TM 55-1520-240-23-3
4-2.4
PERFORM POWER ASSURANCE CHECK
(Continued)
4-2.4
b.
Move the NO. 2 ENGINE CONDITION lever
to a position between FLT and GND until the
NO. 1 engine torque is stabilized between 60
and 70 percent. Stabilize for 15 seconds.
c.
Activate the DECU PAC switch to the NO.
1 engine position and release. Note the
last hexadecimal digit series displayed.
Determine the appropiate PACN adjustment
value from figure 1, current FAT. Combine the
PACN FAT adjustment value to the DECU
hexadecimal display. Record this value in
the PAC LOG.
d.
Move the NO. 2 ENGINE CONDITION lever
to FLT position.
e.
Repeat steps 2b thru 2d for the opposite
engine.
If the PAC value logged or the
adjusted PACN is BELOW the
established PAC trigger value during
the ground PAC, do not fly the aircraft.
If the PAC trigger value logged or
the adjusted PACN is BELOW the
established PAC trigger value during
the hover or flight PAC, abort the
mission and return the aircraft to the
maintenance facility. Troubleshoot the
engine indicating systems, inspect
engine for FOD, check PTIT thermal
couples, and check for cleanliness. If
needed, perform engine compressor
wash. If the engine shows no
signs of damage and the indicating
sytems are operating correctly,
complete a MCP or MPC PAT and
establish a new trigger value IAW TM
55-1520-240-MTF.
NOTE
The in-flight PAC should be performed
prior to or at the beginning of mission
execution.
NOTE
If the engine torque is between 60
and 70 percent when the aircraft is
established in flight at an airspeed
between 80 KIAS to 100 KIAS,
adjustment of the engine condition
levers are not required.
3.
In-Flight:
a.
Establish aircraft at 80 to 100 KIAS, PA - SL
to 14,000 FT and FAT of -40ºC to +54ºC.
b.
Move the NO. 2 ENGINE CONDITION lever
to a position between FLT flight and GND
ground until the NO. 1 engine torque is
stabilize for 15 seconds.
c.
Activate the DECU PAC switch to the NO.
1 engine position and release. Note the
last hexadecimal digit series displayed.
Determine the appropiate PACN adjustment
value from figure 1 for the current FAT.
Combine the PACN FAT adjustment value to
the DECU hexadecimal display. Record this
value in the PAC LOG.
d.
Move the NO. 2 ENGINE CONDITION lever
to the FLT position.
e.
Repeat steps 3b thru 3d for the opposite
engine.
If the PAC value logged or the
adjusted PACN is BELOW the
established PAC trigger value during
the ground PAC, do not fly the aircraft.
If the PAC trigger value logged or
the adjusted PACN is BELOW the
established PAC trigger value during
the hover or flight PAC, abort the
mission and return the aircraft to the
maintenance facility. Troubleshoot the
engine indicating systems, inspect
engine for FOD, check PTIT thermal
couples, and check for cleanliness. If
needed, performengine compressor
wash. If the engine shows no
signs of damage and the indicating
sytems are operating correctly,
complete a MCP or MPC PAT and
establish a new trigger value IAW TM
55-1520-240-MTF.
4-22