added to the Hardw.-k schedule in June 1958. Because co. its nature and
possible tactical interest, three new Program 2 projects were created and
an existing one extended in order to document the nuclear effects. Three
projects of Program 34 (Projects 34.8, 34.9, and 34.10) were placed under
the technical direction of Program 2. These are discussed in Sec. 2.4.

Quince a -: a result, the Fig event was added

to the schedule and detonated on August 18, 1958.

The yield was SCTED

Project 1.4, Crater Measurements, measured the size of the crater

produced by the subkiloton detonation. There were no project personnel in
the EPG, as only a contractor survey was required. It was found that the

crater produced was elliptical in shape, with the long axis roughly corres-

ponding to that of the device. The diameters were 48 and 54 ft, respectively,
measured from lip to lip. The depth was 9.7 ft below grade with a 3.6-ft

lip above grade.

At the time of measurement, D + 3 days, there was evi-

dence of earth slides which resulted from severe rains that had occurred
since the detonation. The crater was briefly observed on D + 1 day, prior
to the slides. Based upon this observation and the measurements made a
day later, it is estimated that the original crater was 2 to 3 ft deeper and
4 to 6 ft smaller in diameter from lip to lip immediately following the detonation,
The objectives of Project 1.7, Overpressure Measurements, were to

document the overpressure measurements resulting from a

eto-

nation and verify or extend existing scaling laws. The instrumentation consisted of 36 standard PT and Q gages containing pressure capsules located
at ranges from 40 to 700 ft from ground zero. As the yield of the device
was uncertain, it was necessary to provide the above instrumentation to accomodate a wide range of pressures.
D

The Fig device produced a nuclear yield wae: measured by
radiochemistry. Twenty-eight of the 36 instruments provided good records.
Some failures were experienced due to undetermined causes at the close-in
ranges. It is felt that these could be the result of heavy ground shock and

motion, which in some instanc
sures recorded varied from

tter

Ss

cs.

hin points ot against curves scaled up from
of nuclear yield showed a reasonably close fit.

Pres-

.

There

was, however, a minor deviation in the slope of the recorded curve which

cannot be explained without further study of the records and investigation of

possible sources of experimental error due to the closeness of the instru-

ments to the detonation.

Preliminary field analysis of the data indicates

that, using existing scaling laws, pressures can be predicted for
detonations with reasonable accuracy.
Neutron flux measurements made by Project 2.4 were discussed in

some detail in the Program 2 portion of this report.

TED

During the field phase

of the operation, project participation was extended to include the Quince and
Fig events and had as its objective the documenting of the neutron flux and
spectra for the RE). Two neutron lines were established to obtain the desired data.’ One was in the direction of the extended long axis of
the device and ran out to a distance of 1039 yd, and the other was perpendic-

ular to the device's long axis and extended for a distance of 900 yd.

From

the data obtained it was learned that an asymmetric flux pattern was apparent,
being approximately 30 per cent higher along a line perpendicular to the long

axis of the device.

The maximum dose along the short axis was 132,000
38

AFWL/HO

37

Select target paragraph3