
CM170407AMA
SECTION 6 ENTERING AIR DATA TEST PARAMETERS
Air Data Parameters (Altitude, Airspeed, rates and AoA) can be commanded (entered) in
two ways:
1) by operating the MPS49 in the CONTROL mode. When the CONTROL mode is
active, the MPS49 starts to change the pressures as soon as a new air data value is
entered.
2) by operating the MPS49 in MEASURE mode. If it is desired that the MPS49 starts to
change pressures only after
all
the new air data parameters have been entered, it is
necessary to switch to MEASURE mode, then enter
all
the new target values and
then return to CONTROL mode by pressing the
CNTR
key. All the new commands
will then be activated together.
New target values can also be entered by using the triangle keys
▲
(to increase) or
▼
(to
decrease).
NOTE
If any value greater than the actual limits (the values programmed in the Limits
Screen) is selected, the value will be not accepted and instead the actual limit value
will automatically be entered. As an example, if an airspeed value of 999 knots is
entered while the limit value is set at 400 knots, then when the
ENTER
key is
pressed, the commanded value will become 400 knots.
6.1 ENTERING SPECIFIC COMMANDED VALUES
The MPS49 is operated by entering Commanded values for Altitude, Airspeed, Altitude
Rate, Airspeed Rate (or static pressure, dynamic pressure and corresponding rates) and
AoA from the Status Screen (FIG 5). To enter a Commanded value, the corresponding area
of the screen must be selected. The values can be selected by touching them, or with the
keyboard
and
keys.
The selected commanded values can be changed in two ways:
•
entering the new value using the numerical keypad, and pressing either
ENTER
or
the
or
keys when finished, to confirm the value. Press the
BACKSPACE
key
to delete the last digit. To cancel the editing, just delete all digits and confirm. While
the value is being edited, a cursor mark is shown. Once the value is confirmed, the
cursor mark disappears.
•
using the triangle keys
▲
and
▼
to increment or decrement the value. The value is
automatically confirmed.
The MPS49 will not accept values outside of the programmed limits (refer to SECTION 8).
6.2 MACH NUMBER AND AIRSPEED/QC LIMITS
The Mach number is calculated from the current altitude/Ps and airspeed/Qc values. The
MPS49 considers at any time both the airspeed and the Mach number limiting values, when
controlling altitude/airspeed or Ps/Qc.
•
If an
airspeed
command exceeds the
airspeed
limit, it is
rejected
.
•
If a
Mach
command exceeds the
airspeed or Mach
limits, it is
rejected
.
•
If an
airspeed
command exceeds the
Mach
limit only, it is
accepted
, but it will be
limited later.
When the
current
altitude and airspeed values result in a Mach number outside the limits,
the Mach number limit is enforced. The airspeed/Qc indication in the lower-right corner of
D.Marchiori Copyright
26