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Appendix II to Part 1045—Duty Cycles for Propulsion Marine Engines

Duty Cycles for Propulsion Marine Engines

CorpusDaily eCFR
Displayed edition2026-04-27
Last updated2026-04-27

Appendix II to Part 1045—Duty Cycles for Propulsion Marine Engines

(a) The following duty cycle applies for discrete-mode testing:

E4 Mode No.Engine

speed 1
Torque

(percent) 2
Weighting

factors
1Maximum test speed1000.06
280%71.60.14
360%46.50.15
440%25.30.25
5Warm idle00.40
1 Speed terms are defined in 40 CFR part 1065. Percent speed values are relative to maximum test speed.
2 Except as noted in § 1045.505, the percent torque is relative to maximum torque at maximum test speed.

(b) The following duty cycle applies for ramped-modal testing:

RMC ModeTime in mode

(seconds)
Engine speed 1 2Torque (percent) 2 3
1a Steady-state225Idle0
1b Transition20Linear transitionLinear transition
2a Steady-state63Maximum test speed100
2b Transition20Linear transitionLinear transition
*3a Steady-state27140%25.3%
3b Transition20Linear transitionLinear transition
4a Steady-state15180%71.6%
4b Transition20Linear transitionLinear transition
5a Steady-state16160%46.5%
5b Transition20Linear transitionLinear transition
6 Steady-state229Warm idle0
1 Speed terms are defined in 40 CFR part 1065. Percent speed values are relative to maximum test speed.
2 Advance from one mode to the next within a 20-second transition phase. During the transition phase, command linear progressions of speed and torque from the speed setting and torque setting of the current mode to the speed setting and torque setting of the next mode.
3 Except as noted in § 1045.505, the percent torque is relative to maximum torque at maximum test speed.