5-2. POWER CHECK CHART - ROLLS ROYCE 250-C20W ENGINE
The power check chart (Fig. 5-7) shows the relationship of engine
torque and turbine outlet temperature, at various conditions of
pressure altitude and OAT for a Rolls Royce 250-C20W engine
producing specification power as installed in the 330 helicopter. The
primary purpose of this chart is for use as an engine performance
trending tool to aid in determining if the engine is producing
specification power, or if engine power deterioration has occurred.
NOTE: Power check data taken at regular intervals should be plot-
ted to monitor trends in engine condition. See Rolls Royce Opera-
tion and Maintenance Manual for additional information on trend
analysis.
The power check chart is based on the following conditions:
91% N
2
Cabin heat , defrost and engine anti-ice OFF.
Aircraft in cruise attitude.
10 amperes electrical load
NOTE: Operation of alternate air door does not affect this data
Use of chart:
The primary use of the chart is illustrated by the EXAMPLE (page
5-11) and by the sample arrows shown on the power check chart. To
determine power check values, it is necessary to read and record en-
gine TORQUE PRESSURE, TURBINE OUTLET TEMPERA-
TURE, PRESSURE ALTITUDE, and OAT while the helicopter is
flown in level flight at 91% N
2
.
Figure 5-7, Power Check Chart valid for external plenum inlet
screen only.
For aircraft configured with internal plenum inlet screen see
Figure 5-8.
Performance
Pilot's Flight Manual
Schweizer RSG, LLC.
Model
269D
Helicopter
5-8
Reissued:
16
Jan 2019
FAA Approved
Book 3.indd 132
8/4/19 1:25 PM
