UNCLASSIFIED 
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a READ INSTRUCTIONS al 
| REPORT DOCUMENTATION PAGE | BEFORE COMPLETING FORM —_| 
. REPORT NUMBER 2. GOVT ACCESSION NO,| 3. RECIPIENT'S CATALOG NUMBER | 
4. TITLE (and Subtitle) 5. TYPE OF REPORT & PERIOD COVERED 
A NONLINEAR MATHEMATICAL MODEL 
OF MOTIONS OF A PLANING BOAT 
8. CONTRACT OR GRANT NUMBER(e) 
IN REGULAR WAVES 
» AUTHOR(a) 
Ernest E. Zarnick 
10. PROGRAM ELEMENT, PROJECT, TASK 
AREA & WORK UNIT NUMBERS 
ZF 43 421001 
Work Unit 1-1500-100 
12, REPORT DATE 
March 1978 
13. NUMBER OF PAGES 
86 
1S. SECURITY CLASS. (of thie report) 
UNCLASSIFIED 
1Sa. DECL ASSIFICATION/ DOWNGRADING | 
SCHEDULE 
APPROVED FOR PUBLIC RELEASE: DISTRIBUTION UNLIMITED 
” PERFORMING ORGANIZATION NAME AND ADDRESS 
David W. Taylor Naval Ship Research 
and Development Center 
Bethesda, Maryland 20084 
- CONTROLLING OFFICE NAME AND ADDRESS 
Naval Sea Systems Command (SEA 035) 
Washington, D.C. 20362 
- MONITORING AGENCY NAME & AODORESS(If different from Controlling Office) 
» DISTRIBUTION STATEMENT (of this Report) 
. DISTRIBUTION STATEMENT (of the abatract entered in Block 20, if different from Report) 
- SUPPLEMENTARY NOTES 
- KEY WORDS (Continue on reverse aide if neceseary and identify by block number) 
Planing Boat Motions 
Hydrodynamic Impact 
Small Boat Worthiness 
Nonlinear Ship Motions in Waves 
. ABSTRACT (Continue on reverse aide if neceseary and identify by block number) 
A nonlinear mathematical model has been formulated of a craft having a constant deadrise angle, planing 
in regular waves, using a modified low-aspect-ratio or strip theory. It was assumed that the wavelengths 
would be large in comparison to the craft length and that the wave slopes would be small. The coefficients 
in the equations of motion were determined by a combination of theoretical and empirical relationships. 
A simplified version for the case of a craft or model being towed at constant speed was programed for 
computations on a digital computer, and the results were compared with existing experimental data. 
(Continued on reverse side) 
DD en, 1473 EDITION OF 1 Nov 65 1s OBSOLETE 
1 JAN 73 Pritciaate oilele sor UNCLASSIFIED 
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