Manoeuvrability in waves is discussed from the point of view of the dangers of broaching-to when a ship is running before the sea. Conditions are assessed under which this may occur, illustrated by documented cases, including the Wahine disaster in 1968. Because of the problems involved in investigating broaching-to by means of free-running model tests, there is an urgent need for reliable mathematical models: however, theories published so far, based on two different simplifications, are shown to have limitations. It is argued that the theory must take account of pitching, surging, rolling and orbital motion of the water particles.
Get full access to this article
View all access options for this article.
References
1.
HogbenN.LumbF. E.Ocean wave statistics1967 (H. M. S. O., London).
2.
T. E. V. ‘Wahine’. Shipping Casualty, 10 April 1968. Report of court and annex thereto, 1968 (Wellington, New Zealand).
3.
SaundersH. E.Hydrodynamics in ship design1965, Vol. III (Soc. Nav. Archit. Mar. Engrs).
4.
Admiralty manual of seamanship 19641964, Vol. III (H. M. S. O., London).
5.
Admiralty manual of navigation1960, Vol. II (H. M. S. O., London).
6.
BurcherR. K. ‘Developments in ship manoeuvrability’, Jl R. Instn nav. Archit.1972114, 1.
7.
Du CaneP.GoodrichG. J.The following sea, broaching and surging, Trans. R. Instn nav. Archit.1962104.
8.
StuntzG. R.TaylorR. J. ‘Some aspects of bow thruster design’, Trans. Soc. nav. Archit. mar. Engrs196472.
9.
DavidsonK. S. M.SchiffR. I.Turning and course-keeping qualities, Trans. Soc. nav. Archit. mar. Engrs1946.
10.
DavidsonK. S. M.Dynamics of turning and course keeping of ships, Sixth Int. Congr. Applied Mechanics1946.
11.
WeinblumG. P.On the directional stability of ships in calm water and in a regular seaway, First Am. Congr. Applied Mechanics1951.
12.
GrimO. ‘Das Schiff in von Achtern Auflanfender See’, Jb. schiffbautech. Ges.195145.
13.
RydillL. J. ‘A linear theory of the steered motion of ships in waves’, Trans. Instn nav. Archit.1959101.
14.
WahabR.SwaanW. A. ‘Course keeping and broaching of ships in following seas’, J. Ship Res. 1964 (April).
15.
EdaH.CraneC. L. ‘Steering characteristics of ships in calm water and waves’, Trans. Soc. nav. Archit. mar. Engrs1965.
16.
TasaiF. ‘On the swaying, yawing and rolling motions of ships in oblique waves’, Trans. J. N. S. A. 1966.
17.
VugtsJ. H. ‘The coupled roll-sway-yaw performance in oblique waves’, Proc. Twelfth I. T. T. C., Rome, 1969.
18.
EnglishJ. W. ‘The design and performance of lateral thrust units for ships’, Trans. R. Instn nav. Archit.1963105.
