etc.), this key selects dynamic pressure and the display shows
The airspeed can be displayed and entered as either Calibrated Airspeed (CAS, Vc) or True
Airspeed (TAS, Vt).
Note: For testing purposes, Calibrated Airspeed equates to Indicated Airspeed
The Pt temperature value affects the calculation of TAS. The value of Pt temperature,
normally measured by the aircraft temperature sensor, can be changed by SETUP, SPEED/
Qc, [Pt TEMPERATURE] only in full set-up mode.
Use SETUP, SPEED/Qc, [CAS/TAS] to select CAS or TAS.
CAS/TAS can be changed in full set-up mode.
If the altitude aim is changed, after the entry of CAS, the Mach and TAS aim values change
while the CAS value remains unchanged*.
If the altitude aim is changed, after the entry of TAS or Mach, the CAS aim value changes
while the TAS and Mach values remain unchanged*.
If the Ps aim is changed, after the entry of Qc, then the Pt aim value changes while the Qc
If the Ps aim is changed, after the entry of Pt, then the Qc aim value changes while the Pt
* The display shows = symbol next to the parameter that remains unchanged.
10. SETUP, [UNITS] can be used to change the units of display, if set-up mode is not switched
11. Before entering a new CAS or Qc aim, the rate of change should be set using the RATE key.
72 | ADTS 405 Mk2 Instruction Manual-English
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