Next followed a series of agonizing months while the basic designs were refined, detailed, and reduced to practice in actual construction. Each day brought fresh heartbreaks which dwarfed those of the day before. Lesser men would have given up the task as impossible. But each problem surmounted gave encouragement and brought the final solution nearer to view. Steadily, persistently, progress was made. It is not intended to recount the many difficulties en countered, but simple justice demands a record of the achievements attained.</P>
Extraordinary security measures were taken during the design, manufacture, and test of “Little David,” Mr. Iversen carried out all preliminary design and layout work with the aid of one draftsman in a special locked room. The project as a whole was designated Bomb Testing Device Ti in order to conceal the actual nature of the weapon.</P>
As developed, the base of the 36-inch mortar was in the form of a steel box approximately eighteen feet long, eleven feet wide, and ten feet high. It was designed to be emplaced in a pit, using shell or bomb carters where convenient. The base was designed to contain elevating and traversing mechanisms and all control equipment, including a hydraulic pump and packs for use in emplacement and removal of the base and for mounting the tube assembly.</P>
The original specifications for the mortar tube provided for a yield strength of 65,000 pounds per square inch. By employing a novel method of triple quench, Mesta was able to raise the yield point to 95,000 p.s.i. which was reflected in a range in crease from the original 7,500 to 9,500 yards.</P>
This latter unit consisted of the rifled muzzle loading mortar tube of right-hand twist (one turn in sixty calibers), the elevating segment, and the recoil mechanism. Ammunition of various types was developed ranging from 3,000 to 3,650 pounds in weight and incorporating preëngraved rotating bands. The propellent charge consisted of a 136-pound base section and two zone increments each weighing forty-one pounds.</P>
On October 9, 1944, just five month’s from the day the contract was received, the pilot model was completely assembled. Following plants tests, the units were transported overland by road to the Aberdeen Proving Ground. By numerous trips over the highways, the roadworthiness of the materiel was effectively demonstrated. The base unit of the pilot mortar was shipped on October 28th, arriving at Aberdeen the following day, and within thirty minutes it was emplaced in the pit. The tube was shipped two days later and was likewise installed in half an hour.</P>
<>The first test projetile was fired from “Little David” on October 31st. preliminary projectile ballistic and design data had been obtained from firing special 155-mm. ammunition shaped like the mortar projectile and proportioned similarly as to weight. In order to accumulate range data for the firing tables, extensive and expensive firing would be required. Therefore, the 75-mm. Howitzer M8, which had about the same exterior ballistics and a high rate of fire, was used for determination of preliminary data and served to place the mortar accurately on the target.</P>
The destructive effects of “Little David” fully lived up to expectations. Immense, deep craters were formed which could fully accommodate a fair-sized apartment building. Its effect on the German type of redoubt was evaluated by static detonation which indicated complete crushing of the concrete slab over an area of some one hundred square feet. The concussion effect of adjacent detonations caused extensive damage so that a redoubt and personnel inside would have been permanently demobilized.</P>
In the meantime the war in Europe was progressing at an accelerated pace. General Patton in his armored drive cross France had destroyed the last German hope of a switch-line defense. The Siegfried Line had been breached at Aachen. The termination of hostilities in Europe only awaited the transport of needed materiel to the front and the arrival of good weather. The misguided German offensive of the Bulge in December merely served to deplete the enemy’s reserves and hasten the end. Accordingly, the help of “Little David” was not required in the European theater, and the project was reoriented toward Japan.</P>
On Okynawa, progress was proving slow and costly were the Nips were dug in along Shiri Ridge. This looked like an ugly portent of things to come when the final invasion of the Japanese mainland would begin. Again a weapon was needed that could blast out the foe from as deep as he could dig, and plans were made to ship the mighty mortar and trained personnel to assist in the coming attack. Then came a holocaust from the sky! The atomic bomb had settled the issue, and peace was won. Though never destined to fire a shot in battle, “Little David” remains an epic of American industrial might—the largest cannon in the world.</P> </P> </P>ps. 有谁可以帮忙翻译，谢谢</P>
楼主: BUSH
发表于 2004-8-10 11:56:09
>The first test projetile was fired from “Little David” on October 31st. preliminary projectile ballistic and design data had been obtained from firing special 155-mm. ammunition shaped like the mortar projectile and proportioned similarly as to weight. In order to accumulate range data for the firing tables, extensive and expensive firing would be required. Therefore, the 75-mm. Howitzer M8, which had about the same exterior ballistics and a high rate of fire, was used for determination of preliminary data and served to place the mortar accurately on the target.</P>