K114 Issue No. 9
3 - 22 Operation
Airspeed Switch test
The following example shows how an airspeed switch an be functionally checked.
Note: For low airspeed switches (i.e. 130 knots) the Pt Only facility could be used.
Press LEAK MEASURE/CONTROL to enter control mode. Press SPEED/Qc.
If necessary, press RATE and enter a change of airspeed low enough to observe switch
operation.
Enter an Aim value below the operating limits of the switch (i.e., airspeed switch
operating at 130 knots ±2 knots set 127 knots).
Press ENTER and observe the airspeed changing.
Using the nudge facility, set to an appropriate step value, increase the Aim value.
Increase the Aim until the switch operates (contacts close) and record the value.
Change the Aim to above the airspeed operating range (i.e. 133 knots). Repeat the
steps, decreasing the Aim value until the airspeed switch operates (contacts open) and
record value.
This procedure can be repeated. If many operations of a switch are required use the
oscillating facility detailed in Full Set-up. The above method can be used for the other
parameters:
Examples:
Altitude switch - low altitude warning
- landing gear configuration warning
- height lock
Mach switch - Speed brake scheduling
- Mach cruise lock
To Next Page
Loading...
