C. Prepare to Test Weather Radar System
(1)
Place airplane such that it is pointed away from any large objects and toward an open area if the system tests requiring radiation from the antenna are to be performed. Observe the precautions in step (2) below. If the tests involving the display of radar video (echoes from terrain, rainfall, etc.) are to be performed, the airplane should be pointed so that the antenna sector scan includes hills or mountains preferably at various heights in the distance.
(2)
Place personnel warning lights around front of airplane in prominent areas to assure their visibility is optimum.
WARNING: DO NOT OPERATE WEATHER RADAR WHILE THE AIRPLANE IS BEING
_______ REFUELED OR DEFUELED AND DO NOT OPERATE IN ANY RADIATING MODE WHILE A FUELING OPERATION IS BEING CONDUCTED WITHIN 200 FEET OF THE ANTENNA OR AN EXPLOSION MAY OCCUR.
DO NOT ENTER AN AREA CLOSER THAN 10 FEET IN FRONT OF A SCANNING RADIATING ANTENNA AND 80 FEET IN FRONT OF A STATIONARY RADIATING ANTENNA TO PREVENT INJURY.
CAUTION: WHEN THE WEATHER RADAR IS OPERATED IN ANY MODE THAT
_______ RADIATES RF FROM THE ANTENNA, DIRECT THE NOSE OF THE AIRPLANE SO THE FORWARD 180-DEGREE SECTOR IS FREE OF LARGE METALLIC OBJECTS (HANGERS, TRUCKS, OTHER AIRPLANES, ETC.) FOR A DISTANCE OF 300 FEET AND TILT THE ANTENNA UPWARD 14 DEGREES OR DAMAGE TO RECEIVER MAY OCCUR.
EFFECTIVITY
AF 101-120, 123-156, 158,
159, 172-182, 185-199; SN 301-350; IB 405; GN ALL; CONFIG MD ALL; VM ALL 03 Page 507
Sep 25/94
34-43-00
(3) Place INS units 1 and 2 on tilt table and connect extension cables. INU's should face in same general direction as when installed in mounting rack in airplane.
NOTE: Provide conditioned air for the INU's (inertial navigation
____
units).
NOTE: If no pitch and roll stabilization accuracy tests of the
____ weather radar antenna are to be performed, the INU's need not be removed from their mounts or placed on the tilt table.
NOTE: If INS and navigation computer are programmed for the
____ interface gimbal slew test, this capability may be used (instead of tilt tables) for checking the pitch and roll stabilization accuracy tests of the weather radar antenna.
(4)
Provide electrical power. Refer to 24-22-00.
(5)
Prepare INS for operation and erect to at least coarse align mode. Refer to 34-41-00.
(6)
Close following circuit breakers on electronic circuit breaker
panel P7: WEA RAD (R/T-1) on 115 VAC essential radio bus WEA RAD (IND-1) on 115 VAC essential radio bus WEA RAD (R/T-2) on 115 VAC radio bus number 2 WEA RAD (IND-2) on 115 VAC radio bus number 2
D. Perform Weather Radar Operational Test (Ref par. 2)
E. Perform Pitch and Roll Stabilization Tests (using inputs from INS)
(1)
Make certain that all weather radar circuit breakers are open on circuit breaker panel P7 (see previous test), then open radome to gain access to antenna (Ref 34-43-03 for nose radome opening procedures). Swing radome fully open and latch in place.
(2)
At weather radar control panel, select STBY (standby) mode. If STAB (stabilization) on-off switch is provided on panel, set to STAB (or ON) position.
(3)
At R/T unit control panels, turn off transmitter in each R/T by placing XMTR switch to OFF (or press MOD OFF button).
(4)
At control panel, select NORM. Observe that antenna rotates in azimuth | 90 degrees about the zero degree (forward) position.
(5)
Place AZ (or SCAN DISABLE) switch on antenna to OFF, then carefully rotate antenna horizontally by hand to the zero azimuth (forward) position.
(6)
Place TILT control on control panel at 0-degree position and observe antenna is at 0 (| 1) degree position. Record reading of pitch indicator scale on antenna.
EFFECTIVITY
AF 101-120, 123-156, 158,
159, 172-182, 185-199; SN 301-350; IB 405; GN ALL; CONFIG MD ALL; VM ALL 01 Page 508
Sep 25/94
34-43-00
(7)
Rotate control panel TILT control and observe that antenna may be positioned from 14 degrees below recorded zero pitch position to 14 degrees above recorded zero position. Set TILT control at 0, |5, |10, and |14 degrees on control panel. Antenna position must correspond to the TILT control setting within | 2 degrees. Return TILT control to 0. position.
(8)
Set applicable INU tilt table for 20 degrees nose up and observe antenna points 20 | 2 degrees below the previously recorded zeroed position.
(9)
Set applicable INU tilt table for 20 degrees nose down and observe antenna points 20 | 2 degrees above the previously recorded zeroed position.
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本文链接地址：747飞机维护手册AMM CHAPTER 34 - NAVIGATION 第34章导航3(134)
