TM55-2840-251-23
Section X ENGINE TESTING (Continued)
1-94
GROUND TEST OF ENGINE
INSTALLED IN AIRCRAFT
(Cont)
4.
Check No. 3 - Part Power
Trim. (Cont)
c.
Part Power Trim Check.
(1)
Engine is trimmed by adjusting gas
generator maximum speed stop to part power trim check
curve supplied by aircraft manufacturer. This curve allows
setting of maximum Ng at reduced power and at all off-
standard atmospheric conditions.
CAUTION
Observed gas generator speed should not
exceed 97.1% Ng (36400 rpm) during part
power trim check and subsequent gas
generator maximum speed adjustments.
Interturbine temperatures should not exceed
the value shown by maximum uptrim line on
aircraft manufacturer's part power trim check
curve.
(2)
To determine expected power output for
an engine under static conditions, proceed as follows:
(a)
Obtain ambient air temperature.
(b)
Obtain field barometric pressure
(not corrected to sea level).
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