TM  55-1510-221-10 Table  5-1.  Operating  Limits OPERATING CONDITION GAS TORQUE MAXIMUM GENERATOR PROP OIL OIL SHP PERCENT OBSERVED RPM N₁ (10) RPM PRESS TEMP (1) TGT  ºC RPM % N₂ PSI (2) ºC TAKEOFF   (3) 850 100% 750 38,100 101.5 2000 105  to 10 to 99 135 MAX  CONT 850 100%  (4) 750 38,100 101.5 2000 105  to 10 to 99 135 MAX  CLIMB 850 100%  (4) 725 38,100 101.5 2000 105  to 0 to 99 135 MAX  CRUISE HIGH  IDLE - - - - (5) - - -40 to 99 LOW IDLE - - 660 (6) 19,500 52(min) - 60(min) -40 to 99 STARTING - - 1000(7) - - - - -4O(min) TRANSIENT - 123%  (7) 850 38,500(8)102.6(8) 2200(7) - 0 to 104 (3) MAX REVERSE(9) - 750 - 88 1900 105  to 0 to 99 135 NOTES: (1) Torque limit applies within range of 1600-2000 propeller RPM (N₂). Below 1600 RPM, torque is limited to 49%. (2) Normal takeoff and maximum continuous operation oil pressure at gas generator speeds above 72% with oil temperature between 60 and 71°C is 105 to 135 PSIG up to 21,000 feet. Above 21,000 feet, the minimum oil pressure is 85 PSIG. Plus or minus 10 PSIG fluctuations are acceptable. Oil pressure between 60 and 85 PSIG should be tolerated only for the completion of the flight at power setting not to exceed 49% torque. Oil pressure below 60 PSIG are unsafe and require that either the engine be shut down or a landing be made as soon as possible, using the minimum power required to sustain flight. During extremely cold starts, oil pressure may reach 200 PSI. (3) These values are time limited to 5 minutes. (4) Cruise torque values vary with altitude and temperature. (5)  At  approximately  70%  N₁ . (6) High TGT at ground idle may be corrected by reducing accessory load and/or increasing N₁    RPM. (7) These values are time limited to 5 seconds. (8) These values are time limited to 10 seconds. (9) This operation is time limited to 1 minute. (10) For every 5.6ºC below -48ºC ambient temperature, reduce maximum allowable N₁    by 1.6%. TABLE  5-2.  GENERATOR  LIMITS GENERATOR   LOAD 0 to 50% 50 to 80% 80 to 100%   *Right engine only MINIMUM  GAS  GENERATOR  RPM  -  N₁ WITHOUT   AIR   CONDITIONING *WITH  AIR  CONDITIONING 53% 60% 60% 65% 63% 70% 5-7