TH-57 Limits

• Minimum: 97 percent.
• Maximum continuous: 100 percent.
• Nf overspeeds are determined on a sliding scale(Figure 4-1) depending on TOT, Nf percentage, and duration.

• Headwind: 40 KT
• Crosswind: 25 KT
• Tailwind: 17 KT

• Idle: 59 to 65%.
• normal operating range: 59 to 105 %.
• Maximum transient: 106 percent for 15 seconds.

• Ng < 79% = Min 50 psi.
• Ng 79 -94% = Min 90 psi.
• Ng > 94% = Min 115 psi.

• Max normal = 130 psi
• Max cold weather start = 150 psi

0
to 107
C.

• 1. During start
• Up to 810
  C --No Limit (No maint req)
• 810
  to 927 °C --10 second limit (Inspect turbine)
• 927
  C or above --Not allowed (Inspect turbine)

• 2. During power transient
• Up to 738 °C --No limit (No maint req)
• 738
  to 810 °C --5 minute limit (No maint req)
• 810
  to 843 °C --6 seconds limit (No maint req)
• Above 843 °C --Not allowed (Inspect turbine)

• 90-107% Nr.
• Maximum allowable Nr is 107%.
• Transient allowable Nr is 107-114% for 5 seconds.

• Cont. Op: 30-50 psi
• Minimum: 30 psi
• Maximum: 70 psi.

Temp: 15
to 110
C.

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.

• Max Continuous = 85%.
• Military power =100% for 5 minutes.
• Transient Range =100-110% for 5 seconds.

4 to 30 psi.

Note: With main generator on, the standby generator loadmeter should indicate10 percent load or less. Momentary testing of standby generator under full bus load is permitted on the ground or in the air.

Prolonged operation of the standby generator while it is the primary power supply to the essential No. 1 bus is prohibited at speeds below 65 KIAS (Vmini).

• Rotor brake should be applied between 38 and 30 percent Nr during normal operations.
• Normal Operation: 100-120 psi

• EPU: 25-30-25-30-25-30mins
• Battery: 40-60-40-60-40-30mins

Note: If a 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.

• 0 to 1,000 DA: 25, 15
• 1,000 to 2,000 DA: 20, 15
• 2,000 to 4,000 DA: 15, 15
• 4,000 to 6,000 DA: 10, 10
• 6,000 to 10,000DA: 5, 5

50 KIAS

65 KIAS

<3,000-lb — 130 KIAS. Decrease Vne 3.5 KIAS per 1,000' above 3,000-DA.

>3,000-lb — 122 KIAS. Decrease Vne 7.0 KIAS per 1,000' above 3,000-DA

<3,000-lb — 122 KIAS. Decrease Vnei 3.5 KIAS per 1,000' above 3,000-DA.

>3,000-lb — 122 KIAS. Decrease Vnei 7.0 KIAS per 1,000' above 3,000-DA

110 KIAS

100 KIAS

80 KIAS

• AFCS OFF:
• <3,000-lb — 20,000-PA; 18,000-DA
• >3,000-lb — 16,000-PA; 13,000-DA.

• IFR or AFCS ON:
• <3,000-lb — 11,500-PA; 13,500-DA.
• >3,000-lb — 8,500-PA; 11,000-DA.

1,000 feet per minute (IMC)

0.5g-2.5g at max gross wt

• 3200 lb
• 3350 lb with external load

• 1. The minimum flightcrew consists of one pilot and a qualified observer.
• 2. The minimum flightcrew for IFR operations is two pilots, with at least one being an instrument-rated pilot.
• 3. The minimum crew weight is 180 pounds.

• 1. Cyclic force trim system.
• 2. MINISTAB FCS (pitch and roll).
• 3. Main generator.
• 4. Standby generator.
• 5. Battery protection circuit.
• 6. Instantaneous VSI.
• 7. Two attitude indicators (one automatically powered by approved standby battery source in the event of powerloss).
• 8. One operable communication system.
• 9. One operable navigation system appropriate to the routes to be flown.
• 10. Radar altimeter.
• 11. Other equipment as required by the operating rules.

The TH-57B/C helicopter is approved for VFR operations in day and night nonicing conditions.

The TH-57C helicopter is approved for IFR operations in day and night nonicing conditions. IFR operations are not permitted with any doors removed or with external loads.

• 1. No aerobatic maneuvers are permitted.
• 2. Angles of bank exceeding 60 degrees are prohibited.
• WARNING: Engine failures at high angles of bank may cause aircraft roll reversal characteristics.
• 3. Protracted operations in the AVOIDand CAUTION areas of the height velocity diagram (Figure 4-6) shall not be made.
• 4. No intentional entry into blade stall or vortex ring state (power settling) is permitted.
• 5. Hovering turns exceeding a rate of 45_ per second are prohibited.

• 1. All instrument and circuit breaker panel lights.
• 2. All exterior lights.
• 3. Operable communication radio.
• 4. Attitude gyro.
• 5. Radar altimeter.

• 1. Radar altimeter.
• 2. Vertical Speed Indicator.
• 3. Crewmember’s survival equipment shall include all required personal survival equipment per OPNAVINST3710 series including inflatable life preservers,HABD(helicopter aircrewbreathing device), an anti--exposureensemble (as required), survival radio, signaling device and hoisting harness. {HARSH presevers}
• Note: Due to weight and space restrictions associated with the TH--57, life rafts are not required.