NEL/REPORT 1390

OGE1 LY0d3u/13N

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ae —he

SEA NOISE VS NEAR AND DISTANT WAVE HEIGHT
AND WIND SPEED

Correlation of measurements made in deep, open-ocean areas
of the Northeast Pacific

W. L. Frisch ° Research and Development Report ° 11 July 1966
U. S. NAVY ELECTRONICS LABORATORY, SAN DIEGO, CALIFORNIA

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DISTRIBUTION OF THIS DOCUMENT IS UNLIMITED

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0 0301 0040539 5

PROBLEM

Within a general investigation of the properties, mechanisms,
and origins of low-frequency underwater ambient noise, examine
the relationships, if any, between deep, open-ocean ambient sea
noise, in the frequency range from 10 to 400 c/s, and both near
and distant wave height and wind speed.

RESULTS

ils Sound pressure spectrum level is influenced by wave height
and wind speed at both ends of the frequency range from 10 to
400 c/s; greatest dependence is in the 160-to-400-c/s portion.

2s Ambient-noise levels in the range from 32 to 160 c/s are the
least influenced by near and distant wave height.

Bo No dependence of ambient-noise levels on distant wave-
height fluctuation was observed for periods during which local
wave-height conditions were moderate and uniform.

RECOMMENDATIONS

i. Extend the analysis of the noise data acquired in this project
to ambient noise below 10 c/s.

ADMINISTRATIVE INFORMATION

Work was performed under SF 101 03 15, Task 8119 (NEL
L20461). The report covers work from 1 July 1965 to 1 June 1966
and was approved for publication 11 July 1966.

CONTENTS

INTRODUCTION ... page 5
METHODS ...8
RESULTS... 13

CONCLUSIONS ... 23

ILLUSTRATIONS

1 Sea-noise spectra for various sea states ...page 6

2 Ambient-noise spectra, summarizing results and conclusions
concerning spectrum shape and level and probable sources
and mechanisms of the ambient noise in various parts of
the spectrum between 1 c/s and 100 kc/s... 7

3 Portion of wind-wave analysis from Fleet Numerical Weather
Facility, Monterey, California, showing wave-height
contours... &

4 Typical sections of records of broadband ambient-noise
levels ...10

5 Distribution of maximum wave heights. ..12

6 Variation with frequency of coefficient of correlation between
sound pressure spectrum level and cumulative maximum
wave heights, all stations ...14 - 15

7 Monthly average sound pressure level at 20-c/s midband
frequency, and monthly average local wave height .. .16

8 Variation with frequency of coefficient of correlation between

sound pressure spectrum level and cumulative maximum
wave heights for periods of highest and lowest frequency
of occurrence of 20-c/s signal, all stations ...17 - 18

9 Variation with frequency of coefficient of correlation between
sound pressure spectrum level and maximum wave heights
for periods during which wave height at source was less
than 3 feet ...19

ILLUSTRATIONS (Continued)

10 Variation with frequency of coefficient of correlation
between sound pressure spectrum level and wind
speed. ..page el

11 Ambient noise versus frequency at station D... 22

REVERSE SIDE BLANK

INTRODUCTION

The classic curves of Knudsen’ (fig. 1) and Wenz” (fig. 2)
show the relationship between ambient noise in the ocean and
storm or wind activity in terms of wind speed or wave height
measured directly, or very nearly directly, above the area in
which the sound measurements are made. The Knudsen curves,
which treat the frequency range from about 100 c/s to 10 ke/s,
describe a consistent dependence of noise level on wind speed and
wave height. The Wenz curves treat frequencies down to 1 c/s,
and reflect the lack of such dependence below 100 c/s in much of
the experimental data.

It is not well known what relationships, if any, exist between
ambient-noise levels in the very-low frequencies and storm activ-
ity occurring at great distances from the hydrophone. The hydro-
phones that provided data utilized for this report were located in
deep ocean areas providing conditions favorable for the reception
of any low-frequency noise propagated from distant storm centers.

In a pilot study® ambient-noise levels were considered to be
related to the action of winds at the interface. Wind fields over
increasing areas to as far as 1400 nautical miles from the hydro-
phone were considered.

In general, the trends suggested a dependence of ambient
noise on wind speed in both the high and low ends of the frequency
range considered. The dependence decreases with range, but the
decrease is smaller at frequencies below 25 c/s. Anomalous
results were noted at 20 c/s.

This study examines the dependence of ambient noise in the
frequency range of 10 to 400 c/s on wave height. Wave height is
measured both in very near proximity to the hydrophone and at
great distances. In addition, changes in noise level are compared
with changes in wind speed measured in moderate proximity to the
hydrophone.

SOUND PRESSURE SPECTRUM
LEVEL, DB RE 0.0002 DYNE/CM2

70

PSU

50 SS

CTH

TTS ITT

HERS SS

. Bas! NS Be
4

“CT aS

7 rons 0.05 0.1 0.2 0.5 ] 5 10 20 50 100

FREQUENCY, KC/S

Figure 1. Sea-noise spectra for various sea states.

EARTHQUAK ES AND EXPLOSIONS

BIOLOGICS INTERMITTENT AND
—PRECIPITATION— LOCAL EFFECTS
SHIPS, INDUSTRIAL
ACTIVITY
SEA Cheeses

TURBULENT-PRESSURE
SURFACE FLUCTUATIONS

WAVES, ete ae
SECOND. ™ OCEANIC TRAFFIC. PREVAILING NOISES

aeiee BUBBLES AND SPRAY
~ (SEISMIC (SURFACE AGITATION)

BREECIIS
BACKGROUND)

120

WIND-DEPENDENT BUBBLE
AND SPRAY NOISE

_jj
\
= \ _____ USUAL TRAFFIC NOISE, DEEP
BEA: 280 i = WATER
= =
> © win) USUAL TRAFFIC NOISE, SHALLOW
pe \ WIND FORCE WATER
ne & Seo) | EXTRAPOLATIONS
2S LIMITS OF PREVAILING NOISE
ae) THERMAL NOISE
5S 40
wo Ww LOW-FREQUENCY, VERY-
ee ~ SHALLOW-WATER WIND
= ony DEPENDENCE
= moma HEAVY TRAFFIC NOISE
a —-— HEAVY PRECIPITATION
0
11s GENERAL PATTERN OF NOISE
1OTe au) —-—-— FROM EARTHQUAKES AND
AGITATION EXPLOSIONS
~20
1 10 10? 10 3 10” 10°

FREQUENCY, C/S

Figure 2. Ambient-noise spectra, summarizing results and conclusions concerning
spectrum shape and level and probable sources and mechanisms of the ambient noise in
various parts of the spectrum between I c/s and 100 kc/s.

METHODS

The noise data originated from four hydrophones located at
depths greater than 500 fathoms. The four hydrophone stations
were selected to sample the Pacific coastal area from Washington
to Southern California. They are designated A, B, C, and D in
order from north to south. The larger part of the analysis was
done on station A, which provided ambient-noise data with a nom-
inal amount of contamination by ship and general transients, and
had larger fluctuation in wave height at large distances from the
hydrophone.

Data on wave height 4,5 were supplied by the Fleet Numerical
Weather Facility, U. S. Naval Postgraduate School, Monterey,
California, in the form of contour charts of wave height in 3-foot
intervals for the general areas of interest (fig. 3).

: Oi O
SOE CS
| Se
Figure 3. Portion of wind-wave analysis for 0600 GMT 01 October 1964 from Fleet

Numerical Weather Facility, Monterey, California, showing wave-height contours.

Contour interval is 3 feet.

One problem encountered in treating the noise data was
contamination by ship and traffic noise. Traffic noise, the contri-
bution of distant ships, is frequently not recognizable in the noise
records. Ship noise, however, displays a pronounced transient
effect on a continuous display in both broadband records and third-
octave-band records, particularly in the 50-to-63-c/s region.

For times during which there were obvious transient effects in the
broadband records, all noise data were deleted from the data from
station C, which were heavily contaminated. Figure 4 shows some
of the characteristic transients of these broadband records. In
this example, all of record C and all the third-octave-band data
corresponding to the times designated by arrows on records A and
B were deleted.

The method of recording sea-state conditions was to take
the hydrophone location as the center for the generation of a series
of ranges at equal radial increments as depicted:

WAVE-HEIGHT CONTOURS
SHORE

MAX WAVE HEIGHT, FT 2 3 5 9

HY DROPHONE

400 N. M. RANGE

In most instances, the storm configurations were such that it was
convenient and practical, as a first approximation, to use linear
interpolation. Data were recorded according to wave height in the
immediate vicinity of the hydrophone and the maximum values of
wave height observed anywhere on ares at radial ranges of 200,
400, 600, and 800 nautical miles from the hydrophone.

These data were compared with ambient-noise levels re-
corded at the center of the system, which were reduced by the
third-octave digital analyzer °’ to third-octave-band data starting
at 10 c/s and ending at 400-c/s midband frequency. Coefficients
of correlation between the third-octave-band noise levels and the

RANGE, N. M. 200 | 400 | 600 | 800

8

eens

= —=€=6 HOURS

TeVAe AL SMI

TIME

————

noise levels.

Figure 4. Typical sections of records of broadband ambient

10

cumulative wave heights” at increasing areas surrounding the
hydrophone, were computed. General trends in dependence of
noise levels for particular frequencies on varying areas of storm
magnitude may be detected in this way.

One of the salient problems associated with the study is the
possible overlap of the effect of storm activity at the various
ranges. For this reason, an effort was made to study the effect
of distant changes in wave height corresponding to times when
wave height nearby was relatively constant and small. The most
frequently occurring waves above the hydrophone were less than
3 feet, and one grouping was designed to observe only the times
for which the area had this sea state. Subsequent examination
showed that the most frequently occurring sea state at 200 nautical
miles was 3 feet. A second sort, made to include only times for
which the sea state was constant over the hydrophone (less than
3 feet) and at the 200-nautical-mile range (3 feet), enabled better
judgment from the correlation coefficients of the effect of distant
wave fluctuation on ambient-noise level.

A property of the maximum wave heights recorded from the
contour charts further compounded the aforementioned problems.
The validity of the correlation tests is subject to further question
as a few of the wave-height distributions were not normal. Note
in figure 5 the extremely skewed curves for the wave heights at the
source and at the 200-nautical-mile range. With further increases
in distance from the shoreline the distributions begin to take on a
more normal form.

The correlation between ambient sea noise in the low-
frequency range and local storm activity was further explored
with data from an automatic weather buoy associated with CNO
Project DS/200. The data were compared with third-octave-band
ambient-noise data at station D by means of the correlation coef-
ficient and by grouping the noise data to correspond to sets of wind
data that fell within certain Beaufort groupings.

Simple sums — the value at the source plus the maximum
value at 200 nautical miles, the preceding plus the maximum
value at 400 nautical miles, and so on.

11

12

OBSERVATIONS

200

ABOVE HYDROPHONE
----—- 200N.M. RADIUS
ees 400 INEM aRADIIWS
BSE TCOOINEMaRADIUS
ee) COONS MEIRADIUS

15-17 18-20 21-23
MAX WAVE HEIGHT, FT

Figure 5. Distribution of maximum wave heights.

(Bia

24-26

RESULTS

The effect of ever-increasing areas (approximated by the
cumulative wave-height tabulations) over which maximum wave
height is considered on the ambient-noise level in the third-
octave-band channels at each station is shown in figure 6. With
the exception of station C, all stations yielded coefficients of
correlation® which suggest a noise/wave dependence at frequencies
less than about 32 c/s and greater than about 160 c/s.

An apparent anomaly in the neighborhood of 20 c/s is noted
in figure 6. A possible explanation for it is the way the respective
seasonal characteristics of sound pressure level in these frequen-
cies vary with the seasonal wave-height characteristics. Note in
figure 7 that all stations exhibit a significant increase in sound
pressure level in the 20-c/s band for the months of September and
October. The increase probably results from 20-c/s signals pre-
viously reported by Cummings and Thompson®. In the areas
around station D, for example, the average local wave height de-
creases during these months, and thus a negative coeffienct
appears that is unusually large compared to the surrounding fre-
quencies. The seasonal effect of the predominance of the 20-c/s
signal is illustrated in figure 8. No peculiar effect appears at
these frequencies at the time of minimum occurrence of the
20-c/s signals (May and June).

Comparable results are yielded for all four stations by the
following data sets:

1. Occurrences for which the value of wave height above
the source was less than 3 feet, and

2. Occurrences for which the value of wave height above
the source was less than 3 feet and the value at the 200-nautical-
mile range was 3 feet. Station A (fig. 9) is typical. The smallest
number of points in any of the computations for data set 1 was 149;
for dataset 2,107. The first group showsa general decrease for the
coefficients compared to the parent sample (fig. 6) for nearly all
frequencies with the smallest decrease in the 16-to-25-c/s region.

*
Greatest 1 percent minimum critical value for the four

stations is 0.13.

13

14

COEFFICIENT OF CORRELATION

Beka
NVA

ABOVE HY DROPHONE
2E0S352 200 N. M. RADIUS
—-— 400N.M. RADIUS
—-—-- 600 N. M. RADIUS
—-—— 800N. M. RADIUS

0.3

ORS Cee

SO eat
, Dna tae STATION | |

“10 12 16 20 25 32 40 50 63 80 100 126 160 200 250 320 400
FREQUENCY, C/S

0.0

Figure 6. Variation with frequency of coefficient of correlation between sound
pressure spectrum level and cumulative maximum wave heights observed at
the indicated radial distances for the hours 0600 and 1800 GMT, April through
December 1964.

COEFFICIENT OF CORRELATION

ABOVE HY ote
20 . RAD

TRIG eae
fi, 5 en SI

Cena hee

a a

CRE. ea Res ea ees
EES Eoce a ialan ea ists oe eg ie eae oil
IO a as ores

-0.5
10 12 16 20 25 32 40 50 63 80 100 126 160 200 250 320 400

FREQUENCY, C/S

Figure 6. (Continued).

15

STATION

vie
CN Vs

(pave c000'0 4d dd

GN

Ne)
SOT NON NO SO)

14 ‘LHOISH JAVM XVW

‘TAAR1 WNYLIAdS JUYNSSAYd GNNOS

MONTH

Figure 7. Monthly average sound pressure level at 20—c/s midband frequency,

and monthly average local wave height.

16

COEFFICIENT OF CORRELATION

ABOVE HYDROPHONE

SOG0500 200 N. M. RADIUS
—-— 400N. M. RADIUS
=i = O00)NSM RADIUS
——-- 800N.M. RADIUS

ey)
Ws
yas
MET nei
Aes)

PERIOD OF LOWEST FREQUENCY
OF OCCURRENCE OF 20-C/S SIGNAL

, S Ay
NE 5 iY Cle
See a) 4 aa

PERIOD OF HIGHEST FREQUENCY
OF OCCURRENCE OF 20-C/S SIGNAL

. Sper N=91 bes
NAPE RN TT

a
Es
fe
i
‘
LEE LEELE
fey
4g
o]

JUS SEN Ser EN
LSC Seas

S
oll
10 12 16 20 25 32 40 50 63 80 100 126 160 200 250 320 400
FREQUENCY, C/S

Figure 8. Variation with frequency of coefficient of correlation between sound
pressure spectrum level and cumulative maximum wave heights observed at
the indicated radial distances.

18

COEFFICIENT OF CORRELATION

++ PERIOD OF HIGHEST FREQUENCY ee Be
; ale OF SCEURENGE OF 20 4606 SIGNAL Pan
| PERSIST eer
AES Ta S220
es | ll

ABOVE HYDROPHONE

ie PERIOD OF HIGHEST FREQUENCY a.

OF OCCURRENCE OF 20-C/S SIGNAL

PERIOD OF LOWEST FREQUENCY
OF OCCURRENCE OF 20-C/S SIGNAL
MINIMUM N = 91

-0.2 :
10 12 16 20 25 32 40 50 63 80 100 126 160 200 250 320 400

FREQUENCY, C/S

Figure 8. (Continued).

COEFFICIENT OF CORRELATION

DSSS 200 N. M. RADIUS
—w— 400N. M. RADIUS
—-—- 600N.M. RADIUS
—-——-— 800N. M. RADIUS

10 12 16 20 25 32 40 50 63 80 100 126 160 200 250 320 400
FREQUENCY, C/S

Figure 9. Variation with frequency of coefficient of correlation between sound
pressure spectrum level and maximum wave heights observed at the indicated
radial distances for periods during which wave height at source was less than 3

feet, April through December 1964.

19

20

At the 1-percent level, the critical absolute value of the correla-
tion coefficient is about 0.21. The second group suggests that all
frequencies with the exception of 20 c/s are unaffected by fluctua-
tion in sea height at ranges greater than 200 nautical miles (1-
percent absolute critical value for the second group is 0. 25).
Again, the suggested relationship in this narrow frequency group-
ing is probably merely a coincidental result from the pre-
sence of 20-c/s signals, and not the result of distant storm
activity.

Although the near-wind effect on noise has been described
in the literature, it was desired to use the data from the Navy
weather buoy for comparison with ambient-noise levels, and to
perform the same correlation computations on the same frequency
range as with the wave-height comparisons. There were several
advantages in using the buoy data — consistency of location of the
anemometer in relation to the surface and station, and accurate
wind-speed measurement. The wind data were compared with
noise data received from station D. The weather buoy was located
about 50 miles from the hydrophone location. The results (fig. 10)
show a high noise/wind correlation in the higher frequencies
(above 160 c/s) and no correlation for 10 to 16 c/s and 32 to 80
c/s . Minimum critical value at the 1-percent level for the 150
points is about 0.208. Although the number of data points was
limited, a sufficient number of points existed to group the data
into categories of Beaufort 2 (4 to 6 knots), Beaufort 3 (7 to 10
knots), and Beaufort 4 (11 to 16 knots)® (fig. 11). Standard tests
(¢ statistic) on significance of mean-value differences for the
Beaufort groupings were run for select frequency bands. Differ-
ences in mean levels for the Beaufort groupings for frequencies of
200 c/s or greater were significant at a 1-percent level. In the
20-to-25-c/s region only a few pairs (sound pressure level at 20
c/s for Beaufort 3 compared with Beaufort 2, for example) were
significant (5-percent level).

COEFFICIENT OF CORRELATION

0.7

0.6

0.5

0.4

0.3

0.2

0.0

-0.1

WW WZ ie 20 25 SP 40 50 63 BO 100 125 150 Ao Aso eyo Zoo

FREQUENCY, C/S

Figure 10. Variation with frequency of coefficient of correlation between sound
pressure spectrum level and wind speed measured at Navy weather buoy.

21

St ON
KER
faqe aaa
OOO
LL Le LL
S5)5)5)
I<
LO Lu Lu
ann
i |
J

|
1]

GResA

zW9/SNAQ 2000°0 3a dd ‘13A31
WN&LoAds AYNSSAdd GNNOS

16 20 25 32 40 50 63 80 100 126 160 200 250 320 400

12

10

FREQUENCY, C/S

Ambient noise versus frequency at station D, June through August 1965.

Figure 11.

22

CONCLUSIONS

Many of the forms of weather data now available (the data
from Fleet Numerical Weather Facility are considered the best
in the sense of the overall patterns they describe) do not lend
themselves well to this type of study. To use a high coefficient
of correlation in a derivation of a regression line prediction
model, one must be assured that the accuracy of measurement of
the independent variable is significantly greater than that of the
dependent variable (ambient noise). Such was not the case with
data used in this study. However, even though precise prediction
relations cannot be formulated, an indication is provided of the
frequency regions in which the noise is affected by wind and wave
height at deep-mounted hydrophones in open-ocean locations.

The results do not support the hypothesis of very-long-range
noise/storm dependence. They do suggest that both wind speed
and local wave activity have a significant effect on underwater
ambient noise greater than about 160 c/s, and that local wave
activity may have a small effect on low-frequency noise. By using
a 30-hour prediction chart, available at Fleet Numerical Weather
Facility, one may be able to predict whether the noise will in-
crease or decrease in regions greater than 160 c/s and to provide
a gross estimate of the amount of change. The general dip in the
correlation coefficient to insignificant values in the midfrequency
range (32 to 160 c/s) for most of the stations is probably due to
masking by ship and traffic noise.

23

24

REFERENCES

1. National Defense Research Committee. Division 6 Report 6.1-
NDRC-1848, Survey of Underwater Sound: Report No. 3; Ambient
Noise, by V. O. Knudsen and others, 26 September 1944 (PB 31021)

2. Wenz, G. M., "Acoustic Ambient Noise in the Ocean: Spectra
and Sources,'"' Acoustical Society of America. Journal, v. 34,
p. 1936-1956. December 1962

3. Navy Electronics Laboratory Technical Memorandum 840,
Effect of Winds on the Underwater Low Frequency Ambient Noise
Recorded at a Location Off the West Coast of the United States,
by W. L. Frisch and T. 5. Scanlan, 8 September 1965"

4, Fleet Numerical Weather Facility, Monterey, California,
Operational Forecasts of Sea and Swell, by W. E. Hubert, (1964)

5. Fleet Numerical Weather Facility, Monterey, California,
Numerical Environmental Prediction Progress Report, May 1964

6. Navy Electronics Laboratory Report 938, Third-Octave Digital
Analyzer (TODA), by J. V. Schaefer, 16 December 1959

7. Navy Electronics Laboratory Report 1286, Modification of
Third-Octave Digital Analyzer (TODA), by R. E. Cruse,
10 May 1965

8. Cummings, W. C. and Thompson, P. O., ''20-Hz Signals in
the Northeast Pacific," in Third U. S. Navy Symposium on
Military Oceanography, CONFIDENTIAL, 1966 (In press)

9. Von Arx, W. S., An Introduction to Physical Oceanography,
p. 68, Addison - Wesley Publishing Company, Incorporated, 1962

NEL technical memoranda are informal documents intended
primarily for use within the Laboratory.

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1. ORIGINATING ACTIVITY (Corporate author) 24. REPORT SECURITY CLASSIFICATION

Navy Electronics Laboratory, UNCLASSIFIED
San Diego, California 92152 2 RIGROUr

#3. REPORT TITLE

SEA NOISE VS NEAR AND DISTANT WAVE HEIGHT AND WIND SPEED

4. DESCRIPTIVE NOTES (Type of report and inclusive dates)

Research and Development Report, July 1965 to June 1966

5. AUTHOR(S) (Last name, first name, initial)

Masel, Wo Ibo

6. REPORT DATE 7a. TOTAL NO. OF PAGES 7b. NO. OF REFS
11 July 1966 24 9

8a. CONTRACT OR GRANT NO. 94. ORIGINATOR'S REPORT NUMBER(S)

b. prosectno. SF 101 03 15 1390
Task 8119

(NEL Ly 046 il ) 9b. STERNER ORT NO(S) (Any other numbers that may be assigned

10. AVAILABILITY/LIMITATION NOTICES

Distribution of this document is unlimited

11. SUPPLEMENTARY NOTES 12. SPONSORING MILITARY ACTIVITY
Naval Ship Systems Command
Department of the Navy

13. ABSTRACT

Correlation of measurements made in deep, open-ocean areas of the
Northeast Pacific indicates:

1. Sound pressure spectrum level is influenced by wave height and wind
speed at both ends of the frequency range considered (10 to 400 c/s); influence
is greatest between 160 and 400 c/s.

2, Ambient-noise levels between 32 and 160 c/s are the least influenced by
near and distant wave height.

3. For periods during which local wave heights were moderate and uniform,
no dependence of ambient-noise level on distant wave-height fluctuation was
observed.

DD .°98. 1473 101-807-6800 UNCLASSIFIED

Security Classification

SUNG TAGSIEIED heen

Security Classification

KEY WORDS

Ocean Waves - Acoustic Properties

Underwater Noise - Analysis

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project code name, geographic location, may be used as key
words but will be followed by an indication of technical con-
text. The assignment of links, rales, and weights is optional.

UNCLASSIFIED

Security Classification

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CHIEF OF NAVAL MATERIAL
MAT 0331
COMMANDER, NAVAL SHIP SYSTEMS COMMAND
SHIPS 2021 (2)
SHIPS 1610
SHIPS 1620
SHIPS 1631
SHIPS 204113
COMMANDER, NAVAL AIR SYSTEMS COMMAND
AIR 9132
AIR 9132 (DLI-304)
AIR 0322
AIR 03C
AIR (FASS)
COMMANDER, NAVAL ORDNANCE SYSTEMS COMMAND
ORD 604
ORD 604 (DLI-304)
ORD 533
ORD 5330
ORD 5330 (RUDC-2)
ORD 5330 (RUDC-3)
ORD (FASS)
COMMANDER, NAVAL FACILITIES ENGINEERING COMMAND
CODE 42310
CHIEF OF NAVAL PERSONNEL
PERS 118
CHIEF OF NAVAL OPERATIONS
op-312 F
OP-O7T
OP-701
oP-71
OP-724
OP-03EG
OP-0985
op-311
op-322C
OP-345
oOP-702C
oPp-713
oP 716
OP-922Y4C1
CHIEF OF NAVAL RESEARCH
CODE 416
CODE 418
CODE 427
CODE 455
CODE 461
CODE 466
CODE 468
CODE 493
COMMANDER IN CHIEF US PACIFIC FLEET
COMMANDER IN CHIEF US ATLANTIC FLEET
COMMANDER OPERATIONAL TEST AND
EVALUATION FORCE
DEPUTY COMMANDER OPERATIONAL TEST +
EVALUATION FORCE, PACIFIC
COMMANDER CRUISER-DESTROYER FORCE»
US ATLANTIC FLEET
US PACIFIC FLEET (CODE 425)
COMMANDER SUBMARINE FORCE
US PACIFIC FLEET
US ATLANTIC FLEE%
DEPUTY COMMANDER SUBMARINE FORCEs
US ATLANTIC FLEET
COMMANDER ANTISUBMARINE WARFARE FOR
US PACIFIC FLEET
COMMANDER FIRST FLEET
COMMANDER SECOND FLEET
COMMANDER TRAINING COMMAND
US PACIFIC FLEET
US ATLANTIC FLEET
OCEANOGRAPHIC SYSTEM PACIFIC
COMMANDER SUBMARINE DEVELOPMENT
GROUP TWO
COMMANDER SERVICE FORCE
US ATLANTIC FLEET
COMMANDER KEY WEST TEST +
EVALUATION DETACHMENT
DESTROYER DEVELOPMENT GROUP PACIFIC
FLEET AIR WINGS» ATLANTIC FLEET
SCIENTIFIC ADVISORY TEAM
US NAVAL AIR DEVELOPMENT CENTER
NADC LIBRARY
US NAVAL MISSILE CENTER
TECH. LIBRARY
PACIFIC MISSILE RANGE /CODE 3250/
US NAVAL AIR TEST CENTER
WEAPONS SYSTEMS TEST DIVISION
Us NAVAL ORDNANCE LABORATORY
LIBRARY
SYSTEMS ANALYSIS GROUP OF THE ASW
R-D PLANNING COUNCIL>
ASW SYSTEMS ANALYSIS STAFF /DU/
CODE RA
US NAVAL ORDNANCE TEST STATION
PASADENA ANNEX LIBRARY
CHINA LAKE
FLEET COMPUTER PROGRAMMING CENTER
ATLANTIC, TECHNICAL LIBRARY

INITIAL DISTRIBUTION

US NAVAL WEAPONS LABORATORY
KXL
LIBRARY
PEARL HARBOR NAVAL SHIPYARD
PORTSMOUTH NAVAL SHIPYARD
PUGET SOUND NAVAL SHIPYARD
SAN FRANCISCO NAVAL SHIPYARD
PHILADELPHIA NAVAL SHIPYARD
USN RADIOLOGICAL DEFENSE LABORATORY
DAVID TAYLOR MODEL BASIN
/LIBRARY/
US NAVY MINE DEFENSE LABORATORY
US NAVAL TRAINING DEVICE CENTER
HUMAN FACTORS LABORATORY
CODE 365H» ASW DIVISION
USN UNDERWATER SOUND LABORATORY
LIBRARY
CODE 905
CODE 920
ATLANTIC FLEET ASW TACTICAL SCHOOL
USN MARINE ENGINEERING LABORATORY
US NAVAL CIVIL ENGINEERING LAB.
L54
US NAVAL RESEARCH LABORATORY
CODE 2027
CODE 5440
US NAVAL ORDNANCE LABORATORY
CORONA
NAVY UNDERWATER WPNS RSCH & ENG STATION
BEACH JUMPER UNIT TWO
US FLEET ASW SCHOOL
US FLEET SONAR SCHOOL
USN MEDICAL FIELD RESEARCH LAB
USN UNDERWATER ORDNANCE STATION
OFFICE OF NAVAL RESEARCH
PASADENA
US NAVAL SUBMARINE BASE
NEW LONDON
US NAVAL SHIP MISSILE SYSTEMS
ENGINEERING STATION
US NAVAL AIR TECH TRAINING CTR 85
CHIEF OF NAVAL AIR TRAINING
USN PERSONNEL RESEARCH ACTIVITY
SAN DIEGO
USN WEATHER RESEARCH FACILITY
US NAVAL OCEANOGRAPHIC OFFICE
SUPERVISOR OF SHIPBUILDING US NAVY
GROTON
US NAVAL POSTGRADUATE SCHOOL
LIBRARY (CODE 0384)
DEPTe OF ENVIRONMENTAL SCIENCES
OFFICE OF NAVAL RESEARCH BR OFFICE
LONDON
BOSTON
CHICAGO
SAN FRANCISCO
FLEET NUMERICAL WEATHER FACILITY
US NAVAL APPLIED SCIENCE LABORATORY
CODE 92005 ELECTRONICS DIVISION
CODE 9832
US NAVAL ACADEMY
ASSISTANT SECRETARY OF THE NAVY R+D
US NAVAL SECURITY GROUP HDQTRS(G43)
ONR SCIENTIFIC LIAISON OFFICER
WOODS HOLE OCEANOGRAPHIC INSTITUTION
INSTITUTE OF NAVAL STUDIES
LIBRARY
AIR DEVELOPMENT SQUADRON ONE /VX-1/
CHARLESTON NAVAL SHIPYARD
SUBMARINE FLOTILLA ONE
DEFENSE DOCUMENTATION CENTER
DOD RESEARCH AND ENGINEERING
WEAPONS SYSTEMS EVALUATION GROUP
DEFENSE ATOMIC SUPPORT AGENCY
NATIONAL OCEANOGRAPHIC DATA CENTER
US COAST GUARD OCEANOGRAPHIC UNIT
COMMITTEE ON UNDERSEA WARFARE
US COAST GUARD HD@TRS(OSR-2)
ARCTIC RESEARCH LABORATORY
WOODS HOLE OCEANOGRAPHIC INSTITUTION
US COAST AND GEODETIC SURVEY
WASHINGTON SCIENCE CENTER - 23
FEDERAL COMMUNICATIONS COMMISSION
US WEATHER BUREAU
DIRECTOR» METEOROLOGICAL RESEARCH
LIBRARY
NATIONAL SEVERE STORMS LABORATORY
NORMAN» OKLAHOMA 73069,
NATIONAL BUREAU OF STANDARDS
BOULDER LABORATORIES
AUDIOLOGY-SPEECH PATHOLOGY CLINIC
FORT SNELLING
US GEOLOGICAL SURVEY LIBRARY
DENVER SECTION
US BUREAU OF COMMERCIAL FISHERIES
WASHINGTON» De Co 2024C
WOODS HOLEs MASSACHUSETTS 02543
HONOLULU» HAWAII 96812
STANFORD», CALIFORNIA 94305
TUNA RESOURCES LAB LA JOLLA

(20)

ABERDEEN PROVING GROUND» MDs
US ARMY R-D ACTIVITY
ELECTRONIC WARFARE DIVISION
REDSTONE SCIENTIFIC INFORMATION
CENTER
US ARMY ELECTRONICS R-D LABORATORY
AMSEL-RD-MAT
XL-C
FRANKFORD ARSENAL
US ARMY RESEARCH OFFICE /DURHAM/
WHITE SANDS MISSILE RANGE
COASTAL ENGINEERING RESEARCH CENTER
CORPS OF ENGINEERS» US ARMY
52D USASASOC
FORT HUACHUCA,
HEADQUARTERS» US AIR FORCE
AFRSTA
AIR UNIVERSITY LIBRARY
STRATEGIC AIR COMMAND
AIR FORCE EASTERN TEST RANGE
/AFMTC TECH LIBRARY - MU-135/
AIR PROVING GROUND CENTER» PGBPS-12
HQ AIR WEATHER SERVICE
WRIGHT-PATTERSON AF BASE
SYSTEMS ENGINEERING GROUP
USAF SECURITY SERV'CE
ESD/ESG
ELECTRONICS SYSTEMS DIVISION/ESTI/
Le Ge HANSCOM FIELD
UNIVERSITY OF MICHIGAN
OFFICE OF RESEARCH ADMINISTRATION
UNIVERSITY OF MIAMI
THE MARINE LABe LIBRARY
MICHIGAN STATE UNIVERSITY
COLUMBIA UNIVERSITY
HUDSON LABORATORIES
ELECTRONIC RESEARCH LABS
LAMONT GEOLOGICAL OBSERVATORY
DARTMOUTH COLLEGE
RADIOPHYSICS LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
JET PROPULSION LABORATORY
HARVARD COLLEGE OBSERVATORY
OREGON STATE UNIVERSITY
DEPARTMENT OF OCEANOGRAPHY
GEORGIA INSTITUTE OF TECHNOLOGY
CHIEF, ELECTRONICS DIVISION
UNIVERSITY OF WASHINGTON
DEPARTMENT OF OCEANOGRAPHY
FISHERIES-OCEANOGRAPHY LIBRARY
NEW YORK UNIVERSITY
DEPT OF METEOROLOGY + OCEANOGRAPHY
UNIVERSITY OF MICHIGAN
DIRECTOR» COOLEY ELECTRONICS LAB
ORe JOHN Ce AYERS
RADAR + OPTICS LABORATORY
TUFTS UNIVERSITY
UNIVERSITY OF WASHINGTON
DIRECTOR» APPLIED PHYSICS LABORATORY
OHIO STATE UNIVERSITY
ANTENNA LABORATORY
PROFESSOR Le Es BOLLINGER
UNIVERSITY OF ALASKA
GEOPHYSICAL INSTITUTE
UNIVERSITY OF RHODE ISLAND
NARRAGANSETT MARINE LABORATORY
YALE UNIVERSITY
BINGHAM OCEANOGRAPHIC LABORATORY
FLORIDA STATE UNIVERSITY
OCEANOGRAPHIC INSTITUTE
UNIVERSITY OF HAWAII
HAWAII INSTITUTE OF GEOPHYSICS «
ELECTRICAL ENGINEERING DEPT
HARVARD UNIVERSITY
GORDON MCKAY LIBRARY
A+M COLLEGE OF TEXAS
DEPARTMENT OF OCEANOGRAPHY
THE UNIVERSITY OF TEXAS
DEFENSE RESEARCH LABORATORY
ELECTRICAL ENGINEERING RESEARCH LAB
HARVARD UNIVERSITY
UNIVERSITY OF CALIFORNIA-SAN DIEGO
SCRIPPS INSTITUTION OF OCEANOGRAPHY
MARINE PHYSICAL LAB
PENNSYLVANIA STATE UNIVERSITY
ORDNANCE RESEARCH LABORATORY
NAVAL WARFARE RESEARCH CENTER
STANFORD RESEARCH INSTITUTE
MASSACHUSETTS INST OF TECHNOLOGY
ENGINEERING LIBRARY
MIT-LINCOLN LABORATORY
LIBRARY» A-082
RADIO PHYSICS DIVISION
THE JOHNS HOPKINS UNIVERSITY
APPLIED PHYSICS LABORATORY
INSTITUTE FOR DEFENSE ANALYSES
FLORIDA ATLANTIC UNIVERSITY

21005

(RTD)