TB 9-4920-363-24
b. Adjustments. No adjustments can be made.
Pneumatic pressure standard indications
Test instrument indications
(fpm)
(fpm)
Min
Max
1000
800
1200
2000
1700
2300
3000
2700
3300
4000
3600
4400
45001
4050
4950
-500
-400
-600
-1000
-800
-1200
-2000
-1700
-2300
-3000
-2700
-3300
-4000
-3600
-4400
-4500
-4050
-4950
1Maintain
climb rate indication of 4500 fpm for 3 minutes, close both vacuum control valves (fully cw), set
power switch to OFF, and proceed to -500 fpm indication.
10. Airspeed Indicator
a. Performance Check
(1) Connect pneumatic pressure standard 5 psid inlet port to TI airspeed connector,
using TI hose assembly.
(2) Set pneumatic pressure standard to indicate airspeed in knots.
(3) Position TI controls as listed in (a) through (f) below:
(a) VACUUM selector valve to OFF.
(b) PRESSURE selector valve to AIRSPEED.
(c) AIRSPEED case leak control valve to OPEN.
(d) VACUUM INCREASE and DECREASE control valves to open position.
(e) PRESSURE INCREASE and DECREASE control valves to closed position.
(f) POWER switch to ON.
(4) Slowly adjust TI PRESSURE INCREASE and DECREASE control valves
until TI indicates 50 knots. Pneumatic pressure standard will indicate between 48 and
52 knots.
(5) Slowly adjust TI PRESSURE INCREASE and DECREASE control valves for
each TI indication as listed in table 5. Pneumatic pressure standard will indicate within
the limits specified.