4. For simulated hull pitching (maximum pitch angle of 1.85 
degrees): 
a. The maximum values of measured total forces and bending 
moments increased over the corresponding values without hull pitch 
by 5 percent for quasi-steady simulation and by 23 percent for un- 
steady simulation with model pitching frequency equal to 0.8 hertz 
(full scale equivalent frequency is 0.16 hertz). 
b. The peak-to-peak circumferential variation of the measured 
total forces and bending moments increased over the corresponding 
values without hull pitch by approximately 5 percent for quasi- 
steady simulation and by approximately 50 percent for unsteady 
simulation with model pitching frequency equal to 0.8 hertz. MThere- 
fore, any quasi-steady simulation of ship motions is completely in- 
adequate for estimating the effect of ship motions on unsteady pro- 
peller blade loading. 
5. For the simulated acceleration maneuver: 
a. The dominant first harmonic of the measured hydrodynamic 
forces and bending moments varied in a nearly linear manner with 
the product of ship speed and propeller rotational speed. 
b. The acceleration of the hull did not have a significant ef- 
fect on the measured loads. Therefore, propeller blade loading 
during an acceleration maneuver can be adequately estimated by 
quasi-steady experiments. 
c. The maximum time-average values of measured forces and bend- 
ing moments per revolution were in the range of 1.21 to 1.29 of the 
time-average values during full-power steady-ahead operation for 
hydrodynamic loads, and in the range 1.16 to 1.21 of the time-average 
values during full-power steady-ahead operation for total loads. 
d. The simulated acceleration condition did not expose the pro- 
peller to higher peak loads than those to which it is exposed during 
full power steady-ahead operation. However, these loads are very 
sensitive to the maneuver simulated and substantially higher peak 
loads could be developed during other acceleration maneuvers. 
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