TY - JOUR
T1 - Determining the leeway drift characteristics of tropical Pacific island craft
AU - Brushett, Ben A.
AU - Allen, Arthur A.
AU - Futch, Victoria C.
AU - King, Brian A.
AU - Lemckert, Charles J.
N1 - Funding Information:
This work was financially supported by the US Coast Guard Office of Search and Rescue , US Coast Guard Academy , US Coast Guard District Fourteen, Griffith University and the Australian Research Council's Linkage Projects funding scheme LP0991159 . The authors would like to acknowledge the assistance received from the Coast Guard Academy waterfront personnel, RJ Burns; Cadets Arnold, Kennedy, and Byrd in preparation of the PWC and the personnel at Coast Guard Sector Guam. We would also like to thank the officers and crew of the USCGC SEQUOIA for their outstanding professionalism and good humour throughout the cruise. We express our sincere appreciation to the reviewers of this paper for their constructive recommendations.
PY - 2014/1
Y1 - 2014/1
N2 - An accurate understanding of the leeway drift characteristics of drifting objects is required to effectively forecast the drift of persons, vessels or objects lost at sea, and to generate efficient search areas to maximise the probability of successfully locating those missing. Presently, the most effective method for calculating the leeway drift characteristics of an object or vessel is to empirically derive the leeway coefficients of that object through field studies. The main goal of the studies is to measure how the object drifts in relation to the surface currents, due to the wind and wave action upon it. This paper outlines the determination of downwind and crosswind leeway coefficients for three small craft common to Pacific island communities for which no accurate leeway coefficients exist. These craft were: a 19 foot (5.8m) fibreglass skiff (known locally as pangas, fibres, or banana boats); a 20 foot (5.97m) fibreglass outrigger canoe; and a 2-person sit down personal water craft (PWC). Due to the vast distances between pacific islands and the remoteness of these locations it can be several days until a search can be mounted to rescue those lost at sea, hence it is paramount that an accurate description of the drift of these tropical pacific craft is available for use in search and rescue (SAR) drift models, to define appropriate search areas. This study successfully derived the leeway coefficients required for each of these three craft. The leeway speed of the outrigger canoe and PWC, both with one person on board (POB) equivalent loading, were calculated to be 2.40% and 4.24% of the wind speed respectively. The leeway speed of the skiff was found to range between 7.71% and 4.40% of the wind speed for equivalent loading between 1 POB and 13 POB.The results of these field tests have subsequently been implemented into search and rescue models by several SAR organisations worldwide. These results show that the findings herein have the potential to both increase the likelihood of finding persons adrift at sea alive, as well as reducing search costs through more effective drift prediction and efficient search area formulation.
AB - An accurate understanding of the leeway drift characteristics of drifting objects is required to effectively forecast the drift of persons, vessels or objects lost at sea, and to generate efficient search areas to maximise the probability of successfully locating those missing. Presently, the most effective method for calculating the leeway drift characteristics of an object or vessel is to empirically derive the leeway coefficients of that object through field studies. The main goal of the studies is to measure how the object drifts in relation to the surface currents, due to the wind and wave action upon it. This paper outlines the determination of downwind and crosswind leeway coefficients for three small craft common to Pacific island communities for which no accurate leeway coefficients exist. These craft were: a 19 foot (5.8m) fibreglass skiff (known locally as pangas, fibres, or banana boats); a 20 foot (5.97m) fibreglass outrigger canoe; and a 2-person sit down personal water craft (PWC). Due to the vast distances between pacific islands and the remoteness of these locations it can be several days until a search can be mounted to rescue those lost at sea, hence it is paramount that an accurate description of the drift of these tropical pacific craft is available for use in search and rescue (SAR) drift models, to define appropriate search areas. This study successfully derived the leeway coefficients required for each of these three craft. The leeway speed of the outrigger canoe and PWC, both with one person on board (POB) equivalent loading, were calculated to be 2.40% and 4.24% of the wind speed respectively. The leeway speed of the skiff was found to range between 7.71% and 4.40% of the wind speed for equivalent loading between 1 POB and 13 POB.The results of these field tests have subsequently been implemented into search and rescue models by several SAR organisations worldwide. These results show that the findings herein have the potential to both increase the likelihood of finding persons adrift at sea alive, as well as reducing search costs through more effective drift prediction and efficient search area formulation.
KW - Federated States of Micronesia (FSM)
KW - Guam
KW - Outrigger canoe
KW - Panga
KW - Personal water craft
KW - Search and rescue
KW - Tropical Western Pacific
UR - http://www.scopus.com/inward/record.url?scp=84890027262&partnerID=8YFLogxK
UR - http://www.mendeley.com/research/determining-leeway-drift-characteristics-tropical-pacific-island-craft
U2 - 10.1016/j.apor.2013.11.004
DO - 10.1016/j.apor.2013.11.004
M3 - Article
AN - SCOPUS:84890027262
SN - 0141-1187
VL - 44
SP - 92
EP - 101
JO - Applied Ocean Research
JF - Applied Ocean Research
ER -