(3)
The state change is sensed inside the PSEU as a logic one or zero in digital form. One can look for the same logic value of one or zero in the CMCS for use during system fault isolation or during system tests.
(4)
The sensors can simulate a state change with proximity switch sensor actuators or deactuators. When the actuators or deactuators come near to the sensor face they cause the sensors to change state.
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(5)
The Landing Gear Sensor produces a logic one state at the output of the proximity card for a target near condition. A near condition also produces a logic one or high bit state when you view sensor values through the CMCS.
(6)
The Landing Gear Door sensors produce the opposite logic result. The target near condition for all landing gear door produces a logic zero at the output of the proximity card. The target near condition also produces a zero or low bit state when viewed from the CMCS terminal.
C.
Nose Gear Sensors (Fig. 1)
(1)
The nose gear squat sensors are located on the forward side of the nose gear shock strut outer cylinder. The targets are attached to a bracket assembly on the bottom of the upper torsion link. The targets come near to the sensors when the nose gear is extended. These sensors supply a signal to the nose gear steering relays. The signals from the sensors are also used to determine PSEU BITE air mode or ground mode.
(2)
The nose gear up sensors tell when the nose gear is in the UP position. The sensors are in the pressure pan recess on the nose gear wheel well aft bulkhead. The retraction actuator trunnion crank is the target. When the nose gear is in the up and locked position, the sensors are near the targets.
(3)
The nose gear lock sensors tell that the nose gear is locked in one of the two positions, up or down. When the nose gear is in the up position, the drag strut assembly is horizontal. In the down position, the drag strut assembly is vertical. The sensors are on the upper drap strut and the targets are on the lock link assembly. Both positions allow the sensors near the targets.
D.
Body Gear Sensors (Fig. 2)
(1)
The body gear downlock sensors tell that the body gear is down and the jury strut assembly is in the locked position. The body gear downlock sensors are on the upper jury strut at the jury strut apex. The targets are on the lower jury strut.
(2)
The body gear uplock sensors tell that the body gear is up and the uplock mechanism is in the locked position. The uplock sensors are next to the uplock hook. The targets are in the uplock mechanism. The targets are near the sensors when the body gear is in the up and locked position.
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NOSE GEAR
LOCK SENSORS
SEE B
NOSE GEAR UP SENSORS AFT BULKHEAD
SEE A NOSE WHEEL WELL
NOSE GEAR
SQUAT SENSORS
SEE C
PRIMARY UP
SENSOR (S396)
ALTERNATE UP
SENSOR (S411)
FWD
PRIMARY LOCK UPPER DRAG
UPLOCK SENSORS
SENSOR (S397) STRUT
A
PRIMARY SQUAT SENSOR (S800, ON RIGHT SIDE OF MOUNTING BRACKET)
ALTERNATE LOCK SENSOR (S424)
ALTERNATE SQUAT SENSOR (S801, ON LEFT SIDE OF MOUNTING BRACKET)
NOSE GEAR LOCK SENSORS
FWD NOSE GEAR SQUAT SENSORS B
C
Nose Gear Sensors Figure 1
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