- Limitations - LIMITATIONS
SHEET
- Cold Weather Limitations
[NATOPS
17.4] Cold weather presents no serious problems
for flight if pilot uses necessary precautions, especially in preflight.
- Servicing - Should be accomplished
immediately after shutdown to prevent condensation within
the tanks because of temperature change.
- Preflight - All vents and opening
must be checked for ice. Snow, shush ice shall be removed. Pilot must
be more thorough in the preflight inspection when temperatures have
been or are below 0°C (32°F).
- Preparation for Flight – All
vent openings such as fuel vents, battery vents, transmission breather,
heater exhaust / intake, and engine air intakes must be checked for
ice. WARNING: Takeoff is prohibited with show or ice on the helicopter
due to potentially large differences in CG.
- Preheating - If controls are difficult
to move, it is advisable to preheat them. Flight and engine controls
may be difficult to move after the helicopter has been cold soaked.
If the controls are
not sufficiently free for a safe start and low power warm-up, have
the affected controls thawed by heating. It may also be advisable
to apply preheating to other areas such as engines, transmissions,
and main rotor hub, and cockpit. NOTE: Extremely unequal temperature
differences between the cockpit and OAT can cause canopy to crack.
- Prestart - APU should be used
to prevent a hot start. Avoid starting engines on glare ice to prevent
movement of aircraft due to torque effect. Battery starts below –15°C
(-5°F) are marginal. A sudden loss of oil pressure in cold weather,
other than a drop caused by relief valve opening, is usually because
of a broken oil
line. Shut down and investigate for cause.
- Takeoff - Restricted visibility
may occur from blowing snow which may require max power takeoff
or instrument takeoff without hover. Disorientation is possible, use
visual cues.
- In Flight - If icing occurs, use
pitot heat, defogger, and engine anti-icing. Windshield
may become iced over. One per revolution vibrations from ice shedding
may occur. Increase of torque
may be necessary. Intentional flight in any known icing condition
(<4°C in visible moisture) is prohibited. If icing condition
are encountered during flight, effort should be made to vacate the
icing environment immediately. Because of the possibility of engine
flameout, flight in falling or blowing snow is prohibited. If icing
conditions become unavoidable turn on the pitot heat, windshield
defogger, and the engine anti-ice system
- Landing - Pilot should become
familiar with terrain under snow. Visibility may be limited,
use references. Be ready to take off immediately if landing gear gets
caught. Do not reduce
Nr until helicopter will not settle
- Taxi - Use a higher taxi altitude
to prevent "white-out", zero visibility from blowing snow.
Warning - Takeoff is prohibited with snow or ice on
the helicopter. Accumulations of snow and ice will be removed prior to
flight. Failure to do so can result in hazardous flight because of aerodynamic
and center-of-gravity disturbances as well as the introduction of snow, water,
and ice into internal moving parts and electrical systems. The pilot should
be particularly attentive to the main and tail rotor systems and their exposed
control linkages.
Note - When moving the helicopter into or out of a heated
hangar where there is an extreme difference in outside temperature, a canopy
door should be open slightly to equalize the temperature inside the cockpit.
Extremely unequal temperatures on opposite sides of Plexiglas can cause differential
contraction and breakage.
Caution - Whenever possible, avoid starting engines on glare
ice to avoid the effect of torque reaction when increasing rpm.
Note -Battery starts below minus 15° C
(-5° F) are marginal.
Caution - Should the engine fail to accelerate to proper
idle speed (cold hang-up) or the time from lightoff to idle is excessive, abort
start.
Warning - Intentional flight
in any known icing condition (less than 40C in visible moisture)
is prohibited. If icing conditions are encountered during
flight, effort should be made to vacate the icing environment
immediately.
Warning - Because of the possibility of engine flameout,
flight in falling or blowing snow is prohibited.
Warning - Control activity cannot be depended upon to remove
ice from the main rotor system. Vigorous control movements should not be made
in an attempt to reduce low-frequency vibrations caused by asymmetrical shedding
of ice from the main rotor blades. These movements may induce a more asymmetri-cal
shedding of ice, further aggravating helicopter
vibration levels.
Note- If the windshield defogger fails to keep the windshield
clear of ice, the side windows may be used for visual reference
during landing.
Warning - Ice shed from the rotor blades and/or other rotating
components presents a hazard to personnel during landing and shutdown. Ground
personnel should remain well clear of the helicopter during landing and shutdown
and passengers/ crewmembers should not exit the aircraft until the rotor has
stopped turning.
Warning - If visual reference is lost, accomplish
a waveoff.
Caution - Whenever possible when landing on glare ice, reduce
sink rate as much as practical in order to reduce bending loads
on the crosstubes.
Caution - Radio and radar waves can penetrate the surface
of snow and ice fields (such as the polar region); therefore, when radio and
radar equipment are used for measuring terrain clearance, they may indicate
greater terrain clearance than actually exists.
Caution - Exercise extreme caution when starting and/or
stopping rotors on ice- and snow -covered surfaces to prevent the helicopter
from sliding.
LIMITATIONS:
Voltmeter increases up to 28.5V +/- .5
@ OAT < 0 C [NATOPS
4-6]
Do not wash at or below 5C [NATOPS
7-11]
In temperatures below 7C,
twist grip may be opened at 13% Ng [NATOPS 7-12]
To prevent icing, use 10 min warm-up at IDLE when aircraft cold
soaks in <-12C and high humidity [NATOPS
7-12]
Temporary start conditions of 150 psi engine oil and 70 psi transmission
oil are allowable [NATOPS 7-13]
Anti-icing must be checked in prestart < 10C [NATOPS
7-14]
Anti-icing and pitot heat must be on <10 w/ visible moisture
likely [RWOP 1012]
Low level BI shall not be conducted over when water when <60F [RWOP
1012]
-
Power Source for all cockpit gauges
28V DC |
Self-driven |
Wet Line |
Air Pressure |
Other |
Voltmeter
Loadmeter
Att Gyro
TOT
RMI
HSI
Eng Oil Temp
Radar Altimeter
Xmissn Oil Temp
Fuel Quantity
Turn Needle
Fuel Pressure |
Nf - Tach/Gen
Ng - Tach/Gen
Nr - Tach/Gen |
Eng Oil Pressure
Xmissn Oil Press
Torque- & DC |
Airspeed - Pitot/Static
Altimeter - Static
VSI - Static |
Clock - Spring wound
Ball - Gravity
|
- Single instrument indications - Involve engine performance
instruments and caution and warning lights. Pilot should consider each
flight instrument and ask what would be the appropriate action if it
fell to zero, or exceeds normal or maximum operating limits. [FTI
6-3] If redundant or related systems exist be sure to check to
see if they agree and if not determine which is in error.
- Ng / Tach / TOT - If either falls to “0” or
does not rise and fall with power changes while other gauges appear
normal:
- Monitor other engine instruments
- Avoid high Power settings
- Land as soon as Practical
Note: Failure of the Ng tach generator
is usually accompanied by the engine out horn and caution
light
- Torque meter – If it falls to “0” independently,
the wet line has most likely ruptured:
- Monitor ENG OIL PRESS
- Land as soon as possible
Note: Minor Fluctuations are normal
- ENG / XMSN Oil PRESSURE -
If either indicates outside of normal range or fluctuates erratically:
- Land as soon as possible
Note: XMSN malfunctions require minimal PWR changes
to minimize changes to xmsn torque.
- ENG / XMSN Oil TEMPERATURE -
- If either redlines:
Land as soon as possible.
- If either fluctuates or falls to “0”: Land as soon
as practical.
-
In-flight malfunctions - Emergencies fall into two
categories, those that require immediate pilot attention and those
that do not. Any loss of power, control, or structural integrity
requires immediate action; most others are non-critical.
NATOPS EPs generally
divided into three categories:
- Maintaining/regaining power available
- Maintaining/regaining Nr, cyclic control, rotor control
- Minimizing
damage and getting on deck. If the situation is not critical, it may
become so requiring action soon, or be a "system
failure", which may be noted and acted on as required. [FTI
6-2]
Always scan Nr first during any emergency.
- Land as soon as Practicable – Extended flight
is not recommended. The landing site and duration of flight is at the discretion
of PIC. (Land at the nearest aerodrome, passing an aerodrome is considered
extending flight)
- Land as soon as Possible – Land at the first site at which a safe
landing can be made. (i.e. Farm field, parking lot etc.)
- Land Immediately – Landing in trees, water, or otherwise unsafe
areas should be considered as a last resort.
PROCEDURES: [ADAPTED FTI 6-3] Procedure
when malfunction occurs:
- Correctly identify the emergency condition
- Report to the instructor this is a Land as Soon as Possible / Practical
and your intended landing Site.
- Begin approach to nearest applicable site.
- Recite EP steps and remind Copilot to break out the PCL
- Remind Copilot of his responsibility to transmit Pan / Mayday report
and complete the landing checklist
(none for this event)
- Blindfold cockpit check
Caution Light Panel: (Left to Right)
- AUD/MUT
Switch, Fire DET Test Button, Caution Lights, Caution Lt Test
button, Clear Chip Button
- Gauges Instrument Panel: (6 Columns, Top to Bottom)
Column
1 - Voltmeter
Column
2 - Engine Oil Pressure and Temp, Xmissn Oil Press, Loadmeter/Fuel
Press.
Column
3 - Torquemeter, TOT, Ng Tach, Clock
Column
4 - Airspeed Ind., Nf/Nr Tach, Radar Alt
Column
5 - Attitude Gyro, HSI, RMI
Column
6 - BAR Altimeter, VSI, Turn Needle/Ball
- Avionics Instrument Panel: (Top to Bottom)
Transponder, VHF Radio/NAV, UHF Radio
- Lower Instrument Panel:
(Forward to Back)
Caution/Icing/Hydraulic Switch Panel, Avionics
Selector Switch Panel (right seat), Avionics Selector Switch
Panel (left seat) Environmental Control Panel, Lower Circuit Breaker, RMI Slaving
Switches
- Collective Switch Box: (From Left to Right)
Starter Switch, Search Light Switch/Control
Hat, Governor RPM Switch, (Idle Release Button below
Switch Box above Twist Grip)
- Overhead CS Panel and Switches: (Forward to Aft, Left
to Right)
1st Row - Landing
Light Switch, Pitot Heat Switch, Defog Blower Switch, Battery Switch,
Generator Switch
2nd Row - Steady/Flash
Switch, Dim/Bright Switch. Gen Field CB, Gen Reset CB, Attitude
Ind CB.
3rd Row -Position
Light Switch, Inst Lt Rheostat, Anti Coll Lt Switch (seven rows
of various CB's)
- Miscellaneous:
Wet
Compass - Mounted directly fwd of right door at knee
level
Cabin
Heat Valve - To the right of overhead CB panel
Cyclic
Friction Adjustment Knob - Base of cyclic
Collective
Friction Adjustment Knob - Base of collective
OAT
- Upper middle windscreen
Fuel
Valve - Directly below RMI gauge
TOT
Indicator Test - Below Voltmeter
Force
Trim Buttons - On cyclic, under normal thumb position
Cargo
Release Button - On cyclic, high thumb position
Cockpit
Lts - Mounted high on center column
First
Aid Kit - Mounted behind center column
Aud
Speaker - Overhead, behind CB's
.
- Abnormal starts - (see CPT1)
.
- Emergency engine shutdown:
EMERGENCY SHUTDOWN [NATOPS 13.1]
Following any emergency that necessitates rapid crew egress, execute a shutdown
as follows:
1. Twist grip OFF
2. Fuel valve OFF
3. BAT switch OFF
© 4. Rotor brake OFF
- Engine oil system malfunctions
-
ENGINE or TRANSMISSION OIL PRESSURES [NATOPS 14.28.3]
ON GROUND:
» If transmission oil pressure is 50-70 PSI or engine oil pressure
is 130-150 PSI, do not accelerate the engine above
flight idle until the transmission and engine oil pressures are within
normal limits.
» The engine shall be shut down if he transmission oil pressure
exceeds 70 PSI or engine oil pressure exceeds 150 PSI
AIRBORNE:
» If either pressure gauge does not indicate within normal range or fluctuates
erratically:
- Land as soon as possible
WARNING
With suspected transmission malfunctions,
the pilot should make an approach with minimum power changes
to transmission torque.
Note - Check the transmission oil pressure with
the twist grip full open. Illumination of the TRANS OIL PRESS caution
light is common, while the twist grip is at flight idle, after power
off maneuvers. However, the gauge should indicate positive transmission
oil pressure.
- ENGINE or TRANSMISSION OIL TEMPERATURES [NATOPS
14.28.4]
If either oil temperature gauge indicator exceeds red line limitations:
*1. Land as soon as possible
If either oil temperature gauge fluctuates or falls to zero:
*2. Land as soon as practical
- Transmission oil system malfunctions - See engine
oil system malfunctions above.
- Tach/Gen malfunctions - {Check other tach/gen. For
Nr, check Xmssn oil press/Hydraulic Press -driven by same shaft}
Nr AND Nf TACHOMETER MALFUNCTION [NATOPS 14.29.1]
If the tachometer indications fluctuate or erratically peg
and all other instrument and lights are normal, land as soon as practical,
utilizing the remaining engine and performance instruments to monitor flight
performance.
- TOT malfunction - {No Ng - check other tach/gen.
Look for loss of Eng oil press because pump is on same shaft}
Ng TACHOMETER or TURBINE OUTLET TEMPERATURE SYSTEM [NATOPS
14.28.1]
If Ng or TOT falls to zero or fails to rise and fall with corresponding
power changes:
- Monitor other engine
instruments
- Avoid high power
settings
- Land as soon as
practical
Note- Failure of the Ng tachometer generator is usually accompanied
by actuation of the engine out warning horn and light.
- OVERTORQUE/OVERTEMP/OVERSPEED [NATOPS
14.32]
If any overtorque/overtemp/overspeed is observed, land as soon
as possible.
- Torque Malfunctions
TORQUEMETER [NATOPS
14.28.2]
If the torquemeter falls to zero, it is probable that the torque
line has ruptured. Loss of engine oil will be kept to a minimum by a restrictor
fitting in the system.
*1. Monitor engine
instruments
*2. Land as soon as
possible {Wet line malfunctions are land as soon as possible}
If the digital torquemeter indication is unusually low or falls
to zero with a corresponding digital readout, it is probable that the torque
line has ruptures:
*1. Monitor engine
instruments
*2. Land as soon as
possible
The digital torquemeter incorporates a transducer between the
wet line and the gauge. If the indicator falls to zero and the digital readout
is extinguished, the cause is a loss of electrical power to the indicator.
1. Monitor engine
instruments
2. Check TRQ circuit
breaker In {Bottom panel, right}
3. Land as soon as
practicable {Electrical, not wet line, so it is practical}
Note- Some minor
torque fluctuation is normal and should not be cause for concern
- Post shutdown fire/internal - (see CPT1)
- Smoke and fume elimination
SMOKE AND FUME ELIMINATION [NATOPS
14.17]
Indications: Fumes in cockpit, Smoke in cockpit, Equipment
Failure
1. ECS and DEFOG
blower OFF
2. Vents/windows
Open
3. Slip or skid aircraft
to eliminate smoke and fumes
4. Land as soon as
possible
- Suspected fuel leakage
SUSPECTED FUEL LEAKAGE [NATOPS 14.10]
Indications:
Unusual fuel usage,
Fuel fumes in cockpit
1. Transmit position
and intentions
2. Unnecessary electrical
equipment Secure {In VFR, battery and gen OFF since call made.}
3. Land as soon as
possible
When on deck:
4. Shutdown Completed
5. Helicopter Exit
- All FAM stage checklists and voice reports - PRESTART
CHECKLISTS
- Normal starting/shutdown procedures - PRESTART
CHECKLISTS
- Anti-ice operation - same as from CPT1
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