ENG 1 FAIL or ENG 2 FAIL.
The ENG 1 or ENG 2 FAIL caution is illuminated whenev-
er the engine failure logic within the DECU recognizes
any of the following:
1. Power turbine shaft failure. N2 is greater
than RRPM by more than 3%.
2. N1 underspeed.
3. Engine flameout.
4. Over temperature start abort (Primary
5. Primary system fail freeze (Primary and
Reversionary mode hard faults, FADEC
caution is illuminated).
6. During normal shutdown as the N1 rpm
goes below 48% the ENG 1 FAIL or ENG 2
FAIL caution is illuminated and then turned
off 12 seconds after the N1 rpm drops below
9-1-13. Single Engine Failure Low Altitude/Low
Airspeed and Cruise.
If an engine fails under conditions that will permit S/E
flight, thrust and 712 engine beep trim must be adjusted
as required to maintain safe RRPM. Initial thrust reduc-
tion will vary from no reduction at zero airspeed below 20
feet to a significant reduction at higher altitudes and air-
speeds. Attempt to maintainat least 96 percent RRPM.
If the helicopter is below the best S/E climb airspeed,
forward cyclic must be applied to attain a nose-low attitu-
de of up to 30_ in order to gain airspeed. As airspeed
increases to 30 knots, adjust the pitch attitude of the
aircraft to accelerate to the best S/E airspeed.
If an engine fails under conditions that will not permit S/E
flight, the procedures will be essentially the same as for
continued flight, except that cyclic pressures are applied
to decelerate the helicopter for touchdown, rather than
continued acceleration. During deceleration, just prior to
touchdown, avoid rotating the aft landing gear into the
Continued flight is possible:
1. Thrust control Adjust as necessary to
ENGINE BEEP TRIM switch RPM
INCREASE as required.
3. External cargo Jettison (if required).
4. ALT switch Disengage.
5. Land as soon as practible.
If S/E flight can be maintained, an attempt to
restart the inoperative engine may be made if
there is no evidence of fire or obvious me-
Continued flight is not possible:
Land as soon as possible.
9-1-14. Engine Restart During Flight.
Fire detector and extinguishing systems
are not provided for the APU. Crewman
must monitor APU area for fire.
If abnormal indications are present during
the restart, shut down the engine immediate-
1. APU Start.
ENG COND lever (inoperative en-
ENG COND lever (inoperative en-
gine) STOP, then GND.
4. FIRE PULL handle In.
5. All FUEL PUMP switches ON.
6. XFEED switch As required.
7. Starting engine Perform.
8. APU OFF.
Normal Engine Beep Trm System
Failure (High Side) or N2 Governor Failure.
Failure of the normal engine beep trim system to the high
side may be recognized by increasing torque on the af-
fected engine, decreasing torque on the unaffected en-
gine, an increase in RRPM, and a lack of response of
normal engine beep trim. These indications should be
confirmed by observing all the engine instruments.
Controling RRPM with the ECL must be done smoothly
and with care. Engine response is much faster and it is
possible to cause the RRPM to exceed limitations or
decrease to the point that the generators will be discon-
nected from the buses. If the thrust control is moved, it is
necessary to control RRPM with the engine condition
lever and the No.1 and 2 ENGINE BEEP TRIM switch. If
a malfunction to the high side occurs, perform the follow-
1. Thrust control Adjust as required to
maintain RRPM within limits.