-
APU start- APU delivers 28V/400 Amps. The battery is required
to be turned off to prevent overcharging. Two thumbs up are required from
the pilot (one to connect APU, one to spool up). APU starts should be used
when:
- Battery
has less than 17 V [NATOPS 7-12]
- Following
a Hot Start if TOT limits have not been exceeded [NATOPS HOT START EP]
- During cold weather operations (<15C) [NATOPS 17-5]
- All
starts for HT-8 unless battery is essential [Squadron SOP]
- Use of limits - The flight and engine limitations are a direct
result of the flight test programs and actual operational experience. Compliance
with these limits will allow the pilot to safely perform the assigned missions
and permit the pilot to derive maximum utilization from the helicopter.
Note - If the aircraft, rotor, or engine limitations are exceeded,
record the fact on a maintenance action form and further flight shall not
be attempted
until the aircraft is inspected by qualified maintenance personnel.
- Starter limits- Limit starter energizing time to the following:
External Power |
Battery Power |
25 sec ON / 30 sec OFF |
40 sec ON / 60 sec OFF |
25 sec ON / 30 sec OFF |
40 sec ON / 60 sec OFF |
25 sec ON / 30 min OFF* |
40 sec ON / 30 min OFF* |
*Time is less for APU starts because higher amperage spools up starter
faster and heats it up quicker.
Note - If light-off occurs within the first 20 seconds of the start sequence,
the starter may be operated for 60 seconds with a 60 second cooling period. Three
such attempts can be made in a 30 minute period, then wait 30 minutes to allow
the starter to cool. [NATOPS 4.10]
- 2C67 curriculum introduction and general information.
Differences between early TH-57B, late TH-57B
|
OLD |
NEW |
Cargo Hook |
- |
YES |
Fuel Capacity |
76 Gal |
91 Gal |
Refueling Type |
Gravity |
Gravity & Pressure (<125PSI) |
ECS |
Robs 70HP |
Freon system robs 5HP |
Duct High Temp |
- |
Sensor & Caution light |
- Student responsibilities for CPT cockpits - NA
- Use of checklists/voice reports - PRESTART CHECKLISTS
- 2C67 scheduling - NA
- Location, function, and operation of cockpit gauges, radios, switches,
and engine /rotor controls - {Be familiar w/ CPT}
- Student checkout on 2C67 operation - NA
-
RPM beep control - Nf rpm is set by the pilot using the GOV RPM
increase-decrease switch located on the collective. The switch operates an
electric linear actuator motor, which makes fine adjustments to the governor
throttle lever, 96 - 101 + 0.5%. The system is protected by
the GOV CONT C/B [NATOPS 2.1.3, Systems 2-22] {There is a lag in system,
beep then
wait for result. On the start checklist, "Twist grip Full Open Not to Exceed
40%" is a separate item from "Nf/Nr 100%", so Nf can be beeped to 100%.
All other times they are joined because Nf has already been set to 100%.}
- Abnormal starts
- Starter failure - Starter
OFF. {If Ng rose, but <15% then get APU.
No rise may indicate bad starter.}
-
Igniter failure - {Possible
igniter failure or fuel flow problem. If igniter C/B popped,
reset after EP, get APU}
IGNITER FAILURE [NATOPS 13.2]
INDICATIONS:
TOT does not
rise after twist grip rotated to FLIGHT IDLE
Ng does not
rise above 20 percent
PROCEDURES:
*1. Twist
grip Close
*2. Fuel valve
OFF
*3. Starter
Secure
*4.
BAT switch OFF (when Ng is zero) {At Ng zero, a valve opens which empties
fuel
from engine}
- Hung start
HUNG START [NATOPS 13.4]
INDICATIONS:
Ng rises slowly
and stabilizes below 50 percent
TOT rises
more slowly than normal
PROCEDURES:
*1. Twist
grip Close
*2. Fuel valve
OFF
*3. Starter
Secure After TOT Stabilizes Below 400 C
*4. BAT switch
OFF {When rotors stop for strobes}
- Hot start
HOT START [NATOPS 13.3]
INDICATIONS:
TOT exceeds
limits
TOT light
illuminates
Note - Any of the following indications, particularly when combined,
indicates an increased potential for a hot start and may necessitate an aborted
start to preclude an overtemp:
Excessive
rise in TOT
TOT accelerates
through 840 degrees
Battery voltage
stabilized below 17 volts on starter engagement
PROCEDURES:
*1. Twist
grip Close
*2. Fuel valve
OFF
*3. Starter
Secure (After TOT stabilizes at 400C or below)
*4. BAT switch
OFF {When rotors stop for strobes}
Caution - Do not allow the TOT to rise above 810 C for more than 10 seconds
or 927 C for any length of time.
Note - Utilize APU for subsequent start attempts after aborted starts
if TOT limits have not been exceeded.
- Engine fire on start
ENGINE FIRE ON GROUND (EXTERNAL) [NATOPS 13.5]
INDICATIONS:
FIRE warning
light
Smoke
Fire
Indication
from fire guard
PROCEDURES:
*1. Twist
grip Close
*2. Fuel valve
OFF
*3. BAT OFF
© *4. Rotor Brake Engage
*5. Helicopter
EXIT and use the fire bottle to extinguish the fire or get clear of the aircraft
Warning - After exiting aircraft, beware of rotor blades.
- Abort Start PROCEDURES:
*1. Twist
grip Close
*2. Starter
Secure After TOT Stabilizes Below 400 C
*3. BAT switch
OFF {When rotors stop for strobes}
- Post shutdown fire/internal - {May be a slow rise to 400, watch carefully
because there is also a rise in normal shutdown}
POSTSHUTDOWN FIRE (INTERNAL) [NATOPS 13.6]: A post shutdown fire
is an internal engine fire that occurs in an engine that is stopped or
coasting down.
INDICATIONS:
TOT rises
above 400 C
Flames or
smoke coming from engine
PROCEDURES:
*1. Starter
Engage
*2. Fuel valve
OFF
*3. Igniter
C/B Pull
*4. Starter
Secure After Fire is Extinguished
- Anti-Ice operation
Operation of the engine during icing conditions
could result in ice formation on the compressor front support. If ice were
allowed to build up, air flow to the engine would be restricted and engine
performance decreased. The engine has an anti-icing system to prevent ice formation
on the compressor front support. The anti-icing system includes an anti-icing
valve mounted at the 12 o'clock position the front face of the diffuser scroll,
two stainless steel line between the anti-icing valve and the compressor front
support, and passages within the compressor front. The pilot must turn on the
anti-icing system when encountering icing conditions. When this system is on,
hot compressor discharge air is directed to two ports on the compressor front
support. Hot air flows between the walls of the outer skin into the hollow
radial struts through the struts, and between the walls of the hub. The flow
of hot anti-icing air keeps the temperature of the compressor front support
above the freezing point of water. [NATOPS 2.1.1, Systems 2-18]
Note- Engine anti-icing will remain in the last energized position in the
event of an electrical failure.
When anti-ice switch is placed ON, TOT should rise 10-15C. When
placed OFF, TOT should drop 1-10C. [NATOPS Ch. 10, Pretakeoff checklist
(3), item I ]
{TOT rises when anti-icing system is activated because it uses
part of
the 75% compressor discharge cooling air to heat the front supports}
ICING [NATOPS 14.13]: Operation of the engine during icing
conditions could result in ice formations on the compressor front support.
If ice were
allowed to build
up, air flow to the engine would be affected and engine performance
decreased. Every effort
must be made to stay clear of known icing conditions. The
anti-icing system in this helicopter is to be used as a preventive measure
only.
Once ice has
accumulated, the anti-ice system cannot be used as a corrective
measure (will not de-ice). Intentional flight into any known icing
conditions (<4
C in visible moisture) is prohibited. For inadvertent
flight in icing conditions:
PROCEDURES:
1. Eng anti-icing
ON
2. Pitot Heat
switches Heat
©3. Alternate static port
As req.
If unable to remain clear of icing
conditions:
4. Land as
soon as possible
Warning: Monitor engine instruments and be prepared for partial or complete
power loss
When the OAT is below 10 C and flight into visible moisture is likely,
anti-icing and pitot heat shall be on. [RWOP 1012]
SUMMARY:
Flight
into icing conditions is prohibited (<4C w/ visible moisture} [NATOPS
ICING EP]
Anti-Icing
shall be checked in Prestart if below 10 C [NATOPS 7-14]
Anti-Icing
shall be on if: Below 10C and visible moisture [RWOP 1012]
5 min after
engine wash for maximum drying [NATOPS 7-14]
Anti-icing
is preventive only
When placing
Anti-icing on check for rise in TOT
- Normal starting/shutdown procedures - PRESTART
CHECKLISTS
- FAM stage communication procedures - PRESTART
CHECKLISTS
- FAM stage checklists - PRESTART CHECKLISTS
(none)
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