52 Dahlgren 



armored deck to the thick armor that would definitely break up a bomb if it did 

 not detonate by that time. There were a lot of ships, like cruisers, that wouldn't 

 have for their armor deck more than about a 2-inch thickness of steel, and there 

 were some ships that had even a little less than that. So we built a deck target. 

 Against this deck target, we were testing inert-loaded bombs that had the fuzes 

 that were supposed to select the action. The fuze, if it hit a light plate that the 

 bomb could penetrate, would not function, but if it hit a thick plate that was 

 capable of breaking up the bomb, the fuze was supposed to function before the 

 bomb broke up. It was called a selective-action fuze. We did an enormous 

 amount of testing of such during the development of the fuze for what they 

 called, I think, the general-purpose bomb, or light-case bomb. Our deck target 

 was about 1200 feet north of the Terminal Range Bombproof. We'd stand up 

 on top of the bombproof while the airplanes would come in and we took 

 pictures. We had a whole set of cameras, ranging from those that operated at 

 about 120 frames per second up to the I6mm, built by Eastman, that could go as 

 fast as 2000 frames per second. Now they have cameras that will take up to 

 16,000 or 18,000 frames per second. For winter tests, we had to keep the 

 cameras warm all night with electric lights so they'd be ready to go first thing in 

 the morning. If they got cold, the film would get brittle and break up in the 

 camera. 



I had the job of arranging the tests and planning the photographic coverage 

 and, in fact, handled most of the camera operation myself with remote-control 

 switches back on the bombproof. 



The bombs had small charges that produced smoke puffs which came out of 

 ports on the side, and we could tell when the fuze operated by when we first saw 

 the smoke and flame coming out of these ports. Then, with the cameras, we 

 could tell by the time delay how long it took for the bomb to detonate after it 

 struck the top deck. Sometimes it would go right on through and impact on the 

 second deck, and we would have to determine how much of the bomb crushed 

 or how long it was after impact on the second deck before the bomb functioned. 



This was most of the bombing stuff. Of course, when we got to armor- 

 piercing bombs, then, instead of dropping them, most of the development 

 work was done by shooting them out of a gun and into the armor plate because 

 they were so expensive. Of course, we did drop some armor-piercing bombs. 



After your work with bombs and bombsights, you moved into general ordnance and 

 ballistics in 1942. Can you describe the environment surrounding the range operation 

 during the war years and your later career, perhaps highlighting some of the significant 

 events? 



In 1942, the early part t)f the war, I was working in the Experimental 

 Department as an assistant in a group of assistants to the Experimental Officer. 



