SF.

personnel,

2=5

ONR-H.O, obtained its estin:te of shot time underwater temperatures

on the basis of bathythermocraph (bt) reciiags from the DD-593 at H+15, H=5,
and H=] minutes and preeshot bt data taken fror three points in the array
starting on D-7 day.
Air Overpressure.

The ICL installed three near surface gages on vessels in

the array and two balloons, each supporting self-recording gages at heishts
of 500!

and 1000'.

Records were obtrined from two gages from the balloon

station at 3413' and two surface gezes it. <346' range.

Records showed two

distinct pulses; it. is believed the first .uise results from underweter shock
transmitted across the watereair iunterfice anc the second from bubble effects.

Maximum pressure recorded was 0,21 psi at 70! slevation, 2346' range.

Péak

pressures showed general agreement with predictions based on HE results, ~

Surface Phenomena.

The Scripps Institute «f Oceanography (SIO) measured water

waves and NOL studied all other surface oh nomena i.e. spray domes, plumes,
base surpe, etc.

Photocraphy from 4 fsircr..ft

was the principal means of dita collertion.
graphic coverage was excellent.

id several surface stations
‘‘ith the clear weather, photo-

Film anal-sis in progress ct this writing is

expected to provide thorough document-ticy cf she phenomena of interest,
Surface phenomena bore a marked rerem!Lanc: to "llewam.

‘later waves containing

approximately 4 of the weapon onerczr wore observed,
Hydrodynamic Yield,

The Armour -cseare> Founcatior (..2F) failed in their

attempt to measure the close-in propa atior of the shoc:: front.
used by Armour was the previour ly successfil igwam nethod.
stable platform was the principel

The technique

The lack of a

cour of “silure.

Shallow Lezoon Shot = Umbrella,
ealQ0e
co

Underwater Pressures.

BG

teen stations.

NCL successfully easured underwater pressures at six-

Records obtained at disterces of 500 to 8000 feet from sur~

S.

face zero, at depths from 10 feet down to 13C fect, covered the pressure range
;

Copir n

.

f bay:po°vt

os

Wen

os

PiGe.

“«

77

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