TM 1-1520-240-MTF
4-32
NOTE
1. NO. 1 & NO. 2 ENGINE BEEP TRIM —
DECREASE for 8 seconds.
2. Note engine N1 readings.
3. Use the appropriate beep system (Normal or
Emergency on either engine) to indicate an
engine N1 less than the minimum specified for
the applicable ambient temperature as indicated
on figure 5-6 on the engine to be checked.
This procedure requires two-way communication
between the pilot and the mechanic. The pilot will
run the engine and note the N1 readings. The me-
chanic will notify the pilot when the bleed band
closes and adjust, if necessary.
NOTE
Bleed band must be open under this operating
condition.
CAUTION
Do not allow engine speed to go below mini-
mum N1 speed during this check.
4. Slowly increase appropriate beep trim while
maintaining rotor rpm within limits and determine
N1 when bleed band has just closed.
NOTE
Closure may be determined by inserting a 0.010
inch feeler gage under the bleed band.
5. The N1 at the bleed band closure point must be
within the limits specified on the chart on figure
5-6.
