Limitations
CSP–520N–1
MD 520N (500N) ROTORCRAFT FLIGHT MANUAL
R
Revision 2
2–5
FAA Approved
2–7. POWERPLANT LIMITATIONS ALLISON 250–C20R/2
Engine torque limits:
Maximum takeoff power (5 minute): 101.8 psi torque
Maximum continuous: 89.8 psi torque
Transient torque limits:
101.8 to 112.2 psi torque (red dot ton torque indicator) for 10 seconds at
100 percent N
2
.
Turbine Outlet Temperature limits:
Maximum takeoff (5 minute): 810
°
C
Maximum continuous: 752
°
C
Maximum for starting (lightoff): 150
°
C
Transient limits:
During start and shutdown: 810
°
C and above for 10 seconds or less with
a momentary peak temperature of 927
°
C for not more than 1 second.
During power changes in flight:
810
°
C to 843
°
C for 6 seconds for aircraft with ‘‘analog only" TOT indica*
tor.
810
°
C to 899
°
C for 6 seconds for aircraft with ‘‘analog/digital" TOT indi*
cator.
Gas Producer (N
1
) speed limits:
Maximum continuous: 105%.
Minimum: ground idle speed 64%.
Transient limits:
106% for 15 seconds.
