Contents of the "Proceedings of the Twenty-First American Towing Tank Conference, 1987"

Proceedings of the

Twenty-First

American

Towing Tank

Conference

edited by

Richard F . Messalle

Sponsored jointly by:

Naval Studies Board of the U.S. National Research Council

AMOCO Productions

Bird-Johnson & Company

Boeing Company

Chevron

Gibbs & Cox

M. Rosenblatt & Sons

National Steel & Shipbuilding Co.

Newport News Shipbuilding & Drydock Company

ORI, Inc.

Society of Naval Architects & Marine Engineers

T R A C O R

Tracor Hydronautics, Inc.

Peterson Building, Inc.

NOTICE: The p r o j e c t t h a t i s the s u b j e c t o f t h i s r e p o r t was approved by the Governing Board of the N a t i o n a l Research Council, whose members are drawn from the Councils o f the National Academy o f Sciences, the N a t i o n a l Academy o f Engineering, and the I n s t i t u t e o f Medicine. The members o f the committee respon-s i b l e f o r the r e p o r t were chorespon-sen f o r t h e i r respon-s p e c i a l competencerespon-s and w i t h regard f o r appropriate balance.

This r e p o r t has been reviewed by a group other than the authors according t o procedures approved by a Report Review Committee c o n s i s t i n g o f members o f the National Academy o f Sciences, the N a t i o n a l Academy o f Engineering, and the I n s t i t u t e o f Medicine.

The National Research Council was e s t a b l i s h e d by the National Academy o f Sciences i n 1916 t o associate the broad community o f science and technology w i t h the Academy's purposes o f f u r t h e r i n g knowledge and o f a d v i s i n g the f e d e r a l government. The Council operates i n accordance w i t h general p o l i c i e s determined by the Academy under the a u t h o r i t y o f i t s congressional c h a r t e r o f 1863, which e s t a b l i s h e s the Academy as a p r i v a t e , n o n p r o f i t , s e l f - g o v e r n i n g membership cor-p o r a t i o n . The Council has become the cor-p r i n c i cor-p a l ocor-perating agency o f both the N a t i o n a l Academy o f Sciences and the N a t i o n a l Academy o f Engineering i n the con-duct o f t h e i r services t o the government, the p u b l i c , and the s c i e n t i f i c and engineering communities. I t i s administered J o i n t l y by both academies and the I n s t i t u t e o f Medicine. The National Academy o f Engineering and the I n s t i t u t e o f Medicine were e s t a b l i s h e d i n 1954 and 1970, r e s p e c t i v e l y , under the character o f the N a t i o n a l Academy o f Sciences.

This work r e l a t e d t o Department of Navy Contract N0001l)-85-G-0I30 issued by the O f f i c e o f Naval Research under c o n t r a c t a u t h o r i t y NR 201-121. However, the content does not n e c e s s a r i l y r e f l e c t the p o s i t i o n or the p o l i c y o f the Department of the Navy or the government, and no o f f i c i a l endorsement should be i n f e r r e d .

The United States Government has a t l e a s t a r o y a l t y - f r e e , nonexclusive and i r r e v o c a b l e l i c e n s e throughout the world f o r government purposes t o p u b l i s h , t r a n s l a t e , reproduce, d e l i v e r , perform, and dispose o f a l l or any o f t h i s work, and t o a u t h o r i z e others t o do so.

Copies a v a i l a b l e from:

The 21st American Towing Tank Conference Mr. Frank H. S e l l e r s (Treasurer)

MPR Associates, I n c . 1050 Connecticut Ave. N.W. Washington, D.C. 20036 Phone: 202-659-2320

SPONSORS

The E x e c u t i v e Committee o f the 21st American Towing Tank Conference extend i t s thanks t o those o r g a n i z a t i o n s whose f i n a n c i a l c o n t r i b u t i o n s made t h i s Conference p o s s i b l e . Because o f t h e i r generous c o n t r i b u t i o n s c o p i e s o f the Pro ceedings w i l l be d i s t r i b u t e d t o a l l member o r g a n i z a t i o n s o f the I n t e r n a t i o n a l Towing Tank Conference.

Naval S t u d i e s Board o f the U.S. N a t i o n a l Research C o u n c i l

N a t i o n a l S t e e l & S h i p b u i l d i n g Co.

Newport News S h i p b u i l d i n g & Drydock Company

AMOCO P r o d u c t i o n s

Bird-Johnson & Company

ORI, I n c . Boeing Company S o c i e t y o f Naval A r c h i t e c t s & Marine Engineers Chevron TRACOR

Gibbs & Cox J

Tracer H y d r o n a u t i c s , I n o .

M. R o s e n b l a t t & Sons

PREFACE

The t w e n t y - f i r s t meeting o f the American Towing Tank Conference (ATTC) was h e l d a t the N a t i o n a l Academy o f Sciences, Washington, D.C. from the 5 t h t o the 7 t h o f August 1 9 8 6 . The Conference was hosted by the David T a y l o r Naval Ship Research and Development Center and was a t t e n d e d by l 8 l ) d e l e g a t e s from N o r t h and South America r e p r e s e n t i n g IB businesses, 18

government e s t a b l i s h m e n t s and 13 u n i v e r s i t i e s . E i g h t t e c h n i c a l committee r e p o r t s and 50

t e c h n i c a l papers (by 103 a u t h o r s ) were p r e -sented a t the Conference. The p r e s e n t a t i o n o f the papers was l i m i t e d t o a t o t a l o f 15.5 hours i n the t h r e e days. T h i s r e s t r i c t e d the d i s c u s s i o n s from the f l o o r . The papers were not a v a i l a b l e f o r d i s t r i b u t i o n t o p a r t i c i p a n t s b e f o r e the Conference f o r f o r m a l r e v i e w . Because o f t h i s , i t was requested t h a t a l l q u e s t i o n e r s from the f l o o r submit f o r m a l ques-t i o n s a f ques-t e r w a r d s f o r i n c l u s i o n i n ques-the

Proceedings. Only a few d i d so. The Conference p a r t i c i p a n t s b e n e f i t e d from t h e p o i n t e d q u e s t i o n s and exchange o f e x p e r i e n c e s but the reader o f the proceedings w i l l n o t . The Conference was a success because i t l e t us renew o l d a c q u a i n t a n c e s , exchange i n f o r m a t i o n , and share e x p e r i e n c e s .

The ATTC i s a v o l u n t a r y a s s o c i a t i o n o f e s t a b l i s h m e n t s and u n i v e r s i t i e s i n the Western Hemisphere t h a t have r e s p o n s i b i l i t y i n the p r e -d i c t i o n o f hy-dromechanic performance o f s h i p s and waterborne c r a f t based on experiments on s m a l l models or from t h e o r e t i c a l c a l c u l a t i o n s . The ATTC i s p u r e l y a communicative body w i t h no a u t h o r i t y and membership i s v o l u n t a r y and s e l f - s u p p o r t i n g . Meetings are h e l d every t h r e e years i n the Western Hemisphere, i n the year p r i o r t o the I n t e r n a t i o n a l Towing Tank Conference (ITTC). At the Conference, the r e p r e s e n t a t i v e t o the E x e c u t i v e Committee o f the ITTC i s e l e c t e d t o r e p r e s e n t the Western Hemisphere. The product o f the Conference are Proceedings which are p u b l i s h e d and p r o v i d e d t o a l l r e g i s t e r e d a t t e n d e e s and made a v a i l a b l e to o t h e r s . The cost o f p r o d u c i n g and d i s t r i b -u t i n g the Proceedings comes from r e g i s t r a t i o n fees and f i n a n c i a l c o n t r i b u t i o n s made by i n t e r e s t e d o r g a n i z a t i o n s . Because o f the gen-erous s u p p o r t o f our sponsors, c o p i e s o f the Proceedings w i l l be d i s t r i b u t e d t o a l l member o r g a n i z a t i o n s o f the ITTC.

The E x e c u t i v e Committee o f the 2 1 s t ATTC s e l e c t e d the nine t e c h n i c a l areas o f

c a v i t a t i o n , h i g h speed v e h i c l e s and s a i l i n g , ice t e s t i n g , new f a c i l i t i e s and t e c h n i q u e s , ocean e n g i n e e r i n g , p r o p u l s i o n , r e s i s t a n c e and f l o w , seakeeping, and s t e e r i n g and maneuvering f o r review by the Conference. The E x e c u t i v e Committee then formed committees f o r r e v i e w i n g each o f these areas and s e l e c t e d chairmen. T e c h n i c a l sessions were h e l d on each o f the

t e c h n i c a l areas. The chairman o f each o f these t e c h n i c a l committees was r e s p o n s i b l e f o r choosing the papers t o be p r e s e n t e d , c o o r d i -n a t i -n g t h e w r i t t e -n papers, p r e s e -n t a t i o -n o f the s t a t e - o f - t h e - a r t r e p o r t and c h a i r i n g the s e s s i o n . The h i g h success o f t h e Conference was l a r g e l y due t o the work o f these chairmen and t h e i r e f f o r t s are g r a t e f u l l y acknowledged. The work o f the a u t h o r s i n s h a r i n g t h e i r research i s a l s o g r a t e f u l l y acknowledged, e s p e c i a l l y s i n c e w r i t i n g conference papers i s a task done a f t e r normal work hours and i s u s u a l l y not supported by t h e sponsor.

The E x e c u t i v e Committee o f the 2 1 s t ATTC extends i t s thanks and g r a t i t u d e t o those o r g a n i z a t i o n s whose f i n a n c i a l c o n t r i b u t i o n s helped make t h i s Conference p o s s i b l e . They are i d e n t i f i e d on the f o l l o w i n g page o f these Proceedings. We are much i n d e b t e d t o Vice Admiral J.H. Webber, C h i e f Engineer o f the Navy, f o r g i v i n g the keynote address. His address i s i n c l u d e d i n t h e Proceedings.

As w i t h any Conference, t h e r e are those i n d i v i d u a l s who worked behind the scenes w i t h -out whom the Conference would not have been s u c c e s s f u l . The E x e c u t i v e Committee would l i k e t o g i v e s p e c i a l thanks t o Lee Hunt, E l i z a b e t h Lucks, and Mary Gordon o f the Naval S t u d i e s Board f o r the arrangements made ab the N a t i o n a l Academy o f Sciences and t o the h e l p they gave b e f o r e and d u r i n g the Conference. We a l s o thank Kay Adams, A i i e e n Tse, Z e r l i n a Chen, and Sharon Sporr f o r h a n d l i n g t h e correspondence, c o l l a t i n g papers, a r r a n g i n g the s o c i a l a c t i v i t i e s , r e g i s t r a t i o n , e t c . There are many o t h e r s on the s t a f f o f the David T a y l o r Naval Ship Research and

Development Center whose time and s u g g e s t i o n s were i n v a l u a b l e and a l s o deserve s p e c i a l

thanks.

W i l l i a m B. Morgan, Chairman Richard F. M e s s a l l e , S e c r e t a r y

MEMBERS OF THE EXECUTIVE COMMITTEE 21ST AMERICAN TOWING TANK CONFERENCE

Dr. W i l l i a m Morgan (Chairman) David T a y l o r Naval Ship Research

and Development Center Code 1500

Bethesda, MD 2008iJ-5000

( 2 0 2 - 2 2 7 - 1 5 7 8 )

Mr. Richard F. Messalle ( S e c r e t a r y ) David T a y l o r Naval Ship Research

and Development Center Code 1506 Bethesda, MD 20081)-5000 (202-227- 1 3 1 7 ) Mr. Frank DeBord, J r . O f f s h o r e Technology C o r p o r a t i o n 578 E n t e r p r i s e S t r e e t Escondido, CA 92025 (619-746-5511) Mr. David C. Murdey I n s t i t u t e f o r Marine Dynamics Box 12093 St. John's, Newfoundland A1B-3T5 CANADA ( 7 0 9- 7 7 2 - 2 3 2 6 ) Dr. D a n i e l S a v i t s k y Davidson L a b o r a t o r y Stevens I n s t i t u t e o f Technology C a s t l e P o i n t S t a t i o n Hoboken, NJ 07030 (201-120- 5 3 0 1 ) Mr. Frank H. S e l l e r s ( T r e a s u r e r ) MPR A s s o c i a t e s , I n c . 1050 C o n n e c t i c u t Avenue, NW Washington, DC 20036 ( 2 0 2 - 6 5 9 - 2 3 2 0 ) P r o f . Armin W. Troesch Ship Hydrodynamics L a b o r a t o r y U n i v e r s i t y o f Michigan N o r t h Campus Ann A r b o r , MI 18109 (313-763- 6 6 1 1 ) P r o f . Bruce Johnson Naval Systems E n g i n e e r i n g Dept.

U.S. Naval Academy A n n a p o l i s , MD 2 1 1 0 1

( 3 0 1 - 2 6 7 - 3 8 7 1 )

TECHNICAL COMMITTEE CHAIRMEN P r o p u l s i o n Committee P r o f . W i l l i a m S. Vorus 211 NA&ME B l d g . N o r t h Campus The U n i v e r s i t y o f Michigan 2600 Draper Ann Arbor, MI 18109-2115 Phone: 313-761-8311 Ocean E n g i n e e r i n g Committee Mr. Frank W. DeBord, J r . O f f s h o r e Technology C o r p o r a t i o n 578 E n t e r p r i s e S t r e e t Escondida, CA 92025 Phone: 619-716-5111 Resistance and Flovj Committee

Dr. Edwin P. Rood

David T a y l o r Naval Ship R&d Center Code 1513

Bethesda, MD 2 0 0 8 4 - 5 0 0 0

Phone: 2 0 2 - 2 2 7 - 1 5 2 9

New F a c i l i t i e s and Techniques Committee Mr. David C. Murdey I n s t i t u t e f o r Marine Dynamics N a t i o n a l Research C o u n c i l Box 12093 St. John's, Newfoundland AlB 3T5 CANADA Phone: 709-772-2326

s t e e r i n g and Maneuvering Committee Mr. Thomas Waters

David T a y l o r Naval Ship R&D Center Code 1562 Bethesda, MD 20081-5000 Phone: 202-227-1216 I c e T e s t i n g Committee Dr. Steven Jones I n s t i t u t e f o r Marine Dynamics N a t i o n a l Research C o u n c i l Box 12093 St. John's, Nev/foundland AlB 3T5 CANADA Phone: 709-772-2326 Seakeeping Committee Mr. J e f f r e y T. D i l l i n g h a m 133 NA&ME B l d g . , N o r t h Campus The U n i v e r s i t y o f Michigan 2600 Draper Ann Arbor, MI 18109-2115 Phone: 313-763-5006 C a v i t a t i o n Committee Dr. Michael L. B i l l e t A p p l i e d Research L a b o r a t o r y The P e n n s y l v a n i a S t a t e Univ. Box 30 S t a t e C o l l e g e , PA 16801 Phone: 811-865-1711 High Speed V e h i c l e s and S a i l i n g Committee Mr. Peter V/. Brown Stevens I n s t i t u t e o f Technology Davidson L a b o r a t o r y 711 Hudson S t r e e t Hoboken, NJ 07030 Phone: 201-120-5289

CONTENTS

KEYNOTE ADDRESS

THE MARITIME TECHNOLOGY REVOLUTION 1946-1986, Vice A d m i r a l J.H. Webber,

C h i e f Engineer o f the Navy 1 SESSION I : PROPULSION

Chairman: W. S. Vorus, The U n i v e r s i t y o f M i c h i g a n , Ann A r b o r , Michigan

REPORT OF THE PROPULSION COMMITTEE 9 MARINE PROPULSORS FOR MINIMUM SHAFT-HORSEPOWER, T.E. B r o c k e t t and R.A.

Korpus 19 EVALUATION OF SOME PROPELLER ANALYSIS METHODS, J.L. Kennedy, D.J. Noble,

and CM. Casgrain 29 THE WATER TUNNEL AS A TOOL IN SURFACE SHIP PROPULSION DESIGN, R.A.

Johnson, W.S. G e a r h a r t , and A.L. T r e a s t e r 37 APPLICATION OF A CONSTANT ACCELERATION SINGLE PASS OPEN WATER PROPELLER

TEST TECHNIQUE, J.G. Hoyt, H. Fireman, and M. Osbourne 45 OPTIMUM CIRCULATION DISTRIBUTIONS FOR SINGLE AND MULTI-COMPONENT

PROPULSORS, J.E. Kerwin, W.B. Coney, and C-Y Hsin 53 SESSION I I : OCEAN ENGINEERING

Chairman: Frank DeBord, J r . , O f f s h o r e Technology C o r p o r a t i o n , Esoondida, C a l i f o r n i a

OCEAN ENGINEERING COMMITTEE REPORT 65 WAVE INDUCED ORIFICE FLOWS, M.E. McCormick and M.J. G a l l e t 67

DYNAMIC BEHAVIOR OF A JACK-UP PLATFORM IN WAVES, A. C. Fernandes, J.M.A.

Vasconcelos, P. T. T. Esperanca, P. Barusco, J r . and S.H. Sphaier 77 MEASUREMENT OF THE FORCES ON A SLIGHTLY SUBMERGED CYLINDER, S. Hodges

and W.C. Webster 87 NON-LINEAR ANALYSIS OF TIME SERIES DATA, J. McDowell 99

SESSION I I I : RESISTANCE AND FLOW

Chairman: Edwin P. Rood, David T a y l o r Naval Ship R&D Center, Bethesda, Maryland

RESISTANCE AND FLOW COMMITTEE REPORT I l l THREE INDIRECT METHODS FOR THE DRAG CHARACTERIZATION OF ARBITRARILY ROUGH

SURFACES ON FLAT PLATES, P.S. G r a n v i l l e 117 A SEMI-EMPIRICAL APPROACH TO USING FIVE HOLE PITOT TUBES, J.C. Kuhn 127

IN OUR EXPERIENCE: SOME NEW METHODS AND TECHNIQUES, R.R. Young 139 MEASURING SHIP-MODEL RESISTANCE WITH A 'MINI' TOWING TANK, CC. Hsiung,

0. Cochkanoff, G. Q i a n y i and A. Hazzouri 145 ANALYTICAL APPROXIMATION FOR STEADY SHIP WAVES AT LOW FROUDE NUMBERS,

F. Noblesse 151 A TECHNIQUE FOR PERFORMING FLUORESCENT DYE FLOW STUDIES ON PROPELLER

BLADE SURFACES IN A MODEL BASIN, F.H. A s h c r o f t 165

SESSION I V : NEW FACILITIES AND TECHNIQUES

Chairman: David Murdey, N a t i o n a l Research C o u n c i l , I n s t i t u t e f o r Marine Dynamics, S t . John's, Newfoundland

REPORT OF COMMITTEE ON NEW FACILITIES AND TECHNIQUES 173 CALIBRATION OF TOWING TANK WAVEMAKING SYSTEM AT THE INSTITUTE FOR MARINE

DYNAMICS, I . D a t t a , and J. Murray 175 A MULTI MODE SEGMENTED WAVE GENERATOR FOR THE NRC HYDRAULICS LABORATORY,

M.D. M i l e s , P.H. L a u r i c h , and E.R. Funke 191 STEEP SHORT-CRESTED WAVES PRODUCED BY A SIMPLE THREE DIMENSIONAL WAVEMAKER,

M.P. T u l i n and A. K o l a i n i 203 DIRECTIONAL IRREGULAR WAVE GENERATOR DESIGN FOR SHALLOW WAVE BASINS,

D.G. Outlaw and M.J. B r i g g s 211 ACOUSTIC NOISE LEVELS IN THE HYDRONAUTICS SHIP MODEL BASIN, A. Goodman,

B.L. S l l v e r s t e l n and J.T. G o t t w a l d 217 CONCEPTION OF THE UNIVERSITY OF NEW ORLEANS SHIP OFFSHORE UNIVERSITY

LABORATORY, R. L a t o r r e • 227 THE INSTRUMENTATION AND DATA ACQUISITION SYSTEM AT NRC'S NEW MODEL TEST

FACILITY, C. N o r r i s , B. Gamberg and P. Thorburn 239 HYDRODYNAMIC DESIGN ASPECTS OF A LARGE CAVITATION CHANNEL, J.M. Wetzel,

C C S . Song, and R.E.A. Arndt 245

SESSION V: STEERING AND MANEUVERING

Chairman: Thomas Waters, David T a y l o r Naval Ship R&D Center, Bethesda, Maryland

REPORT OF THE STEERING AND MANEUVERING COMMITTEE 25 SWATH MANOEUVRABILITY RUNNING TRIM EFFECTS, W.C.E N e t h e r c o t e 259

STATUS OF MARCIS: THE MARINE COEFFICIENT IDENTIFICATION SYSTEM, T.L,

T r a n k l e 263 A CASE FOR THE SEPARATE DETERMINATION OF HYDRODYNAMIC CHARACTERISTICS OF

SHIP'S HULL, AND RUDDER, V. Asinovsky, A. Landsburg, and G. Hagen 271

SESSION V I : ICE TESTING

Chairman: Steven Jones, I n s t i t u t e f o r Marine Dynamics, N a t i o n a l Research C o u n c i l , S t . John's Newfoundland

ICE TESTING COMMITTEE REPORT 289 EFFECT OF ICE FLOE SIZE ON PROPELLER TORQUE IN SHIP-MODEL TESTS,

J-C T a t i n c l a u x 291 COMPARISON OF USCG POLAR CLASS ICEBREAKING PATTERNS: FULL SCALE TRIALS,

PHYSICAL MODEL TESTS AND ANALYTICAL PREDICTIONS, T. K o t r a s , D. Humphreys,

R. Ettema and A. Free 299 A STRENGTH INDEXER FOR MODEL ICE, D. Baker, G. Tiraoo, and C C . N o w i c k i 307

CANADA'S NEW ICE TANK, S.J. Jones 315 MODELLING THE BROKEN CHANNEL, G. Comfort, I.E. Glen, A. Keinonen and

J. G r i n s t e a d 321

SESSION V I I : SEAKEEPING

Chairman: J e f f r e y T. D i l l i n g h a m , The U n i v e r s i t y o f M i c h i g a n , Ann Arbor, Michigan

REPORT OF THE SEAKEEPING COMMITTEE 331 MEASUREMENT AND ANALYSIS OF MODEL EXPERIMENT DATA ON BOTTOM SLAMMING,

I . D a t t a 345 ERRORS DUE TO INTERACTIONS IN SEAKEEPING MODEL TESTS, S.B. Cohen 353

COMPARATIVE SEAKEEPING MODEL EXPERIMENTS, J. O'Dea and A.W. Troesch 359 MEASUREMENT OF SIX DEGREE OF FREEDOM MODEL MOTIONS USING STRAPDOWN

ACCELEROMETERS, M.D. M i l e s . . . ! 369 WAVE FORCE TESTING OF LARGE BASE STRUCTURES, E.E. Brogren and S.K.

C h a k r a b a r t i 377 TECHNIQUES IN DIRECTIONAL WAVE SPECTRAL ANALYSIS WITH APPLICATIONS FOR

THE SEAKEEPING BASIN, M. Dipper 385 DIRECTIONAL WAVE MEASUREMENTS FOR APPLICATION TO SHIP TRIAL ANALYSIS,

SESSION V I I I : CAVITATION

Chairman: Michael L. B i l l e t , A p p l i e d Research L a b o r a t o r y , The Pennsylvania S t a t e U n i v e r s i t y

CAVITATION COMMITTEE REPORT 409 CLOUD CAVITATION AND BUBBLE INTERACTION, G.L. Chahine 413

DREA PROPELLER CAVITATION RESEARCH, D.J. Noble, N.C. Sponagle and L.J.

Leggat ^21 ANALYSIS OF RECENT TIP VORTEX CAVITATION INCEPTION DATA, V.H. A r a k e r i ,

H. H i g u c h i and R.E.A. Arndt 431 CAVITATION SUSCEPTIBILITY OF OCEAN, AND LABORATORY WATER, Y.T. Shen

and S. Gowing '439 CAVITATION PHENOMENA IN JETS, H. L i n and J. Katz 451

CAVITATION OBSERVATIONS IN A TURBULENT SHEAR FLOW, T. J. O'Hern and

A. Acosta ^59 SESSION IX: HIGH SPEED VEHICLES AND SAILING

Chairman: Peter W. Broun, Stevens I n s t i t u t e o f Technology, Davidson L a b o r a t o r y , Hoboken, NJ

A RE-ANALYSIS OF PLANING BOAT PORPOISING STABILITY DATA, P.W. Brown INTERFERENCE EFFECTS BETWEEN PARALLEL PLANING SURFACES AT HIGH SPEED, D. S a v i t s k y

DEVELOPMENT OF THE UNO-SEAKEEP P.C. PROGRAM FOR PLANING HULL SEAKEEPING

ESTIMATION, J.R. Broussard, C. Wagner and R. L a t o r r e 477 SAILBOAT DRAG PREDICTION BASED ON REGRESSION OF A LARGE DATABASE,

A. W a r r i c k 487 STATUS OF THE WATER-PISTON PROPULSOR, R. Swanek, V.E. Johnson, J r 495

GROUP PHOTOGRAPH 505 LIST OF PARTICIPANTS 50 7

MINUTES OF THE BUSINESS MEETING OF THE 21st ATTC 513 PAST MEETINGS OF THE AMERICAN TOWING TANK CONFERENCE 515 AIMS AND ORGANIZATION OF THE AMERICAN TOWING TANK CONFERENCE 517

,469

.473

KEYNOTE ADDRESS

2 l 3 t AMERICAN TOWING TANK CONFERENCE

The M a r i t i m e Technology R e v o l u t i o n 1946-1986

VADM J. WEBBER, C h i e f Engineer, U.S. Navy Washington, D.C. 20362

ABSTRACT: The address covers t h e p e r i o d 1946-1986, and touches on the tremendous achievements t h a t have taken place i n s u r -face s h i p s , submarines, and o t h e r marine v e h i c l e t e c h n o l o g y : The r e v o l u t i o n a r y development o f the t r u e h i g h speed subma-r i n e i n the SO's; t h e osubma-rdesubma-r-of-magnitude i n c r e a s e i n t a n k e r c a p a b i l i t i e s and v a s t i n c r e a s e s i n cargo s h i p c a p a b i l i t i e s as evidenced by t h e 33 knot SL-7'3 as w e l l as o t h e r c o n t a i n e r s h i p s , barge c a r r i e r s and r o l l - o n / r o l l - o f f s h i p s ; t h e development o f t h r e e t o t a l l y new s h i p concepts: t h e h y d r o f o i l , t h e h o v e r c r a f t and the SWATH s h i p and the serai-submersible. Also cov-ered are the developments necessary t o operate under severe weather and sea con-d i t i o n s ancon-d mention o f how t o w i n g tanks have played a major r o l e i n these a c h i e v e -ments .

ADDRESS: Good morning and welcome t o the 21st American Towing Tank Conference.

The ATTC f i r s t met i n Hoboken a t the Stevens I n s t i t u t e o f Technology i n 1938. Much has happened i n the i n t e r i m ; much t h a t we a l l can be very proud o f , p a r t i c u -l a r -l y c o n s i d e r i n g t h a t many peop-le a t t e m p t to p a i n t t h e technology o f s h i p s as " o l d " and t h e r e f o r e i n c a p a b l e o f p r o d u c i n g vast change.

I n the next 20 minutes I am g o i n g t o touch upon J u s t a l i t t l e o f what has hap-pened i l l t h e marine technology business over the l a s t 40 years o r so. I f you accept Webster's d e f i n i t i o n o f t h e word r e v o l u t i o n as "a t o t a l o r r a d i c a l change" then you must c r e d i t those o f us i n t h e marine technology i n d u s t r y w i t h c r e a t i n g r e v o l u t i o n a r y change i n t h e post-vjar y e a r s . V i r t u a l l y every one o f these changes i n v o l v e t h e t o w i n g tank community.

I am g o i n g t o speak b r i e f l y about a few s e l e c t e d areas o f marine technology t h a t are p a r t o f t h i s r e v o l u t i o n and a t the end I w i l l l i s t some o t h e r s t h a t might have been covered.

I w i l l d i s c u s s :

. Development o f t h e t r u e submarine . Cargo movement advances

. Three new s u r f a c e v e h i c l e s . Working a t sea i n a l l weather

c o n d i t i o n s . Energy savings

By the c o n c l u s i o n o f World War I I t h e pressures o f w a r f a r e had l e d t o t h e d e v e l -opment o f some very e f f e c t i v e submarines. These were i n f a c t submersible s u r f a c e s h i p s ; very capable ones b u t n e v e r t h e l e s s submersible s u r f a c e s h i p s . Tremendous s t r i d e s had been made t o i n c r e a s e t h e speeds t h a t they c o u l d achieve v;hen sub-merged; some were a b l e t o make speeds w e l l i n excess o f 20 k n o t s , b u t o n l y f o r a v e r y s h o r t p e r i o d o f time b e f o r e they had t o s u r f a c e and recharge t h e i r b a t t e r i e s . And when they were s u r f a c e d they became

v u l n e r a b l e . Even the development o f t h e s o h n o r k l e , which p e r m i t t e d b a t t e r y

r e c h a r g i n g from s h a l l o w depths, s t i l l l e f t these submersible s u r f a c e s h i p s t o o v u l n e r a b l e t o e v e r i n c r e a s i n g ASW c a p a b i l i -t i e s .

Navies wanted h i g h submerged speed combined w i t h a submarine t h a t was capable to prolonged submerged o p e r a t i o n . The c a p a b i l i t y f o r h i g h speed submerged opera-t i o n emerged from some s o p h i s opera-t i c a opera-t e d research and technology developments a t the Center h o s t i n g t h i s conference: The David T a y l o r Model Basin developed S e r i e s 58 submarine h u l l forms. They were proven on the ALBACORE which achieved t h e h i g h e s t submerged speed o f any submarine a t t h a t t i m e . One h a l f o f t h e g o a l was achieved. The o t h e r h a l f , came as a r e s u l t o f

a p p l y i n g t h e n u c l e a r p r o p u l s i o n technology t h a t had been proven f i r s t on the conven-t i o n a l l y c o n f i g u r e d NAUTILUS. The r e s u l conven-t was t h e SKIPJACK, t h e f i r s t t r u e submarine c o n f i g u r a t i o n i n a t r u l y m i l i t a r y sense — a submarine capable o f h i g h speed and p r o -longed submerged o p e r a t i o n (see F i g u r e 1 ) .

What has happened s i n c e i s , i n r e a l i t y , o n l y s l i g h t l y l e s s remarkable. The s i z e o f these t r u e submarines has

F i g u r e 1 F R O M S U B M E R S I B L E S U R F A C E S H I P S TO T H E T R U E S U B M A R I N E 1946 ' VsURFACE = 20 KT VSUBMERGED = 20 KT BATT./DIESEL POWER ALBACORE 1953 VsURFACE = 25 KT VsUBMERGED = 25tKT DIESEL/BAIT. 1959 SKIPJACK VsURFACE = 16 KT VsUBMERGED = 30tKT NUCLEAR POWER 1954 VSURFACE = 23 KT NUCLEAR POWER NAUTILUS S O U R C E ; J A N E S FIGHTING SHIPS

grown tremendously ( F i g u r e 2) and t h e i r o p e r a t i n g c a p a b i l i t i e s have i n c r e a s e d s i g n i f i c a n t l y — p a r t i c u l a r l y when r e l a t e d t o q u i e t n e s s o f o p e r a t i o n . The technology o f p r o p e l l e r q u i e t i n g , as w e l l as o t h e r a c o u s t i c t r e a t m e n t s , has achieved remarka-b l e l e v e l s o f success. I f c l a s s i f i c a t i o n r e s t r i c t i o n s d i d not prevent me from quan-t i f y i n g quan-these achievemenquan-ts, I am sure quan-t h a quan-t you would agree w i t h me t h a t what has been accomplished i n j u s t t h i s one area i s t r u l y a s t o n i s h i n g .

Towing tanks have played a l a r g e r o l e i n submarine h u l l form development as w e l l as maneuvering, c o n t r o l and p a r t i c u l a r l y p r o p e l l e r development. I t i s the l a t t e r area where, because o f t r e n d s i n submarine design and design r e q u i r e m e n t s , f a c i l i t i e s such as the New Large C a v i t a t i o n Channel a t t h e Model B a s i n , are needed.

The next area t h a t I w i l l touch upon i n t h e marine technology r e v o l u t i o n i s the v a s t i n c r e a s e s t h a t have been achieved i n the movement o f cargo over the oceans and seas o f the w o r l d .

I w i l l f i r s t deal w i t h the movement o f b u l k commodities such as o i l and then I w i l l cover the s h i f t t o " m o d u l a r i z a t i o n " (which covers c o n t a i n e r i z a t i o n , barges c a r r i e d aboard s h i p s , and what one might c a l l m u l t i - s e c t i o n - s h i p s ) •

When you l o o k a t the r e s u l t s a f t e r 40 years or so o f development and a p p l i c a t i o n I t h i n k t h a t you would have t o agree t h a t these advances f i t the d e f i n i t i o n o f "a t o t a l or r a d i c a l change."

The growth o f t a n k e r s has been t r u l y remarkable, as shown i n F i g u r e 3.

Compared t o the T-2 o f World War I I (which was r e a l l y a l a r g e t a n k e r f o r t h a t e r a ) , we have seen an e x p l o s i o n i n t a n k e r s i z e (and c a p a c i t y ) . From 50,000 t o 60,000 tons deadweight i n the mid-50s t o 200,000 deadweight tons i n the 60s t o , i n t h e l a t e 70s, the l a r g e s t s h i p ever b u i l t — t h e 556,000 deadweight ton SEAWISE GIANT. T h i s behemouth was 1500 f e e t l o n g , 226 f e e t wide and had a depth o f 98 f e e t . I t would take 4400 C5-A a i r p l a n e s t o l i f t t h a t amount o f cargo weight (and a q u i t e l a r g e t a n k e r t o c a r r y the r e q u i s i t e f u e l needed f o r the a i r c r a f t ) and move i t the l o n g d i s t a n c e s necessary t o reach the "market p l a c e . "

I f you assume a s l i g h t l y more common-s i z e d l a r g e t a n k e r — common-s a y 320,000 dead¬ -weight tons c a p a c i t y — t h e n you have a

r o u g h l y 2 0 - f o l d I n c r e a s e i n c a r r y i n g capa-c i t y as capa-compared t o the WW I I T-2.

Consider t h a t the crew s i z e on many o f these very l a r g e s h i p s i s 20 t o 25 men as compared t o the T-2 crew s i z e o f 35 men and you f i n d a change i n the number o f tons o f cargo c a r r i e d per man from 460 tons per man t o , 14,000 t o 15,000 tons o f cargo per man!

No m a t t e r how one views I t , these developments were i m p r e s s i v e . And, they n e c e s s i t a t e d e q u a l l y i m p r e s s i v e t e c h n o l o g y developments i n hydrodynamics as w e l l as a host o f o t h e r s h i p - r e l a t e d t e c h n o l o g i e s . F i g u r e 2 E V O L U T I O N OF T R U E S U B M A R I N E F i g u r e 3 B U L K C A R G O M O V E M E N T SKIPJACK ATTACK PERMIT ATTACK LAFAYETTE SSBN LOS ANGELES ATTACK TRIDENT SSBN 1959 19G2 19G3 1976 19B2 1946^ 1 6 , 5 0 0 D W T ISIifl _fa. 1980

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I n t h e non-bulk cargo w o r l d an e q u a l l y i m p r e s s i v e change o f events took p l a c e . C o n v e n t i o n a l break-bulk s h i p s w i t h t h e i r c o m p l i c a t e d masts and cargo booms have g i v e n way t o t h e c o n t a i n e r s h i p , and then t h e d i f f e r e n t k i n d s o f barge c a r r i e r s and r o l l - o n / r o l l - o f f s h i p s and t o what might be c o n s i d e r e d an end p o i n t i n t h e m o d u l a r i t y sense: t h e i n t e g r a t e d t u g barge concept (which i s r e a l l y a m u l t i -s e c t i o n -s h i p where the p r o p e l l i n g -s e c t i o n i s t o t a l l y s e p a r a b l e from the cargo c a r r y -ing s e c t i o n o f t h e s h i p ) .

The growth i n s i z e o f these s h i p s has been l e s s than t h a t f o r t h e t a n k e r s . But the tremendous achievement t h a t has r e s u l t e d i s t h e i r i n c r e a s e i n o p e r a t i n g speeds from t h e 10 k n o t s t o 15 knots a t the end o f WW I I t o speeds o f 25 knots (and, the achievements by SEA Land o f t h e 33 k n o t , h i g h c a p a c i t y SL-7 c o n t a i n e r s h i p s ) (see F i g u r e k).

Also worthy o f mention, i s t h e i n c r e a s e i n t h e u n l o a d i n g r a t e s f o r these d i f f e r e n t k i n d s o f s h i p s . Tonnage unloaded per hour f o r these new s h i p s i s two t o t h r e e ORDERS OF MAGNITUDE g r e a t e r than t h e i r WW I I c o u n t e r - p a r t s .

C e r t a i n l y these are " r a d i c a l changes!" Between t h e mid- 1950s and today, t h r e e t o t a l l y new marine s u r f a c e v e h i c l e concepts have been developed and e x p l o i t e d e i t h e r c o m m e r c i a l l y or by the m i l i t a r y . These a r e :

. H y d r o f o i l s . H o v e r c r a f t , and

Small waterplane area t w i n h u l l (SWATH) o r semi-submersibles. These t h r e e d i f f e r e n t types o f marine v e h i c l e s are as d i f f e r e n t from each o t h e r (and raonohulls) as f i x e d wing a i r c r a f t are from h e l i c o p t e r s .

The h y d r o f o i l concept, though worked on p e r i o d i c a l l y e a r l i e r i n t h e Century, r e a l l y began i t s development i n earnest d u r i n g t h e 1950's =

F i g u r e 4

B R E A K B U L K C A R G O M O V E M E N T

For t h e f i r s t s i x t o e i g h t years t h e p a r t i a l l y - s u b m e r g e d f o i l , h y d r o f o i l was the o n l y type under development. Then i n the e a r l y 60's t h e U.S. Navy, soon t o be f o l l o w e d by o t h e r n a v i e s , began develop-ment o f t h e f u l l y submerged f o i l hydro-f o i l , t o improve i t s seaway perhydro-formance and t o i n c r e a s e i t s speed p o t e n t i a l (see F i g u r e 5 ) .

Towing tanks played very I m p o r t a n t r o l e s i n f o i l development, t r a n s c a v i t a t i n g and s u p e r - c a v i t a t i n g p r o p e l l e r development and i n d e v e l o p i n g a s e r i e s which p e r m i t t e d f l e x i b i l i t y i n t h e s e l e c t i o n o f h y d r o f o i l h u l l forms.

The second new v e h i c l e concept was the h o v e r c r a f t - a i r cushion supported v e h i c l e s e i t h e r w i t h a f u l l s k i r t or w i t h two r i g i d s i d e w a l l s and a p a r t i a l s k i r t f o r w a r d and a f t , as shown i n F i g u r e 6.

These types o f v e h i c l e s presented t h e p o t e n t i a l f o r v e r y h i g h calm water speeds and, some improvements i n speed i n moder-ate weather. The f u l l y s k i r t e d h o v e r c r a f t (or the ACV) a l s o presented an a d d i t i o n a l i m p o r t a n t b i t o f p o t e n t i a l -- t h e a b i l i t y to be operated i n an amphibious mode over both l a n d and t h e sea.

The r o l e o f tanks i n t h e development of h o v e r c r a f t was s u b s t a n t i a l . I n p a r t i c -u l a r mane-uvering and c o n t r o l system d e s i g n as w e l l as c o n f i g u r a t i o n r e s i s t a n c e and p r o p u l s i o n o p t i m i z a t i o n n e c e s s i t a t e d i n n o -v a t i -v e , complex and comprehensi-ve model e x p e r i m e n t a l t e c h n i q u e s t o be developed.

The f i n a l new v e h i c l e concept s t a r t e d i t s development i n t h e l a t e 50's when o i l e x p l o r a t i o n l e d t o o f f s h o r e r e q u i r e m e n t s i n f a i r l y deep w a t e r s , where weather cond i t i o n s ooulcond make i t cond i f f i c u l t f o r cond r i l l -ing o p e r a t i o n s t o c o n t i n u e w i t h

c o n v e n t i o n a l types o f d r i l l s h i p con-f i g u r a t i o n s . T h i s v e h i c l e concept was t h e semisubmersible which has crude b l o c k l i k e lower h u l l s w i t h t h r e e or more c y l i n -d r i c a l columns e x t e n -d i n g upwar-d t o a w o r k i n g p l a t f o r m many f e e t above t h e calm water s u r f a c e . F i g u r e 5

H Y D R O F O I L S

F i g u r e 6 F i g u r e 8 G R O W T H IN C O N S T R U C T I O N O F H Y D R O F O I L S ,

H O V E R C R A F T

1970s

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SWftTH-About 10 years l a t e r the U.S. Navy s t a r t e d the development o f the Small Waterplane Area Twin H u l l ( o r SWATH) con-c e p t . T h i s con-concon-cept embodied mucon-ch more s t r e a m l i n e d lower h u l l s and s t r u t s which p e r m i t t e d e x c e p t i o n a l seaway performance at speeds up t o 30 k n o t s (see F i g u r e 7 ) .

Tanks played an immense r o l e i n t h e development o f both semi-submerged s h i p and SWATH t e c h n o l o g y . Seakeeping f a c i l i -t i e s were a b s o l u -t e l y e s s e n -t i a l n o -t o n l y i n d e v e l o p i n g c o n f i g u r a t i o n s but a l s o i n d e v e l o p i n g e s s e n t i a l design t o o l s f o r both semi-submersibles and SWATH s h i p s . A d d i t i o n a l l y , SWATH t e c h n o l o g y n e c e s s i -t a -t e d maneuvering f a c i l i -t i e s , r e g u l a r - tow-i n g tank t e c h n tow-i q u e s and p r o p e l l e r and c a v i t a t i o n f a c i l i t i e s .

The sum and substance o f a l l o f t h i s i s t h a t today t h e r e are more than 1800 o f these t h r e e new marine v e h i c l e concepts t h a t have been b u i l t f o r COMMERCIAL OR MILITARY use. O i l e x p l o r a t i o n s t a r t e d t o move o f f -shore i n the e a r l y 1950s. T h i s l e d t o a F i g u r e 7 S E M I - S U B M E R S I B L E S & S W A T H S H I P S LATE 1950s SEMI-SUBMERSIBLES L A T E 1960 SWATH s e r i e s o f v e h i c l e developments: the t e t h -ered barge; the so c a l l e d Jack-up where the w o r k i n g p l a t f o r m would be jacked up on t h r e e l e g s t h a t would r e s t on the bottom; m o d i f i e d monohull concepts w i t h a "moon p o o l " - an opening i n the bottom o f t h e h u l l through which the d r i l l r i g c o u l d extend and, o f course t h e semisubmersible d r i l l r i g concept t h a t I r e f e r r e d t o a moment ago.

These concepts have e v o l v e d t o c r e a t e the a b i l i t y t o d r i l l f o r o i l month i n and month out - r e g a r d l e s s o f weather and sea c o n d i t i o n s .

C o m p e t i t i v e pressures ( b o t h commer-c i a l and m i l i t a r y ) have engendered a commer- con-t i n u i n g con-t r e n d con-towards e x con-t e n d i n g con-t h e

performance c a p a b i l i t i e s o f many t y p e s o f s u r f a c e v e h i c l e s t o h i g h e r and h i g h e r sea s t a t e s .

The accompanying f i g u r e shows a some-what t y p i c a l n o r t h e r n l a t i t u d e w i n t e r . Wave h e i g h t i s shown as a f u n c t i o n o f time f o r a three-month p e r i o d d u r i n g a nominal w i n t e r (December t h r o u g h F e b r u a r y ) f o r the F i g u r e 9 A L L W E A T H E R W O R K I N G A T S E A THE PROBLEM GRID POINT 1 2 9 BB.e-N 2 4 . 0 ° W / n o 1 6 9 •

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l o c a t i o n shown. This happens t o be a place o f m i l i t a r y i n t e r e s t b u t i t i s n o t a l l t h a t d i f f e r e n t from what might be expected by o i l d r i l l i n g companies o p e r a t -i n g -i n the n o r t h e r n reaches o f t h e North Sea o r t h e G u l f o f Alaska.

The c o n t i n u i n g press t o operate i n a l l b u t t h e most severe o f sea c o n d i t i o n s has been t h e t h r e a d o f the many d e v e l o p -ments over t h e l a s t f o u r decades.

I n a d d i t i o n t o t h e Jack-up r i g , t h e semi-submersible and SWATH c o n f i g u r a t i o n s have i n h e r e n t c h a r a c t e r i s t i c s t h a t p e r m i t a l l weather performance. A l s o , t h e h y d r o -f o i l a l s o has t h i s c h a r a c t e r i s t i c . I n p a r t i c u l a r , t h e f u l l y submerged f o i l h y d r o f o i l has, i n f a c t , t h e s m a l l e s t r e l a -t i v e w a -t e r p l a n e area and has shown supe-r i o supe-r seaway pesupe-rfosupe-rmance when i n o p e supe-r a t i o n f o i l b o r n e . A summary o f these " a l l weather" v e h i c l e s i s shown i n F i g u r e 10.

Much work has a l s o gone i n t o making the h o v e r c r a f t o p e r a t e w e l l a t speed i n heavy seas; t o a p o i n t , t h a t i s i n moder-ate seas t h e e f f o r t s have been s u c c e s s f u l , but more work has t o be done i n t h i s a r e a .

I n t h e l a s t decade, due t o t h e d r a s t i c i n c r e a s e i n energy p r i c e s , t h e r e has been a s u b s t a n t i a l investment i n ways t o reduce f u e l consumption. I n t h e marine v e h i c l e business t h i s investment as focused on two p r i m a r y areas; machinery developments towards l e s s energy consump-t i o n and g r e a consump-t e r e f f i c i e n c y , and h u l l form and p r o p u l s o r designs t o achieve g r e a t e r f u e l economy. I w i l l deal today w i t h t h e l a t t e r group.

Regarding h u l l forms, d e s i g n t o o l s and f a c i l i t i e s have been p u t t o work i n o r d e r t o develop c o n f i g u r a t i o n s t h a t w i l l p e r m i t t h e b a s i c f u n c t i o n s o f t h e s h i p t o be performed i n t h e most e f f i c i e n t manner. I n a d d i t i o n t o t h e use o f bow bulbs t o reduce wave making energy, we now see t h e emergence o f " s t e r n b u l b s , " asymmetric s t e r n s , and c o k e - b o t t l e lower h u l l s on SWATH s h i p s and o t h e r schemes shown i n F i g u r e 1 1 . F i g u r e 10 ALL W E A T H E R WORKIMG A T S E A

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We have a l s o encountered myriad p r o -p u l s i o n conce-pts, some embodying o n l y t h e p r o p u l s o r i t s e l f and o t h e r s i n v o l v i n g t h e a f t e r p a r t o f t h e s h i p , o r t h e a d d i t i o n o f c o u n t e r s w i r l d e v i c e s , i n a d d i t i o n t o t h e p r o p u l s o r . I n s p i t e o f t h e r e c e n t drop i n f u e l p r i c e s , t h i s t r e n d w i l l c o n t i n u e .

I n the past few minutes I have covered f o u r o f a l a r g e r number o f areas t h a t com-p r i s e t h e r a d i c a l change t h a t has taken p l a c e i n marine t e c h n o l o g y i n t h e past 40 y e a r s . I n a d d i t i o n , t h e f o l l o w i n g areas deserve mention.

Undersea v e h i c l e s have gone t h r o u g h t h e i r own r e v o l u t i o n , f o r both commercial and r e s e a r c h purposes. The r e c e n t adven-t u r e o f adven-t h e s u b m e r s i b l e ALVIN, and i adven-t s r o b o t i c t e t h e r e d - v e h i c l e JASON, and t h e i r e x p l o r a t i o n down i n t o t h e i n s i d e o f t h e TITANIC i s t r u l y an achievement o f v a s t p r o p o r t i o n s . S i m i l a r l y , t h e t e t h e r e d v e h i c l e s t h a t were used t o f i n d t h e I n d i a n a i r l i n e r t h a t went down o f f I r e l a n d l a s t year are v e h i c l e s t h a t can be very p r e -c i s e l y -c o n t r o l l e d and whi-ch -can perform u s e f u l f u n c t i o n s w h i l e a t t h e end o f t e t h -ers m i l e s l o n g .

S e r v i c e c r a f t such as t u g boats and the o t h e r new types o f v e h i c l e s t h a t came i n t o being as a r e s u l t o f o f f - s h o r e o i l e x p l o i t a t i o n have changed d r a s t i c a l l y . A 1500 t o 2000 horse power t u g was n o t a b l e i n t h e HQ's; we now have some ocean g o i n g tugs t h a t have 25,000 horse power! And t h e r e are thousands o f s h i p s i n t h i s f l e e t of o f f - s h o r e s u p p o r t c r a f t .

Ship i c e o p e r a t i o n s f o r p r i m a r i l y com-m e r c i a l purposes have engendered t h e deve-lopment o f v e h i c l e s and p l a t f o r m s which can w i t h s t a n d t h e r i g o r s o f h i g h l a t i t u d e o p e r a t i o n s as w e l l as s p e c i a l i z e d " i c e t a n k " developments.

D u r i n g these f o u r decades t h e f i s h i n g i n d u s t r i e s o f t h e w o r l d have gone t h r o u g h tremendous change as evidenced by t h e tuna c l i p p e r s which developed i n t h i s c o u n t r y F i g u r e 11 H Y D R O D Y N A M I C - E N E R G Y S A V I N G S HULL F0RIV1S • I N C R E A S E D EPF. HULL F O R M S • B O W B U L B S • S T E R N B U L B S • A S Y M M E T R I C S T E R N S • " C O K E - B O T T L E " H U L L S I S W A T H I • S T E R N T U N N E L S PROPULSION S Y S T E M S • LOW RPM PROPS • C O N T R A R O T A T I N G P R O P S • V A N E W H E E L PROPULSION • PARTIAL D U C T & PROP • C O U N T E R - S W I R L PROP • O V E R L A P P I N G PROPS • R U D D E R / B U L B - FIN S Y S T E M S

and f i s h i n g f a c t o r y s h i p s from o t h e r c o u n t r i e s . Even f i s h i n g t r a w l s a r e now b e i n g developed i n t o w i n g t a n k s .

T h i s meeting would n o t be complete w i t h o u t mention o f y a c h t s ; t h e l i t e r a l e x p l o s i o n o f the yacht business i n t h e post-war years i s obvious t o anyone f l y i n g near a coast on a summer weekend. And, I should mention perhaps t h e l a r g e s t c h a l -lenge o f a l l i n t h e y a c h t i n g w o r l d : t h e r e c o v e r y o f t h e America's cup.

What does a l l o f t h i s mean us? I n t h e l a s t 40 years many new t o w i n g tank f a c i l i t i e s have been b u i l t . I n a d d i t i o n , new and d i f f e r e n t types o f f a c i -l i t i e s have come i n t o being such as seakeeping f a c i l i t i e s , p l a n a r motion mechanisms, r o t a t i n g arm f a c i l i t i e s , and g r e a t l y i n c r e a s e d c a p a c i t y c a v i t a t i o n channels. These, as w e l l as t h e t r a d i -t i o n a l -t o w i n g -tanks and c i r c u l a -t i n g wa-ter channels, have a l l played an a b s o l u t e l y v i t a l r o l e i n the m a r i t i m e r e v o l u t i o n t h a t has taken p l a c e .

These f a c i l i t i e s have been used i n t h e i r u s u a l way o f o b t a i n i n g e x p e r i m e n t a l v e r i f i c a t i o n o f t h e c h a r a c t e r i s t i c s , e t c . f o r p a r t i c u l a r v e h i c l e designs. They have a l s o played an even more i m p o r t a n t r o l e : t h a t o f d e v e l o p i n g t h e t e c h n i c a l b a s i s f o r e x p l o i t a t i o n o f computer-aided a n a l y s i s t o o l s , computer-aided design t o o l s based on e m p i r i c a l a n a l y s i s o f broad data bases,

and v a l i d a t i o n o f t h e development o f b a s i c computer hydrodynamic design and a n a l y s i s codes.

I n F i g u r e 12 t h a t you see b e f o r e you I have t r i e d t o i n d i c a t e q u a l i t a t i v e l y t h e r o l e played by d i f f e r e n t k i n d s o f t o w i n g tank f a c i l i t i e s i n t h e f i v e areas t h a t I have covered i n t h i s p r e s e n t a t i o n .

The r o l e p l a y e d by you who have been i n v o l v e d has been i n n o v a t i v e and produc-t i v e . Much has been a c h i e v e d , and produc-t h e r e i s much more t o be achieved i n t h e f u t u r e .

I don't t h i n k t h a t I have t o t e l l any of you t h a t t h e m a r i t i m e i n d u s t r y w o r l d -wide i s on hard times today, and has been f o r t h e l a s t few y e a r s . I n 1946 t i m e s were n o t v e r y good e i t h e r . The war had come t o an end. There was a g l u t o f a v a i l a b l e s h i p p i n g . The w o r l d economy was i n a s t a t e o f u n d e r s t a n d a b l e t u r m o i l . But a l l o f what I have covered w i t h you t h i s morning began t o u n f o l d as t h e years passed. A m a r i t i m e r e v o l u t i o n took place and I doubt t h a t anyone oould have p r e -d i c t e -d t h e -d i f f e r e n t an-d m u l t i - f a c e t e -d courses t h a t i t t o o k . But t h e r e v o l u t i o n DID take p l a c e .

A l l o f us should be proud t o have been p a r t o f i t and we should be c o n f i d e n t t h a t we w i l l be a b l e t o c o n t r i b u t e t o i t s c o n t i n u a t i o n i n t h e years t o come. Thank you. F i g u r e 12

R O L E OF " T A N K E R Y " IN V A R I O U S

A R E A S OF M A R I T I M E T E C H N O L O G Y

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PARTICIPANTS OF THE 2 l 3 t AMERICAN TOWING TANK CONFERENCE 5, 6, 7 AUGUST 1986

ABKOWITZ, M., Massachusetts I n s t i t u t e o f Technology, Cambridge, MA U.S.A ALAEZ, J.A., Canal De E x p e r l e n c i a s Hydrodlnamicas, Madrid, SPAIN

ANDERSON, K., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. ANDREWS, M.D., Naval Research L a b o r a t o r y , Washington, D.C. U.S.A

ANTHONY, D., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. ARAKERI, v., S t . Anthony F a l l s H y d r a u l i c s Lab., M i n n e a p o l i s , MN U.S.A. ASHBY, R., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. ASHCROFT, F.H., U n i v e r s i t y o f M i c h i g a n , Ann Arbor, MI U.S.A. ASINOVSKY, v., John J. McMullen Assoc., I n c . , A r l i n g t o n , VA U.S.A. BACHMAN, R., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. BAGNELL, D. G., 12213 Maycheok Lane, Bowie, MD U.S.A.

BAILOR, J., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. BAKER, D., M e l v i l l e S h i p p i n g , L t d . , Ottawa, O n t a r i o , KIR 7S8 CANADA BARNELL, A,, David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. BARUSCO, P., PETROBRAS, Rio De J a n e i r o , BRAZIL

BELL, R., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. BHATTACHARYYA, R., U.S. Naval Academy, A n n a p o l i s , MD U.S.A.

BILLET, M., A p p l i e d Research Laboratory/Penn S t a t e U, S t a t e C o l l e g e , PA U.S.A. BLAKE, W., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A.

BLANTON, J,, David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. BRESLIN, J., Stevens I n s t i t u t e o f Technology, Hoboken, NJ U.S.A. BROCKETT, T.E., U n i v e r s i t y o f M i c h i g a n , Ann Arbor, MI U.S.A.

BROGREN, E., Chicago B r i d g e and I r o n I n d u s t r i e s , I n c . P l a i n f i e l d , I L U.S.A. BROWN, E.M., U.S. Coast Guard Academy, New London, CT U.S.A.

BROWN, J., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A.

BROWN, P. W., Stevens I n s t i t u t e o f Technology, Davidson Lab. Hoboken, NJ U.S.A. CALLANEN, S., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A.

CHANG, P e t e r , David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. CHEN, B., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. CHORNEY, S.J., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. CIESLOWSKI, D., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. COAKLEY, S., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A.

CODER, D., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. CONRAD, R., Naval Sea Systems Command, Washington, D.C. U.S.A. COUCH, R.B., U n i v e r s i t y o f M i c h i g a n , Ann Arbor, MI U.S.A. COX, B., Hydrodynamics Research A s s o c i a t e s , R o c k v i l l e , MD U.S.A. COX, G., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. GUMMING, R.A., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. CURPHEY, R., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. CUSANELLI, D., David T a y l o r Naval Ship R&D Center, Bethesda, U.S.A. DAI, C , David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. DALZELL, J . , David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. DATTA, I . , N a t i o n a l Research C o u n c i l , I n s t i t u t e f o r Marine Dynamics,

St.John's, NF, CANADA

DAY, W., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. DEBORD, F., O f f s h o r e Technology C o r p o r a t i o n , Escondida, CA U.S.A. DEMPSEY, E., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. DEVONES, R., SAAB Systems, I n c . , S e a t t l e , WA U.S.A.

DIPPER, M., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. DOBAY, G., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. DUNCAN, J., Flow Research, S i l v e r S p r i n g , MD U.S.A.

DURKIN, J.M., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. EDA, H., Stevens I n s t i t u t e o f Technology, Davidson L a b o r a t o r y , Hoboken,

NJ U.S.A.

ENGLE, A., Naval Sea Systems Command, Washington, D.C. U.S.A. ETTER, R.J., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. FEIN, J. A., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. FELDMAN, J., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. FERNANDES, A.C., I n s t i t u t o de Pesquisas Technologioas, Cidade U n i v e r s i t a r i a ,

Sao Paulo, BRAZIL

FIREMAN, H., Naval Sea System Command, Washington, D.C. U.S.A. FISH, S., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. FISHER, S., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. FOLEY, E., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. FREE, A., ARCTEC, I n c . , Columbia, MD U.S.A.

FUHS, D., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A.

GEARHART, W. , A p p l i e d Research Laboratory/Penn S t a t e U, S t a t e C o l l e g e , PA U.S.A.

GERSTEN, A., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. GOODMAN, A., Tracor H y d r o n a u t i c s , I n c . , L a u r e l , MD U.S.A.

GORDON, J . , David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. GOSPODNETIC, D., Dominis G r a p h i s , L t d . , V a n l e r , O n t a r i o KIL 7H8 CANADA GOTTWALD, J.T., Tracer H y d r o n a u t i c s , L a u r e l , MD U.S.A.

GRANVILLE, P., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. GROVES, N., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. HAGEN, G., Designers & P l a n n e r s , A r l i n g t o n , VA U.S.A.

HARPER, H.D., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. HAWKINS, S., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. HENDRIX, D., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A.

HETTCHE, L.R., A p p l i e d Research Laboratory/Penn S t a t e U,State C o l l e g e , PA U.S.A. HILL, J., U.S. Naval Academy, A n n a p o l i s , MD U.S.A.

HODGES, S., U n i v e r s i t y o f C a l i f o r n i a , B e r k e l e y , CA U.S.A.

HONG, Y., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. HOUGH, J . , Naval Sea Systems Command, Washington, D.C. U.S.A. HOYT, J . , San Diego S t a t e U n i v e r s i t y , San Diego, CA U.S.A. HOYT, J . , David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. HSIUNG, C C , T e c h n i c a l U n i v e r s i t y o f Nova S c o t i a , H a l i f a x , N.S. CANADA HSU, C C , David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. HUANG, T.T., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A.

HUNT, L., Naval S t u d i e s Board, N a t i o n a l Academy o f Scienoes, Wash., D.C. U.S.A. JESSUP, S., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A.

JOBST, W., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. JOHNSON, B., U.S. Naval Academy, A n n a p o l i s , MD U.S.A.

JOHNSON, R.A., A p p l i e d Research Laboratory/Penn S t a t e U,State C o l l e g e , PA U.S.A. JONES, S.J., N a t i o n a l Research C o u n c i l , I n s t i t u t e f o r Marine Dynamics

St. John's NF CANADA ' KAPLAN, P., V i r g i n i a P o l y t e c h n i c I n s t i t u t e and S t a t e U n i v e r s i t y , B l a o k s b u r g ,

V A U • S • A •

KARAFIATH, C , David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. KATZ, J . , Purdue U n i v e r s i t y , West L a f a y e t t e , IN U.S.A.

KELLER, J . C , U.S. Coast Guard, Washington, D.C U.S.A.

KIM, K.H., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. KIM, S. H., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. KIRKMAN, K., Naval A r c h i t e c t s & Marine Engineers, A r l i n g t o n , VA U.S.A.

KOLAINI, A., U n i v e r s i t y o f C a l i f o r n i a , Santa Barbara, CA U.S.A. KOPP, P., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. KRESIC, M., John J . McMullen A s s o c i a t e s , I n c . , New York, NY U.S.A. KUHN, J . C , O f f s h o r e Technology Corp., Escondido, CA U.S.A.

LANGE, W., MTS Syterns Corp., M i n n e a p o l i s , MN U.S.A.

LATORRE, R., U n i v e r s i t y o f New O r l e a n s , New O r l e a n s , LA U.S.A. LAURICH, P.H., N a t i o n a l Research C o u n c i l , Ottawa, O n t a r i o CANADA LEE, C , O f f i c e o f Naval Research, A r l i n g t o n , VA U.S.A

LEE, D., Newport News S h i p b u i l d i n g , Newport News, VA U.S.A. LEE, H.C, U.S. Coast Guard, Washington, D.C. U.S.A.

LEE, J . , David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. LEE, W.T., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A LEE, Y.T., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. LIN, W-C, David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. LINCOLN, W., U.S. Coast Guard R&D Center, Avery P o i n t , G r o t o n , CT U.S.A. LINDENMUTH, W., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A LIU, H.L., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. LUNDY, W., U.S. Coast Guard, Washington, D.C. U.S.A.

MARTIN, M., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. MCCARTHY, J.H., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. MoCREADY, J . , David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. MCCREIGHT, W.R., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. MELLISH, R., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. MESSALLE, R., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. MEYER, J.R., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. MILES, M. D., N a t i o n a l Research C o u n c i l , Ottawa, O n t a r i o CANADA MORGAN, W.B., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. HOTTER, L., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. MURDEY, D.C, N a t i o n a l Research C o u n c i l , I n s t i t u t e f o r Marine Dynamics,

S t . John's, NF CANADA

NAGLE, T., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. NGUYEN, P., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. NOBLE, D.J., Defense Research E s t a b l i s h m e n t A t l a n t i c , Dartmouth, N.S. CANADA NOBLE, P., A r o t e c , Columbia, MD U.S.A.

NOBLESSE, F., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. NORRIS, C , N a t i o n a l Research C o u n c i l , I n s t i t u t e f o r Marine Dynamics,

S t . John's, NF CANADA 510

OAKES, M., J.J. McMullen A s s o c i a t e s , A r l i n g t o n , VA U.S.A.

O'DEA, J., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. OUTLAW, D.G., Dept. o f t h e Army, Corps o f Engineers, V i c k s b u r g , MS U.S.A. PARASKEVAS, N.M., The David T a y l o r Naval Ship R&D Center, Bethesdsa, MD U.S.A. PIRRONE, M., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A.

PLATZER, G.P., Naval Sea Systems Command, Washington, D.C. U.S.A. REED, A., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. RODDAN, G., B.C. Research, Vancouver, B.C. CANADA

ROOD, E., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. SANDBERG, W., Naval Sea Systems Command, Washington, D.C. U.S.A. SANTORE, G.L., ORI, I n c . , A r l i n g t o n , VA U.S.A.

SAVITSKY, D., Stevens I n s t i t u t e o f Technology, Davidson Lab., Hoboken, NJ U.S.A. SCHWARZENBERG, D., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. SCHOTT, C , David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. SEIBOLD, F., M a r i t i m e A d m i n i s t r a t i o n , Washington, D.C. U.S.A. SELLERS, F., MPR A s s o c i a t e s , Washington, D.C. U.S.A.

SHEN, Y.T., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. SHERMAN, P.M., John J. McMullen Assoc., A r l i n g t o n , VA U.S.A. SILVER, A., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. SILVERSTEEN, B., Traoor H y d r o n a u t i c s , I n c . , L a u r e l , MD U.S.A. SMITH, S., U.S. Coast Guard, Washington, D.C. U.S.A.

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SOUDERS, W., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A.

SPONAGLE, N.C, Defense Research E s t a b l i s h m e n t A t l a n t i c , Dartmouth, NS, CANADA STENSGAARD, C , B.C. Research, Vancouver, BC, CANADA

STENSON, R.J., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. SUHOKE, R., DANTEC E l e c t r o n i c s , A l l e n d a l e , NJ 071)01 U.S.A.

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WALDEN, D.A., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. WALLENDORF, L., U.S. Naval Academy, A n n a p o l i s , MD U.S.A.

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WATERS, R.T., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. WETZEL, J.M., S t . Anthony F a l l s H y d r a u l i c Lab., M i n n e a p o l i s , MN U.S.A. WHITE, J.A., U.S. Coast Guard, Washington, D.C. U.S.A.

WILSON, M., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. WILSON, R.A., David T a y l o r Naval Ship R&D Center, Bethesdsa, MD U.S.A. WISLER, B., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. WOOD, J., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. YANG, C , David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. YIM, B., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. YOUNG, R., U.S. Coast Guard R&D Center, Avery P o i n t , Groton, CT U.S.A. ZARNICK, E., David T a y l o r Naval Ship R&D Center, Bethesda, MD U.S.A. ZSELECZKY, J . , U.S. Naval Academy, A n n a p o l i s , MD U.S.A.

MINUTES OF THE 21ST ATTC BUSINESS SESSION

The business session was c a l l e d t o order by Dr. W i l l i a m B. Morgan, Chairman, at 11:20 AM on Thursday, August 5, 1986.

Since the chairman o f the ATTC i s the N o r t h and South America Area

R e p r e s e n t a t i v e t o the ITTC, business items r e l a t i n g t o t h e ITTC were conducted f i r s t . Dr. Morgan made the f o l l o w i n g announcements:

1. I n v i t a t i o n s f o r the Oot 198? ITTC meeting i n Kobe, Japan had been sent o u t .

2. V o l u n t e e r s a r e needed f o r t h e t e c h n i c a l committees.

3. The ITTC Ex ec ut iv e Committee requested t h a t the 1993 meeting be h e l d i n B r a z i l . The ATTC would have t o support t h i s endeavor a l t h o u g h i t i s not c l e a r now e x a c t l y what t h i s support means.

Antonio Fernandes from I n s t i t u t o de Pesquisas Technologioas (IPT) i n Sao Paulo, B r a z i l s a i d he f e e l s they can host the 20th ITTC i n 1993.

I t was moved and unanimously approved t h a t t h e ATTC w i l l support IPT a t t h e 1993 ITTC meeting i n B r a z i l .

The Chair was t u r n e d over t o Dr. D a n i e l S a v i t s y f o r the e l e c t i o n o f t h e North and South America Area R e p r e s e n t a t i v e t o the ITTC. Normally the r e p r e s e n -t a -t i v e serves f o r -two -terms. The nomina-ting commi-t-tee nomina-ted Dr. Morgan s i n c e he has o n l y served one term. There were no o t h e r nominations from t h e f l o o r . Dr. Morgan was unanimously r e - e l e c t e d as the N o r t h and South America Area R e p r e s e n t a t i v e t o t h e ITTC f o r a t h r e e year term ending i n I 9 8 9 . Dr. S a v i t s k y then expressed thanks t o Dr. Morgan and h i s s t a f f f o r a g r e a t conference.

The ATTC E x e c u t i v e Committee r e c e i v e d an i n v i t a t i o n f o r t h e next meeting from t h e I n s t i t u t e f o r Marine Dynamics (IMD) i n S t . John's, Newfoundland. There were no o t h e r i n v i t a t i o n s from the f l o o r and the i n v i t a t i o n was u n a n i -mously accepted. Mr. David Murdey from IMD i s the Chairman o f the 22nd ATTC and w i l l form a new e x e c u t i v e committee t o prepare f o r the next conference i n 1989.

PAST MEETINGS OF THE AMERICAN TOWING TANK CONFERENCE I s t Ik-15 A p r i l 1938 2nd 19-20 Sep 1939 3rd iHth Nov 1940 n t h l U t h Nov 1941 5th 29-30 Sep 1943 6th 12-13 Nov 1946 7 t h 7-8 Oot 1947 8 t h 11-13 Oct 1948 9th 11-14 Sep 1950 10th 4-6 May 1953 11th 12-14 Sep 1956 12th 31 Aug-2 Sep 1959 13th 5-7 Sep 1962 14th 9-11 Sep 1965 15th 25-28 June 1968 16th 9-13 Aug 1971 17th 18-20 June 1974 18th 23-25 Aug 1977 19th 9-11 J u l y 1980 20th 2-4 Aug 1983 21st 5-7 Aug 1986

Experimental Towing Tank Hoboken, New Jersey

I s t day - R e c e i v i n g Ship B u i l d i n g Navy Yard, Washington, D.C. 2nd day - David T a y l o r Model Basin Waldorf A s t o r i a

New York, NY Waldorf A s t o r i a New York, NY

David T a y l o r Model Basin Washington, D.C. Experimental Towing Tank Hoboken, New Jersey

Newport News S h i p b u i l d i n g & Dry Dock Co., Newport News, V i r g i n i a

The U n i v e r s i t y o f Michigan Ann Arbor, Michigan

N a t i o n a l Research C o u n c i l o f Canada Ottawa, Canada

Massachusetts I n s t i t u t e o f Technology Cambridge, Massachusetts

David T a y l o r Model Basin Washington, D.C.

The U n i v e r s i t y o f C a l i f o r n i a B e r k e l e y , C a l i f o r n i a

The U n i v e r s i t y o f Michigan Ann Arbor, Michigan

Webb I n s t i t u t e o f Naval A r c h i t e c t u r e Glen Cove, New York

N a t i o n a l Research C o u n c i l o f Canada Ottawa, Canada

I n s t i t u t o de Pesquisas Tecnologicas Sao Paulo, B r a z i l

C a l i f o r n i a I n s t i t u t e o f Technology Naval Undersea Center

Pasadena, C a l i f o r n i a U.S. Naval Academy A n n a p o l i s , Maryland The U n i v e r s i t y o f Michigan Ann Arbor, Michigan Davidson L a b o r a t o r y Hoboken, New Jersey

N a t i o n a l Academy o f Sciences Washington, D.C.