(5)
Excessive deviation below the glide slope.

 B. The GPWS consists of a ground proximity warning computer, a warning XA light labeled GPWS, a test switch, a glide slope advisory light XA labeled BELOW G/S, and an inhibit switch labeled PUSH TO INHIBIT,
 a monitor light labeled GPWS INOP. In addition, the warning is audible through the pilots' interphone speakers.
 C.  On SN 351, ground proximity warning system provisions provided, with the GROUND PROXIMITY TEST switch, BELOW G/S light and GPWS light labelled INOP.
 D.  Primary power for the system is 115 volts ac supplied from the essential flight instrument bus in panel P7 through a circuit breaker labeled GROUND PROX WARN CMPTR.
 E.  The CADC also supplies 26 volts ac as a reference voltage for the altitude rate circuits.
 2.  Computer
________
 XA A.  On LH ALL, the ground proximity warning computer (GPWC) is rack-mounted on shelf No. 1 and electronic equipment rack E2, the GPWC consists of a logic and power supply module, a comparator and closure warning module and audio modules. A power transformer and an interference capacitor are also mounted in the rear of the chassis above the electrical connector. In addition, a test switch and fault lamps are installed on the front
 XA  panel. (Sundstrand Computer P/N 965-0376-088)
 XA B.  On AT ALL, the ground proximity warning computer (GPWC) is rack-mounted on shelf No. 1 and electronic equipment rack E2, the GPWC consists of a logic and power supply module, a comparator and closure warning module and audio modules. A power transformer and an interference capacitor are also mounted in the rear of the chassis above the electrical connector. In addition, a test switch, mode annunciators, reset switch and fault lamps are installed on the front panel.
 XA  AF ALL EXCEPT 157, 161, SUNDSTRAND COMPUTER P/N 965-0376-070; AF 157, 161, SUNDSTRAND COMPUTER P/N 965-0376-088.
 EFFECTIVITY

 AF ALL;LH ALL;SN ALL;  CONFIG 1 AT ALL;GN ALL;MD ALL;  ATG Page 1 VM ALL  Sep 25/94

34-46-00
.................................................................................XA

PILOT'S LIGHTSHIELD
FLIGHT ENGINEER'S SEE A
INSTRUMENT PANEL SEE C
2
CENTER INSTRUMENT PANEL
CENTER SEEC 1
INSTRUMENT PANEL
SEE B
GROUND PROXIMITY WARNING COMPUTER E-2 RACK SHELF NO. 1
PUSH BELOW GPWSTO G/SINHIBIT
A
1  AF ALL 
VM ALL MD ALL AT ALL GN ALL  TEST PROXIMITY GROUND  INOP GPWS 
2  LH ALL, SN ALL (AEB AF 34-364)  B  C 

Ground Proximity Warning System Component Location
Figure 1

EFFECTIVITY

AF ALL; LH ALL; SN ALL; CONFIG 1AT ALL; GN ALL; MD ALL;799 Page 2 VM ALL; Apr 25/85
34-46-00
 C.  On AF ALL; SN ALL; GN ALL; MD ALL; VM ALL, the ground proximity warning computer (GPWC) is rack-mounted on shelf No. 1 of electronic equipment rack E2. The GPWC consists of a wired chassis, power supply module, central processor unit (CPU) card, and an input-output card. The front panel contains a convection type heat sink serving the power supply module, 6 LED indicators, and a test pushbutton. The rear panel contains 2 installation connectors and an
 XA  ATE connector to be used during bench maintenance. (TRT Computer)
 3.  Warning Indicator Light (Fig. 1)
_______________________
 A.  A rectangular shaped red warning light is installed on the pilot's lightshield. The light has a light-test feature which is controlled by the master dim and test switch. Access to the bulbs and a fuse within the light assembly is provided by removing the lens cover. The warning light is labeled GPWS.
 B.  The light comes on to provide a visual indication that the GPWC has
 generated a warning of an unsafe flight path. XA 4. ______________SN ALL (AEB AF 34-394)
Advisory Light (Glide Slope) ALL aircraft except:
A.  A rectangular shaped amber advisory light labeled BELOW G/S is installed on the pilots' lightshield. Access to the bulbs and a fuse within the light assembly is provided by removing the lens cover.
 B.  The light comes on to provide a visual indication that the airplane is below the glide slope beam when an ILS frequency is selected and the landing gears are down. The warning light has a steady illumination.
 5.  GPWS Test Switch
________________
 A.  The GPWS TEST switch is located on the center instrument panel. It
 provides a confidence check of the system either on ground or in flight. XA 6. __________________
G/S Inhibit Switch All aircraft except SN ALL (AEB AF 34-394)
 XA A.  The G/S inhibit switch is located on the pilot's lightshield. The switch will inhibit the glide slope warning and cancels the advisory light when pressed. The switch is labeled PUSH TO INHIBIT.
　
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