Seakeeping
Seakeeping performance was one
of the most important design parameters for AGOR 26 since the main point of the
program is to expand the oceanographic fleet’s ability to perform research in
higher sea states. The design goal
for seakeeping was full operability in upper sea state 6 (SS6) in all headings.
Full operability was defined as meeting the following motion limits:
Pitch:
3 degrees
Roll:
5 degrees
Heave Acceleration:
0.4 Gs
Lateral Acceleration:
0.2 Gs
The seakeeping analysis was computer generated based on model test damping factors for similar hull forms and the MIT WAMIT computer code. At the conclusion of Phase I, the ship meets all motion criteria with the exception of the 3 degree pitch requirement at zero speed. The pitch requirement is met in lower SS6 but not in upper SS6, particularly in following seas. The computer calculated values were 3.41 degrees of pitch at best heading and 4.9 degrees of pitch at worst heading in upper SS6. Further review will be performed in Phase II to determine if more improvement can be achieved. Computer generated seakeeping predictions are shown in the following figures:
Pitch Response Roll Response
Heave Acceleration - G's Heave Response
Sway Acceleration at CG