Attachment 1

    Office of Information Services Air Force Special Weapons
      Center, Air Research and Development Command Kirtland
                 Air Force Base, New Mexico re:
                Early Cloud Penetration, 1/27/56

ISO 56-23                                         27 January 1956

              Air Research and Development Command
               Kirtland Air Force Base New Mexico

Exclusive to Hq, ARDC


    AFSWC, Albuquerque, N. Mex. (27 Jan) -- In the event of
nuclear warfare the AF is confronted with two special problems.
First is the hazard to flight crews who may be forced to fly
through an atomic cloud.  Second is the hazard to ground crews
who maintain the aircraft after it has flown through the cloud.

    What are the dangers to be encountered by the personnel who
fly through the cloud?--How much radiation can they stand?--How
much heat can the aircraft take? -- Can the ground crews
immediately service the aircraft for another flight?--If so, what
precautions are necessary to insure their safety?  The answers to
these problems are part of a continuing research program
conducted by the AFSWC.

    The program was originally started during the 1951 Nevada
Proving Group atomic tests called Operation Greenhouse.  At that
time rats and mice were placed aboard B-17 drone aircraft which
were then flown through the cloud.  Upon return of the plan to
its base the occupants were removed and subjected to test to
determine the amount of radiation they had absorbed.

    In the 1953 Upshot-Knothole tests, monkeys were used so that
experiments could be conducted on larger animals nearer the size
of man.  QF-80 drone aircraft were used to these experiments,
their speed more nearly approximating that of current operational

    As a result of all these studies and experiments the
scientists behind the scenes felt their knowledge of the
radiation hazards had progressed to a point where they were sure
manned aircraft could safely fly through a


ISO 56-23


radioactive cloud.

    They proceeded cautiously at first, and the first manned
aircraft to fly through a cloud penetrated the radioactive mass
45 minutes after bomb burst.  The aircraft itself was filled with
equipment to measure the amount of radioactivity inside and
outside the plane, the temperature of the gasses inside the
cloud, and other data needed by the scientists to make
calculations and compare actual results with their earlier

    The occupants of the plane were also rigged with various
devices for registering the amount of radioactivity received by
them.  Some wore various types of protective clothing, others
film badges designed to register varying degrees of radioactive
intensity, and still others swallowed pills of wax-coated film
attached to strings to show the amounts of radioactivity absorbed
internally.  The strings were used to suspend the pills in the
center of the scientists' stomachs and to retrieve the pills for
later study.

    Findings were then analyzed and compared with predicted
results and were determined to be essentially the same.

    After these early experiments, cloud penetrations were then
made progressively earlier after the bomb burst until it is now
known that the radioactive cloud can be entered as early as five
minutes after detonation.

    Ability to penetrate a radioactive cloud as soon as possible
is of great importance due to many factors.

    From the defensive point of view it is imperative that we
know how soon our fighters can fly through a cloud in pursuant to
energy bombers if the latter succeed in penetrating our outer
defenses to bomb their assigned target in this country.  Also,
should two or three enemy bombers get through our defensive
network, the second and third, or succeeding bombers may fly
through the cloud resulting from the bomb burst of the first, and
by knowing how soon our fighters can enter, the ADC can then plan
on intercept procedures to try and prevent the remaining bombers
from reaching their targets.

    At the same time these experiments to determine how soon our
aircraft could safely enter a radioactive cloud were being
conducted, other and equally important tests were being made to
determine how soon these same aircraft could be reserviced and
made ready to fly again.

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    After the aircraft had completed their cloud penetration
runs, they returned to base where the ground crews took over.
Here they were carefully gone over with radiation detecting
devices to determine how much radioactivity remained on the

    First, we wanted to know how soon our ground crews could go
to work on the plane, making any necessary repairs, performing
preventive maintenance, and refueling.  In time of war these
functions become extremely important, since every available
aircraft must be kept in a state of operational readiness the
maximum possible time.

    At first, the planes were thoroughly washed down with
decontamination devices in an attempt to rid them of all
radiation possible.  They were then again subjected to a thorough
examination with radiation detecting devices to determine how
much radiation had been washed away.

    The results of these experiments were notable in many ways.
It was determined the "washing down" or decontamination process
was unnecessary, because the main sources of the collected
radiation were in cracks, crevices, around rivets, and in pitted
areas of the aircraft's "skin".

    Since the decontamination process failed to rid these areas
of radiation anyway, little was gained by washing off the
contamination on the smoother surfaces.  It was also discovered
that there was no radiation danger to the ground crews providing
they wore gloves to insure their skin did not come in direct
contact with the contaminated areas.

    These findings, along with the findings of the hazards, or
lack of hazards, encountered in flight through a radioactive
cloud, have led to some startling changes in the Air Force's
methods of dealing with these situations, which only a few short
years ago posed a major problem.

    From an economy standpoint they have saved the taxpayer
thousands upon thousands of dollars.  They have been in
inestimable value of the planners charged with the responsibility
of protecting our country against a possible air attach by an
aggressor nation.  An finally, they have been of great aid in
boosting the moral of our Air Force to an all-time high because
the man exposed to these hitherto unknown dangers know they
aren't being sent out on a suicide mission and they know exactly
what to expect and how to prevent exposing themselves to any
unnecessary dangers.

ISO 56-23


    The savings in dollars and cents is accomplished in many
ways.  Contrary to popular belief in the beginning, there is no
need for flight or ground crews to be specially equipped with
protective clothing.  Thus, this knowledge alone will save many
thousands of dollars in research and experimental work which
otherwise would be necessary to develop filters and other air
purification devices, which at first was thought to be absolutely
necessary.  A fringe benefit of this same development is the
release of many scientists and other research personnel, who
would have been occupied on these projects, to work on other
important developments.

    More dollars will be saved since an aircraft can be
reserviced immediately upon landing and returned to action in a
matter of minutes, thereby cutting down on the number of standby
aircraft needed if a plane had to be grounded for a day or so
after a mission.

    In addition to the savings due to the elimination of
research and development of special clothing and equipment,
tremendous savings will also be realized now that the manufacture
of such items is known to be unnecessary.

    Many man hours will be saved, also resulting in savings of
money, since special crews won't have to be trained to handle the
decontamination process.  These men, instead, will be trained in
other fields, lessening the Air Force's vast overall manpower

    While their achievements failed to receive the widespread
acclaim accorded the flight crews who actually made the cloud
penetrations, the soldier-scientists of the Air Force Special
Weapons Center's Biophysics Division were the real heroes behind
the scenes.  Without their knowledge and painstaking research we
would still be in the dark ages concerning radiation and its
effects on the human body.