TM 55-1510-222-10 maintain   an   adequate   supply   of   systems   pneumatic bleed air. 5-12. PITOT HEAT LIMITATIONS. a. Pitot heat should not be used for more than 15 minutes while the aircraft is on the ground. Section III.  POWER LIMITS 5-13. ENGINE LIMITATIONS. Observe limitations found in Table 5-1 during operation of  this  aircraft,  equipped  with  two  Pratt  and  Whitney  of Canada,  Ltd.    PT6A-67  engines.    Each  column  is  a separate    limitation.        The    limits    presented    do    not necessarily occur simultaneously.  Whenever operating limits  are  exceeded,  the  pilot  should  record  the  value and duration of' the condition encountered, in the aircraft log.        Operation    of    the    engines    is    monitored    by instruments,    with    reference    to    the    operating    limits marked on the face of each instrument. Table 5-1.  Engine Operating Limitations TORQUE MAXIMUM GAS PROP OIL OIL OPERATING % OBSERVED GENERATOR RPM PRESS TEMP CONDITION TGT°C RPM N, N2 PSI (2) (3) STARTING (1) 1000(4) - - 200 -40 (min) (max) LOW IDLE - 750(5) 62 (min) 1000 (min) 60 (min) -40 to 110 HIGH IDLE - - (6) 1000 (min) - TAKEOFF (5 MIN.) 100 840 104 1700 90 to 135 10 to 110 MAX. CONT. 100 830 104 1700 90 to 135 10 to 105 MAX. CRUISE and (7) (9) 810 104 (9) 90 to 135 10 to 105 MAX CLIMB NORMAL CRUISE and (7) (9) 800 104 (9) 90 to 135 10 to 105 NORMAL CLIMB MAX REVERSE 81 760 88% 1650 90 to 135 10 to 105 TRANSIENT 150(8) 870(8) 104 1870(8) 40 (min) -40 to 110 200 (max) (8) BT00191 NOTES: The  limits  presented  do  not  necessarily  occur  simultaneously.    Whenever  operation  limits  are  exceeded  the  pilot  will record the value and duration of the condition encountered on DA Form 2408-13. (1)   Torque limit applies within range of 1000 to 1700 propeller RPM (N2).  Below 11000 RPM, torque is limited to 59%. (2)   An engine oil temperature of 74 C to 80 C is recommended. (3)   Oil temperature limits are -40 C to 105 C.  However, temperatures of up to 110 C are permitted for a maximum time of 10 minutes. (4)   These values are time limited to 5 seconds. (5)   High TGT at ground idle may be corrected by reducing accessory load and/or increasing N₁RPM. (6)   At approximately 72% N_1. (7)   Cruise torque values to be set per Chapter 7. (8)   These values are time limited to 20 seconds. (9)   Torque limited to 100% when operating at 1500 RPM (N2).  Torque limited to 91% when operating at 1700 RPM (N₂). 5-6