JC1/L14-2(371020)
                            -2-                             
Again, the military value of lighter-than-air
craft of all kinds depends upon the situation of the nation
wishing to use them. Lighter-than-air craft have little
offensive value. In the opinion of this Department their
operation under European conditions, In close proximity to
anti-aircraft artillery and within easy range of high 
performance shore based aircraft, would be fraught with risks
that would outweigh the possible advantages that might be
gained.
 
 
In note direct response to the questions raised
in the third paragraph of your letter:
 
 
First- It ts hardly possible that 10,000,000
cu. ft. of helium could be used for military
purposes in Europe. If it were no used, the
resulting performance of lighter-than-air
craft would not be an effective as that
obtainable with hydrogen, and since this
quantity of helium would be rapidly dissipated,
it is not probable that helium
would be used in any European military
operations.
 
 
Second - if helium were used for mllitary 
purposes, it is doubtful that it would result 
in saving the value of any lighter-than-air 
apparatus. Helium in not known to have saved 
the cost of any lighter-than-air apparatus as 
distinguished from saying the lives of people 
carried.
 
 
Third- it is difficult to appraise the value 
of miltary obseration balloons containing 
10,000,000 cu. ft. of helium because no nation 
has seen fit to employ helium in observation balloons, 
largely because of the difficulties and expense of 
delivering helium to the balloons and because so doing 
would reduce the performance of observation balloons to 
a point below that obtainable with hydrogen. The value 
of military balloons, regardless of what is used to inflate 
them, is a moot question on which the Navy Department is 
not the best authority. So far as naval operations are 
concerned, observation balloons are entirely obsolete. 
The use of helium in barrage type balloons, such an are 
reported as being con-