On the morning of January 6 twenty-one years ago a specially marked shell was loaded into the chamber of an anti-aircraft gun on board the cruiser Helena under attack at Guadal canal. Within the shell's nose was a new and top secret fuse containing a tiny radio that, bat-like, sent out a signal, listened for its echo bouncing off a target and then exploded the shell when it reached its point of closest approach. Inside it was a tube developed in Newton.

This debut of the proximity fuse was an unchallenged success and kept one man busy most of the time stenciling trophy silhouettes on the ship's smokestack.

Using the proximity fuse converted "near misses" to direct hits as the shells exploded before they whooshed past their targets.

Although it was still necessary to "lead" the target, just as a hunter leads a flying duck, the proximity fuse converted the Japanese planes into sitting ducks.

A year earlier, many scientists and ordnance experts working on the secret proximity fuse project were stumped by the lack of a special electron tube that could do the job.

Unaware of the fuse program, Dr. Percy L. Spencer of Raytheon Co. had adapted a hearing aid tube to control his young son's flying model airplane. The tube was filled with argon gas. The model airplane turned, climbed and dived on signal and the Spencer boys were the envy of their friends in Newton.

Word of the interesting tube reached the fuse makers and Raytheon was asked to develop a tube that could run the fist-sized, radio transmitter-receiver they were perfecting. It had to survive spins of 15,000 G and be rugged enough literally to be shot from guns.

Early experiments produced artistically bent and spent tubes. Eventually, a successful design was achieved by a group of Raytheon engineers working with Dr. Paul Weeks at Raytheon's Chapel St. plant in Newton. Later the tubes were produced at the rate of tens of thousands every day.

At D-Day in Normandy the proximity fuses were fired only by the Navy and only towards seaward to lessen the risk of the enemy capturing a dud.

Released to the Army at the Battle of the Bulge, the fuses helped turn the tide as they increased firepower by restraining attacking aircraft and ground forces. Against land targets the proximity fuse detonated at the most effective height above the ground rather than bursting upon impact.

Although improved since World War II, the fuse that changed tactics during World War II is still found throughout our Armed Forces and the tube at its heart is still in production here to meet a new contract from the Army. Deliveries are under way now on an order for a substantial quantity of the tubes.

As for the model airplane, Dr. Spencer's tube is the basis for all remote control systems in model airplanes today.

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