smallest possible usable reflector targets. PAR alignment photographs shall be
used to assist the controller in ascertaining reflector location.
2. Controllers must then locate the:
a. Touchdown Reflector on the elevation scan
b. Touchdown and Centerline Reflectors on the azimuth scan. (In the absence
of a Centerline Reflector, the controller must locate the two Bracketing
Reflectors on the azimuth scan.)
NOTE
The controller should locate the End-of-Runway Reflector, if
installed at the station; however, this reflector is not used to
verify PAR alignment. The End-of-Runway Reflector is
used only to identify the runway threshold crossing point.
Most air stations PAR runways have a Centerline Reflector
and an End-of-Runway Reflector. When overrun arresting
gear is installed, End-of-Runway Bracketing Reflectors are
normally used to preclude conflict between an overrun
arrestment and the Centerline Reflector. If terrain and/or
airport configuration circumstances near the End-of-
Runway preclude the installation of an End-of-Runway
Reflector or Bracketing Reflectors adjacent to the End-of-
Runway, then the PAR alignment photographs should
identify appropriate RADAR return in the photographs to
assist the controller in making the most accurate ―over
landing threshold‖ advisory.
3. Controllers should turn OFF the cursor and range marks by adjusting the
CURSOR INTENSITY and RANGE MARK controls on the Indicator Processor-
Power Supply Front Panel Controls (beneath the controller s shelf/writing
surface).
4. Controllers should perform the following to check RADAR antenna alignment
accuracy. This check is similar to verifying that a permanent echo is at the
correct bearing on a surveillance RADAR system. This test verifies accuracy of
the RADAR and shall be accomplished on each PAR indicator.
a. Using the ANGLE VOLTAGE TD-OPERATE-6 NMI Switch on the Indicator
Power Supply Front Panel Controls (beneath the controller s shelf/writing
surface), select the TD (up) position. The controller should observe a sweep
trace on both azimuth and elevation displays.
b. Using the ANGLE VOLTAGE TD-OPERATE-6 NMI Switch, select the
OPERATE (center) position. The controller should observe and verify that the
sweep trace, left on the screen, bisects the touchdown reflector on both the
azimuth and elevation displays. Toggling the ANGLE VOLTAGE TD-
OPERATE-6 NMI switch from TD to OPERATE several times may be
necessary.
5-35
