TH-57B/C Limits Flashcards
Minimum Nf RPM
97%
Maximum Nf RPM
100%
Nf Avoid Range for Steady State Operation
71 - 88% Nf
Steady-State is defined as not remaining at Nf speed of more than one second duration
Nf overspeeds are determined on a sliding scale depending on ____, ____, and ____.
- Turbine Outlet Temperature (TOT)
- Nf percentage
- Duration
Idle Range Ng RPM
62 ± 2% Ng
Normal Range Ng RPM
60 - 105% Ng
Max Transient Ng % RPM
106% for 15secs
Engine Oil Pressure
Depending on the Ng Range
- 50psi (minimum) when Ng is below 79%
- 90psi (minimum) when Ng is 79 - 94%
- 115psi (minimum) when Ng is above 94%
Max Engine Oil Pressure
130psi
Transient Max Engine Oil Pressure Following Cold WX Start
150psi
Engine Oil Temperature
0° - 107°C
Rotor Engagement/Disengagement Wind Limits - Headwind
40kts max
Rotor Engagement/Disengagement Wind Limits - Crosswind
25kts max
Crosswind is considered 45° foreward/aft of abeam
Rotor Engagement/Disengagement Wind Limits - Tailwind
17kts max
TOT Limits During Start
- Up to 810°C with no time limit
- Between 810° - 927°C for 10secs
- 927°C Maximum
TOT Limits During Transient Power
- Up to 738°C with no time limit
- Between 738° - 810°C for 5mins
- Between 810° - 843°C for 6secs
- 843° Maximum
Minimum Fuel Reserve Requirement
10 gallons
Nr Power On Minimum
97%
Nr Power On Maximum
100%
Nr Power Off Normal Operating Range
90 - 107% Nr
At what Nr continuous operating range would there be isolation mount damage?
50 - 60% Nr
Minimum Transmission Oil Pressure
30psi
Maximum Transmission Oil Pressure
70psi
Continuous Operation Range for Transmission Oil Pressure
30 - 50psi
Transmission Oil Temperature
15° - 110°C
Max Continuous Torque
85%
Military Power (Torque)
85-100% TRQ for 5mins
Transient Torque
100 - 110% TRQ for 5secs
Fuel Pressure
4 - 30psi
What is the limiting factor on the standby generator?
Prolonged operations (when it is the primary power supply to the Essential No. 1 bus) is prohibited at speeds below 65 KIAS
When and at what Nr percent should rotor brakes be applied?
During normal operations, the rotor brake should be applied between 38 - 30%
Application of the rotor brake below what Nr percent may cause damage to the drivetrain?
30% Nr
Starter Limits (External Power)
- 25 seconds - ON
- 30 seconds - OFF
- 25 seconds - On
- 30 seconds - OFF
- 25 seconds - ON
- 30 mins - OFF
Three attempted starts with a 30min cooldown after the last attempted start
Starter Limits (Battery)
- 40 seconds - ON
- 60 seconds - OFF
- 40 seconds - On
- 60 seconds - OFF
- 40 seconds - ON
- 30 mins - OFF
Three attempted starts with a 30min cooldown after the last attempted start
If light-off occurs within the first ____ seconds of the start sequence, the starter may be
operated for ____ seconds with a _______-__________ cooling period. Three such attempts
can be made in a ____- minute period, then wait ____ minutes to allow the starter to
cool.
- Light-off occurs within the first 20 seconds
- Operated for 60sec with a 60sec cooling period
- Made in a 30min period then wait 30mins
Max Internal Gross Weight
3200 lbs
Max Gross Weight Including External Cargo
3350 lbs
Acceleration Limits
Positive 2.5 to 0.5 G’s
At max gross weight
Airspeed Limits (0-1000’ DA)
- Max Sidewards: 25kts
- Max Rearward: 15kts
Airspeed Limits (1000 - 2000’ DA)
- Max Sidewards: 20kts
- Max Rearward: 15kts
Airspeed Limits (2000 - 4000’ DA)
- Max Sidewards: 15kts
- Max Rearward: 15kts
Airspeed Limits (4000 - 6000’ DA)
- Max Sidewards: 10kts
- Max Rearward: 10kts
Airspeed Limits (6000- 10,000’ DA)
- Max Sidewards: 5kts
- Max Rearward: 5kts
Max Rate of Climb Airspeed
50 KIAS
Minimum IFR Speed
65 KIAS
Max Airspeed With Any Combination of Doors Off
110 KIAS
Max Autorotational Airspeed
100 KIAS
Turbulence Penetration Speed
80 KIAS
Altitude Limitations (FCS OFF)
If Gross Weight = less than 3000lbs:
* 20,000’ (Pressure Altitude)
* 18,000’ (Density Altitude)
If Gross Weight = more than 3000lbs:
* 16,000’ (Pressure Altitude)
* 13,000’ (Density Altitude)
Altitude Limitations (FCS ON or IFR)
If Gross Weight = less than 3000lbs:
* 11,500’ (Pressure Altitude)
* 13,500’ (Density Altitude)
If Gross Weight = more than 3000lbs:
* 8,500’ (Pressure Altitude)
* 11,000’ (Density Altitude)
Max Climb and Descent Rates in IFR
1000 fpm
Center of Gravity Limit (FCS ON)
From station 106.75 to 112.5
Center of Gravity Limit (FCS OFF)
From station 106.0 to 114.2
Center of Gravity Limit (Front Doors Removed)
From station 106.0 to 110.0
Prohibited Operations
- TH-57B - Operating in IMC/Icing conditions
- TH-57C - Operating in icing conditions
- IFR operations with any doors removed or external load
- Asymmetrical doors-off flight
Prohibited Maneuvers
- Aerobatic maneuvers
- Protracted operations in the AVOID and CAUTION areas of the height-velocity diagram
- Fully developed vortex ring state
- Intentional entry into blade stall
- Hovering turns more than 45° per second
Required Equipment for Night Flight
- All instrument and circuit breaker panel lights
- All exterior lights
- Operable communication radio
- Attitude gyro
- Radar altimeter