Limits Flashcards
Exceeding Operating Limitations
Anytime an operational limit is exceeded, an appropriate entry shall be made on a MAF. The entry shall state what limits were exceeded and include range, duration, and any additional information that would aid maintenance personnel.
The flight display’s digital readout will display XXX in red when a torque or TGT limit is exceeded.
If a limit is exceeded to the extent that a red XXX is flashing, the crew shall land as soon as practicable.
Engine Limitations
The engines are limited by Ng, Np, TGT, oil px and oil temp. Specified temperature limitations ensure that engines are operated at internal temperatures that will not shorten the service life expectancy of engine components.
Engine Starter Limitations
A start cycle is defined as starter initiation, acceleration of the output drive, and starter dropout. A 60 second delay between start attempts is required any time a start is aborted, except during emergencies.
Engine Start Limitations
- The single and dual engine start envelopes are presented in figure 4-3. For crossbreed starts, the receiving engine shall be at or above 24% Ng prior to advancing PCL to idle.
- Engine start with the main rotor blades or tail rotor pylon folded is prohibited.
- The start TGT limit is 851 deg C until idle speed is attained
Engine idle limitations with gust lock engaged
Engine operation with gust lock engaged is prohibited
TGT
0-810 continuous green 810-851 30 min yellow 851-878 2.5 min (10 min for max power and limiter checks only) red 878-903 2.5 min red 903-949 12 sec red 949 max red
Np
<96% avoid red 96 to 105% continuous green (yellow above 101%) 105 to 117% 20 sec yellow 117 to 120% 12 sec yellow 120% max red
CAUTION
during engagement, extended operations in the 20 to 40% and 60 to 75% ranges may cause engine damage
Nr
<96% avoid red 96-101% continuous green 101 to 120% precautionary yellow 120% max red >120% max for FCF only, red 127% overspend latch red
Dual engine torque <80 KIAS
0 to 120% continuous green
120 to 144% 10 sec yellow
144% max red
Dual engine torque >80 KIAS
0 to 106% continuous green
106 to 127% 10 sec yellow
127% max red
NOTE
dual engine tq limits apply when both engines are above 65% tq
Single engine torque
0 to 135% continuous green
135 to 144% 10 sec red
144% max red
Ng
0-102.2% continuous green
>102.2-106% 2.5 min yellow
>106-107% 12 sec red
107% max red
XMSN Temperature
-50 to 105 continuous green
105 to 120 precautionary yellow
120 max red
XMSN Pressure
20 psi min red 20 to 30 psi idle and transient yellow 30 to 65 psi (45 to 60 psi in level flight) continuous green 65 to 130 psi precautionary yellow 130 psi max red
Engine oil temperature
-50 to 135 continuous green
135 to 150 30 min yellow
150 max red
Engine oil pressure
22 psi minimum red 22 to 26 psi precautionary yellow 26 to 100 psi continuous green 100 to 120 psi precautionary yellow 120 psi max red
Engine Start Cycle
<16 deg 3x60sec, 1x30 min
16 to 52 deg, 60 sec, 30 min
Engine Motor (ignition off)
Any temp - 2 min on, 5 off; 2 min on, 30 min off
NOTE
- A start cycle is defined as starter initiation, acceleration and dropout
- Times for motoring are cumulative within a 5 min period
Minimum planned fuel on landing
Minimum planned fuel on landing shall be no less than 600 pounds
APU Limitations
The APU is no intended for routine in flight use. Operation of the APU in flight shall be limited to essential operations only. Acceptable in flight use includes emergency procedures, single engine training, practice autorotations, and powering the ECS during extreme temperature operations.
ORM Process
- Identify Hazards
- Assess Hazards
- Make Risk Decisions
- Implement Controls
- Supervise and watch for change
