Engines of Our Ingenuity
No. 1364: RADAR

by John H. Lienhard

Click here for audio of Episode 1364.

Today, devastation follows when we don't trust a new technology. The University of Houston's College of Engineering presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

Radar is almost as old in concept as radio itself. Radio pioneers Marconi and Tesla both saw that we could locate metal objects by bouncing radio signals off them. As early as 1904 a German engineer named Hülsmeyer patented a radio echo device meant to locate ships at sea.

During the 1930s, all the major powers worked to develop usable airplane and ship spotting systems using radio waves. In 1942 the U.S. Navy began using the acronym RADAR, which stands for RAdio Detection And Ranging.

As early as 1936, American army and navy engineers discovered they could detect aircraft at distances of more than a hundred miles when they used long enough radio wavelengths. The army had mobile detection units in production by 1940. They field-tested the first of these units in Panama. By late 1941 five units were being field-tested in Hawaii.

One of those Hawaiian units was placed on the northern tip of Oahu. Through the night of December 6, 1941, Private Joseph Lockard was training Private George Elliott in its use. They were to go off duty at 7:00 AM, but the truck that was to pick them up and take them to breakfast was late. So Lockard gave Elliot some extra time on the unit. At 7:02, Elliott saw a very large reflection, 136 miles due north of their position.

They tracked the signal for eighteen minutes; then Elliott called the private on duty at the Information Center, his lieutenant dismissed the report -- said it was nothing to get excited about. When the lieutenant finally got on the phone, he told Lockard not to worry about it. Lockard and Elliott kept tracking the signal until 7:39 AM, when the 183 Japanese dive bombers and fighters that were generating the signal were only twenty miles away. Then the truck came to take them to breakfast. They folded up their equipment and left. Sixteen minutes later, the planes hit Pearl Harbor.

In the next moments we lost three thousand people, dozens of large ships, and eighty percent of the airplanes on Oahu. Still, it's too easy to criticize shortsightedness. Radar was a new invention, and if invention weren't alien, it wouldn't be invention. We have to be introduced to new technology -- gradually brought to understand what it can do. Inventions have to be championed, even when they appear just at the right moment.

The great revolutionary inventions have seldom been recognized in their first incarnations. Light bulbs, steamboats, and telegraphs had all been invented and put to use long before Edison, Fulton and Morse came on the scene to show us their full potential.

And so we saw the Japanese airplanes coming and didn't believe our eyes. Pearl Harbor had to go up in flames before we could learn to take radar seriously.

I'm John Lienhard, at the University of Houston, where we're interested in the way inventive minds work.

(Theme music)


Wohlstetter, R., Pearl Harbor: Warning and Decision. Stanford, CA: Stanford University Press, 1962.

Worth, R. H., Jr., Pearl Harbor. Jefferson, NC: McFarland & Company, Inc., Pubs., 1943, Section Three, Radar: The Great Missed Opportunity.

For more on Pearl Harbor, including the un-role of the radar unit on northern Oahu, see:
http://www.execpc.com/~dschaaf/mainmenu.html

I am very grateful to listener George McDonald for sending me an account by his father, who received Lockard's phone call on the morning of December 7, 1941. To read that remarkable account, Click Here. In 2005, the Army finally commended Joseph McDonald posthumusly. The commendation was presented to George McDonald by Senator Chris Dodd and Brig. General Thad Martin.

This is a considerably revised version of Episode 42.



The Engines of Our Ingenuity is Copyright © 1988-1998 by John H. Lienhard.

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