TB 9-4920-457-35
a. Performance Check
(1) Connect pneumatic pressure standard 0-120 InH20 inlet port to TI PRESS
PORT, using hose supplied with TI.
(2) On pneumatic pressure standard, connect BNC cable from 0-120 InH20 signal
output connector to EXT INPUT connector.
(3) Position controls on pneumatic pressure standard as listed in (a) through (e)
below:
(a) UNITS DISPLAYED switch to AIRSPEED.
(b) SOURCE pushbutton to EXT.
(c) RANGE pushbutton to 0-20.
(d) SENSITIVITY pushbutton to HIGH.
(e) Press RESET pushbutton.
(4) Open TI VACUUM VENT valve and close all other valves fully.
indication listed in table 6 (low range) or table 7 (high range). Pneumatic pressure
standard will indicate within the limits specified. Record TI error for each indication.
(6) If all indications are within tolerance, annotate correction chart and place in
holder on TI faceplate. The correction chart will show standard indications when TI
indicates nominal values.
b. Adjustments. No further adjustments can be made.
Table 6. Airspeed Indicator Check (Low Range)
Pneumatic pressure standard indications
Test instrument
(knots)l
airspeed indications
(knots)
Min
Max
20
17.5
(15)
22.5
(25)
30
27.5
(25)
32.5
(35)
40
38
(36.5)
42
(43.5)
50
48
(47)
52
(53)
60
58
(57)
62
(63)
70
68
(67)
72
(73)
80
78
(77)
82
(83)