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TIT Te ETE
Choater 2
PROCEDURE
2.1
OPERATIONS
‘
On each shot of the test series, jet aircraft departed from Eniwetok Atoll, New through
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the cloud, and returned to base. [It was on these aircraft that meus:rements were made.
During Shots Erie and Inca the F-84 aircraft used for sampling by the Test Aircraft Unit
were studied. During Shots Zuni, Flathead, Dakota, and Apache measurements were
mde un 5-57 aircraft assigned to Project 2.66 from Tactical Air Command. Thelatter
were flown through the cloud at somewhat earlier times than those employed by the
sampling aircraft.
Studies were made on aircraft which flew threugi the cloud at times varying from 41
to 81 minutes after detonation. The aircraft were on the ground within an hour after the
cloud penetration. Contamination etudies were begun immediately and extended for about
9hcurs.
Decay studies continued for an additional 12 hours.
Whenthe planes landed, a survey was made at predetermined spots using a TIB. The
areas were clearly marked and the average dose rate was used to calculate the exposure
time for the photographic filin.
Radteratepfraphs were made at intervals continuing up to 9 hours after time of detonation. These were intended to measure the amount and distribution of the contamination.
£dditioaal exposures were madein the evaluation of protective gloves.
2.1.1 Instrument Survey. The survey of the aircraft was made witha TIB.
These
aR be
readings were made ut a distance of % to A inch from the surface. In addition to the
surface survey, several decay studies were made for times up to 44 hours efter detonation. The T1B was used for these studies, and measurements were made at several
locations on the contaminated aircraft.
2.1.2 Radioautographic Techniques. As suon as -he surface dose rates on the aircraft
had been established by the TI1B survey, exposure of the photographic film was bezun.
The areas selected for the exposure were protected with a thin covering of polyvinylacetate
sheet plastic. This covering protected the contaminausn from rainfall and other physical
disturbance.
A film of appropriate speed was selected and placed over the chosen area. Masking
tape was used to hold the film in cloge contact with the surface. At least two exposures
were made on each area. Exposure times differed by a factor of two or three. This was
done in order to ensure that filins of readable density would be obtained. To reduce
darkening by the gammafield surrounding the aircraft to a minimum, the film was kept
at a distance of about 100 feet from the aircraft, both before and after the controlled
contact exposure. Since this could not eliminate gamma exposure entirely, control filma
were kept in a simiiar environment. The density of these control films was subtracted
fcom that of the exposed films.
The exposed film was developed with uniform agitation in Kodak ‘iquid X-ray developer
(4 quarts of developér, 4 gallons of water) for 5 minutes at 67.45 + 0.02 F, Immersed in
an acetic acid stop bath for 2 minutes, fixed for 7 minutes in Kodak liquid X-ray fixer,
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