hose from the manifold assembly onto the
pressure port of the A/AS. After you remove the
static port filter, screw the altitude hose from the
manifold assembly into the static port of the
A/AS. Then connect the pitot pressure hose of
the test set to the airspeed port of the manifold
assembly. Set the pressure temperature test set
controls to the positions listed in table 6-1.
WARNING
The TTU-205-C/E test set must be
properly grounded to prevent injury to
personnel.
2. Connect the test set electrical plug to a
115-volt ac, 400 Hz, single-phase power source.
Set the test set power switch to ON. When the
pressure stabilizes, the static pressure ready light
and the pitot pressure ready light will illuminate.
Rotate the static pressure vent and pitot pressure
vent controls full clockwise. Position the airspeed
knots control to 500. Vary the airspeed trim
control as necessary to obtain 500 on the airspeed
knots indicator. It will take a few minutes for the
airspeed knots indication to increase to 500.
3. Position the airspeed leak test switch to
ON. Allow the pitot pressure to stabilize. At this
point, you should ensure that the pitot pressure
light goes out and that the leak rate is not more
than 15 knots in 5 minutes. Position the airspeed
leak test switch to OFF. The pitot pressure light
should illuminate and the airspeed knots should
return to 500. Position the airspeed knots
control to 280. Vary the airspeed trim control to
obtain 280 on the airspeed knots indicator.
WARNING
To prevent injury, make sure personnel
are clear of the A/AS plunger during
actuation.
4. Attach a 0- to 150-pound spring scale to
the arming key. Apply a straight pull on the scale
and remove the sensor arming key. The arming
key should release between 6 to 16 pounds of force
and the sensor plunger should remain extended.
5. Extend the plunger with the pull tool and
reinstall the arming key. Position the airspeed
knots control to 250 and vary the airspeed trim
control to obtain 250 on the airspeed knots
indicator. Remove the A/AS arming key and
observe the A/AS plunger retract. Again, use the
pull tool to extend the plunger and reinstall the
arming key.
6. Position the airspeed knots control to 50.
After the airspeed knots indication decreases to
the set value, position the test set power switch
to OFF. Rotate the static pressure vent and pitot
pressure vent controls full counterclockwise.
Disconnect the test set pitot hose from the
manifold and test set. Remove the pitot hose
assembly from the airspeed port of the manifold
and connect it to the altitude port of the manifold
assembly. Plug the airspeed port of the manifold.
7. Rotate the static pressure vent and pitot
pressure vent controls full clockwise. Position the
Table 6-1.—TTU-205-C/E Tester Control Settings
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