Autorotation Landing Procedure following Engine Failure
- Lower collective.
- Monitor and control rotor rpm.
- Establish approximately 65 kt airspeed.
- Move the fuel flow control to the shutdown position.
-Re-light the engine if possible.
. Otherwise : close the fuel shut-off valve.
switch off : the booster pumps, generator.
electrical power master “ALL-OFF” switch
(if smell of burning).
. Maneuver, to head the helicopter into the wind in final approach.
. At a height of approximately 65 ft, flare. - At height 20-25 ft and at constant attitude, gradually apply
collective pitch to reduce the sink-rate. - Resume level attitude before touch-down, and cancel any side-slip
tendency. - Gently reduce collective pitch after touch-down.
Landing after Engine Failure in Hover IGE
- Do not reduce collective.
- Control yaw.
- Cushion touch-down by increasing collective pitch.
- Reduce collective pitch as soon as the aircraft is on the ground.
Landing after Engine Failure in Hover OGE
- Reduce collective pitch.
- Apply forward cyclic pitch to gain air speed according to available
height. - Autorotation landing.
Engine Relight in Flight
Normal relighting ceiling is 13000 ft; relighting may
be attempted throughout the altitude envelope.
Proceed as outlined below :
- Booster pumps - - - - - - On
- Ng below 30%; normal starting
procedure.
To avoid jerk on re-synchronization, accelerate the engine progressively, when free turbine speed approaches rotor speed.
Large Drop in Fuel Flow Rate
Same symptoms as for complete engine failure but after a few seconds, Ng
stabilizes at a low rpm value (less than 70 %).
. Establish autorotation IAS 65 kt, then advance the fuel
flow control into the emergency sector. Ng and t4 should rise.
. Control engine speed to 70 % Ng.
. If necessary, increase collective pitch to bring rotor speed to
350 rpm.
. Increase fuel flow until rotor speed is approximately 380 rpm.
. Trim collective pitch and fuel flow control to hold level flight at
this rotor speed.
Excessive Fuel Flow Rate
Ng, t4, NR and torque increase
. Do not reduce collective pitch.
. Reduce fuel flow until rotor speed corresponds to a position of
the indicator pointer in the centre of the green area.
. Continue flight with the governor out of action. Any reduction of
collective pitch will cause an increase in rotor speed which must be
counteracted by adjusting the fuel flow control position.
NOTE: The landing approach should be made along a low gradient path, at 65 kt, holding the rotor speed at the upper limit of the green area (394 rpm) using the fuel flow control. On final approach, reduce forward speed without touching the fuel flow control. The rotor speed will drop when the collective pitch is increased on touchdown. After touchdown, reduce the fuel flow control setting before
decreasing the collective pitch.
Surging
Surging is evidenced by hunting of the rpm, torque and t4 indications
and jerks in the yaw axis.
. Reduce the collective pitch setting.
NOTE: If surging persists while fuel pressure and engine oil pressure are
correct, reduce fuel flow slightly to leave the governed range.
If surging still persists, LAND AS SOON AS POSSIBLE and shut down
the engine if there is a tendency to divergence
Fire during Engine Start
- Close the fuel shut-off valve and apply the rotor brake if necessary.
- Switch off the booster pumps.
- Crank the engine for 10 seconds, then switch off the battery.
- Use the nearby extinguishers to fight the fire.
Fire in Flight
- Enter autorotation.
- Close the fuel shut-off valve to shut down the engine.
- Switch off the booster pumps, and generator.
- Switch off the electrical master “ALL OFF” switch if there is a smell
of burning.
SMOKE IN THE CABIN
If Source of Smoke is identified
- Shut off the corresponding system.
- If necessary, use the fire extinguisher*.
- Air the cabin by opening :
. The front ventilator
. The ventilation ports
. The bad weather windows.
CONTINUE FLIGHT depending on system failed.
SMOKE IN THE CABIN
If source of Smoke is not identified
-Heating & Demisting off
If the smoke does not clear :
- Master electrical switch off.
- When the smell of smoke has disappeared, set all switches to “OFF”.
- Battery on.
- Master electrical on.
- Generator on, check voltage and amps.
- Everything normal, turn systems on one by one until the malfunction is identified.
Failure of the Tail Rotor in Hover or at Low Speed
- IGE: Bring the aircraft to the ground by reducing collective
pitch before the yaw rate is too high. - OGE: Reduce collective pitch moderately, to reduce yaw torque,
and simultaneously start to increase speed.
Tail rotor Failure in Forward Flight
- In forward flight reduce the power as much as possible and maintain
forward speed (weathercock effect), select a suitable landing area
for a steep approach at a power enabling a reasonably coordinated
flight. - On final approach, shut down the engine and make an autorotative
landing at the lowest possible speed.
Tail Rotor Control Failure in Flight
- Set IAS 70 kt in level flight.
- Press the HYD TEST button. After 5 seconds, turn the test button to the normal position.
- Make a shallow approach to a clear landing area with a slight side slip to the left. Perform a run-on landing ; the side slip will be reduced progressively as power is applied.
NOTE : Landing is made easier with a RH wind component.
SERVO TRANSPARENCY
Self-correcting, the phenomenon will induce an un-commanded right cyclic
load and an associated collective down reaction. However, even if the
transparency feedback loads are controllable, immediate action is required
to relieve the feedback loads:
- Reduce the severity of the maneuver,
- Follow the aircraft’s natural reaction,
- let the collective pitch decrease naturally (avoid low pitch) and
smoothly counteract the right cyclic motion.
Transparency will disappear as soon as excessive loads are relieved.
No fuel pressure
Failure is confirmed by illumination of the FUEL P. light
If failure is not confirmed, the faulty item is the fuel pressure gauge :
Flight may be continued.
Low fuel pressure
Failure is confirmed by illumination of the F.FILT. light
If failure is not confirmed, the faulty item is the fuel pressure gauge :
Flight may be continued.
Low Engine Oil pressure “Gauge pointer in red arc for Ng above 85 %”
Test Warning-Caution-Advisory Panel and check ENG. P. light
illuminates.
- Light does not illuminate when tested:
. If torquemeter reading is much too low:
shut down engine and make an autorotation landing.
. If torquemeter reading is correct:
LAND AS SOON AS POSSIBLE. - Light illuminates when tested:
. If torquemeter reading is much too low
LAND AS SOON AS POSSIBLE.
. If torquemeter reading is correct
LAND AS SOON AS PRACTICABLE, monitor ENG. P. light.
Engine Oil Temperature higher than Maximum specified
At Low Speed or in Hovering
- Land if possible.
. Stop the engine.
. Check that the cooler fan operates.
- If landing impossible :
. Increase speed and reduce power.
. Fly at approximately 80 kt.
The temperature should fall rapidly.
If this result is not obtained, LAND AS SOON AS POSSIBLE.
In Cruising Flight
Reduce power ; then proceed as prescribed above.
∆Ng Indicator Failure
In the event of an indicator failure, do not exceed the maximum
authorized torque value, and keep the t4 temperature below the following
limits :
| Below 15°C - 730°C
| Above 15°C - 750°C
OAT |T4 limit
Torquemeter Failure
In the event of a torquemeter failure, do not allow the engine speed to
rise above following Ng limits in the table
t4 Indicator Failure
- Comply with the Ng limitations.
- Do not attempt to start the engine.
NR/Nf readings below green arc
- NF and NR values agree
. Excessive power demand : reduce collective pitch.
Indicator reading should rise to governed value.
. Governor failure.
Different NR/Nf readings
- NR reading exceeds NF
. NR reading is incorrect. - NF reading exceeds NR
. On the ground during the starting sequence : reduce the engine fuel
flow control setting to check for possible freewheel slippage.
. In flight : NR reading is probably incorrect .
