TH-57 Limits Flashcards
What are the Nf power Minimums and Maximums?
How are overspeeds determined?
Minimum Nf is 97%
Max continuous Nf is 100%
Overspeeds are determined on a sliding scale
What is the Nf avoid range?
A 71% to 88% Nf steady state speed avoidance range is required for all operations.
What is considered “steady state” when talking about the Nf avoid range?
Remaining at an Nf speed for more than one second.
When are you allowed to operate in the Nf avoid range?
-During transient operations
-During pretakeoff checks when rotating the twist grip to 70% Ng (Nf should not purposely stabilize in this range)
-During an autorotation when Nf splits away from Nr.
What is the idle engine Ng?
62 +/-2%
What is the normal Ng operating range, and what is the maximum transient Ng allowed?
60% to 105% Normal operating range
106% for 15 seconds Maximum transient
What are the Minimum Engine oil Px limits?
Ng < 79% Min 50psi
79% 94% Min 90 psi
Ng > 94% Min 115 psi
What is the Maximum oil pressure and what is the exception?
Max 130 Psi
Allowed up to 150 psi immediately after a cold start
What is the engine oil temperature range?
0 to 107 deg C
What are your rotor engage, disengage limits?
40 Kts Max from the front
25 kts Max from either side
17 Kts Max from the rear
What is the Start ToT Limits?
up to 810 deg C No limit
810-927 deg C 10 seconds
927 deg C Max
What are your powered on ToT Limits?
up to 738 deg C No limit
738-810 deg C 5 minutes
810-843 deg C 6 seconds
843 deg C Max
What is the minimum fuel reserve for the TH-57?
10 Gallons
What is the Nr power on and power off Limits?
Power on: Min 97% Max 100%
Power off: normal operating range is 90-107%
What is the Nr avoid range?
Continuous operation in the 50-60% range could cause isolation mount damage.
What are the continuous Transmission oil pressure limits? What is the Min and Max?
Continuous operation between 30 psi and 50 psi.
Minimum pressure is 30 psi, Maximum pressure is 70 psi.
What’s required if Transmission oil pressure is between 50 and 70 psi? What could happen when operating in this range?
It SHALL be documented on a MAF after flight. There is no detrimental affect to the transmission when operating between 50 and 70 psi.
What are the Transmission oil Temperature limits?
15 to 110 deg C
What are your the torque limits?
85% Max continuous
85-100% Military power for 5 minutes
100-110% for 5 seconds
What is your fuel boost pump pressure range?
4 to 30 psi
What should the standby generator indicate when the main generator is on?
With the main generator on, the standby should indicate 10% load or less
What is the limit of operating with your standby generator as the main power supply?
Porlonged operation of the standby generator when it is the primary power supply to the essential No. 1 bus is prohibited at speeds below 65 KIAS.
What are your rotor break limits? What happens if you engage it below this limit?
Rotor brake should be applied between 38 and 30% Nr during normal operations. Application below 30% Nr may cause damage to the drivetrain
What are your starter limits on external power?
25 seconds - ON
30 seconds - OFF
25 seconds - ON
30 seconds - OFF
25 seconds - ON
30 minutes - OFF
What are your starter limits on battery power?
40 seconds - ON
60 seconds - OFF
40 seconds - ON
60 seconds - OFF
40 seconds - ON
30 minutes - OFF
What are your starter limits if light off occurs?
If light-off occurs within the first 20 seconds on the start sequence, the starter may be operated for 60 seconds with a 60 second cooling period. Three such attempts may be made in a 30 minute period, then wait 30 minutes for the starter to cool.
What is your Vne with AFCS off and AFCS on?
OFF - 130 KIAS
ON - 122 KIAS
What is your max sideward and rearward flight?
DA / Max Sideward / Max Rearward
0-1000 / 25 / 15
1000-2000 / 20 / 15
2000-4000 / 15 / 15
4000-6000 / 10 / 10
6000-10K / 5 / 5
What is your max rate of climb airspeed?
50 KIAS
What is your max IFR Speed?
65 KIAS
What is your max speed with any doors off?
110 KIAS
What is your max autorotational speed?
100 KIAS
What is your turbulence penetration speed?
80 KIAS
What is your max operating altitude with FCS off?
3000 lbs GW and below: 20K PA / 18K DA
Above 3000 lbs GW: 16K PA / 13K DA
What is your max operating altitude with FCS on or IFR?
3000 lbs GW and below: 11.5K PA / 13.5k DA
Above 3000 lbs GW: 8.5k PA / 11k DA
What are your climb and descent limits in IMC?
Should not exceed 1000 ft/min
What are your acceleration (G forces) limits?
Between 2.5 and 0.5 Positive Gs
What are your Gross Weight limits?
Internally: 3200 lbs
including external cargo : 3350 lbs
What are your Longitudinal CG limits with FCS off or on?
FCS OFF: 106.0-114.2
FCS ON: 106.75-112.5
What are your CG limits with doors removed?
106.0-110.0
What is your minimum flight crew?
One pilot and one qualified observer
What is the minimum flight crew for IFR ops?
Two pilots, with at least one being an instrument rated pilot
What is the minimum flight crew for CAL and LOG ops?
One pilot, one qualified observer, and an aircrewman. No aircrewman required, if both pilots are qualified in model.
What is the minimum crew weight?
180 lbs
What are the prohibited operations?
- The TH-57B is prohibited from operating in IMC or icing conditions.
- The TH-57C is prohibited from operating in icing conditions
- IFR ops are prohibited with any doors removed or with an external load
- Asymmetrical doors off flight is prohibited.
What are the prohibited in flight maneuvers?
- Aerobatic maneuvers
- Protracted operations in the AVOID and CAUTION areas of the height/velocity diagram
- Fully developed vortex right state
- Intentional entry into blade stall
- Hovering turns exceeding a rate of 45 deg per second
