Evening star., 1945-09-21
Fuse With Radio Set Revealed
By Navy as RivoIing Atom Bomb
Chevy Chase Man
Directed Development
Of Eye for Shells

How the Navy developed a radio
proximity fuse" so accurate it ex-
plodes a shell within 10 feet of any
target and contributed signally to
American victory on both land and
sea has been revealed by Assistant
Secretary of the Navy H. Struve
Hensel.
At a press conference late yester-
day he ranked this highly secret de-
vice as second only to the atomic
bomb as the greatest scientific de-
velopment of the war. Mr.. Hensel
credited artillery shells fused with
the device as being responsible for
Irepelling japanese suicide plane at
tacks on American ships off Oki-
naWa, the repulSe of German forces
in the Battle of the Bulge and dras-
tically reducing the effectiveness of
the vi robot bomb attacks on Lon
don.
Development of the fuse, first
used against japanese planes by the
cruiser Helena on January 3, l943,
was carried out by a group of scien-
fists working under the direction of
Dr. Merle A. Tuve, 1875 Hesketh
street, Chevy Chase, Md, of the Ma
tional Defense Research Commit
tee. Research work, begun in 1910,
was executed with the cooperation
of the Carnegie Foundation and
Johns Hopkins University.
Five-tube Radio.
The deadly-accurate fuse was de-
scribed by the Navy as an extremely
rugged five-tube radio receiving and
sending set which occupies space
no larger than pint milk bottle.
At the heart of the device is a
vacuum tube which sends out elec-
tro- magnetic waves on impulses at
the speed of light-180,000 miles per
second. The impulses are reflected
back to the tube by any target that
gives a radio reflection, such as
metal objects, water or earth.
If a projectile SO fused passes
within 10 feet of any target, reflect
ed impulses act on the fuse circuit
to trigger a switch which detonates
the main explosive charge.
Invention of the fuse, the Navy
said, greatly simplifies the task OF
gunners behind the 5-inch guns
which are the principal long-range
antiaircraft weapon. Using the ear
lier time fuses, the gunner had to
estimate the time of flight between
the gun and target and set time
fuse. A slight error in fuse setting
caused the shell to explode inef-
fectively.
use of the VT (radio) fuse" the
Navy said, Excludes errors inherent
in time-fuse mechanisms and makes
possible maximum results at the
split-second speed demanded by
modern antiaircraft fire"
| AS examples of the fuses effec-
tiveness, the Navy said that at Oki-
nawa two destroyers, the Evans and
Hadley, which employed it, knocked
down 35 Japan planes in 80 minutes
During the Ardennes breakthrough
on the western front in December
1914, the first time radio-fused
shells were used on land, the War
Departments official observer re-
ported that "the terrific execution
inflicted and the CONSERVATION re-
sulting from night and day bom-
bardment contributed materially to
nalting the advance and fastening
the reduction of the salient"
Developed Secretly.
The invention was given to the
British for use against German VI
bombs. Its effectiveness is showr
by data covering the last four week:
of the 80-day attack. During tht
first week the British destroyed q
per cent of all vi targets, 46 pei
cent in the second week, 81 per CEN
in the third and 70 per cent in tht
fourth.
Development of the fuse, the Navy
said, was surrounded by the utmos
secrecy. Workers on production
lines did not know what they were
making. Although, at the end of ths
war, 81 firms using ITO different
factories were producing 10000
fuses daily, the enemy apparent!
never learned the reason for tn,
terrible accuracy of American artil
law ND