Word: pratt
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...Bootstraps. Designed to hurl more than a ton of instrument payloads all the way to the moon, the 28½-ft. Centaur generates 30,000 Ibs. of thrust with its two restartable Pratt & Whitney engines. The hydrogen fuel they burn has been the key-and the curse-of the Centaur system from the time it was born on engineers' drawing boards. As early as 1909, U.S. Rocket Pioneer Robert Goddard noted that hydrogen (in liquid form, known as LH.,) might prove to be the optimum chemical rocket fuel. Its light molecular weight, less than half that of standard liquid...
...when Pratt & Whitney engineers set out to develop the Centaur's engines, they boldly planned to turn that touchy temperament to their advantage. In the final product, frigid LH2 does two jobs as it courses toward ignition. First, it is pumped through an outer jacket where it cools the thrust chamber's fierce 6,000° heat, and in the process vaporizes itself for ultimate burning. But before it reaches the chamber, the gas is expanding fast enough to spin an auxiliary turbine, which pumps more fuel and oxidizer into the cooling jacket. Thus the LH2 practically lifts...
...Joyce Pratt, manager of the Brattle, said that no increase in price for movie tickets or refreshments downstairs was envisioned. The greatest changes will be downstairs, where the lobby next to the Blue Parrot will be made three times as large and the passageway to the Casablanca will be three feet wider, the new lobby will be paneled, and the entire downstairs floor covered with wall-to-wall carpeting...
...courses suffer the same fate of constriction. Gov. 213a looks at "Social Theory from Marx through Freud" with the vision of Barrington Moore. An all-star cast of Raiffa, Schlaifer, and Pratt will discuss decision theory in Stat. 288. And in response to the first commandment, "Let there be light," we have Via. Stud. 145, "The Flics," courtesy of R. G. Gardner. Harvard students are lucky to have such a pious faculty...
Deborah Camp beat Virginia Pratt to become a finalist in the women's singles division. Miss Camp will play against Lin Morss, who defeated Penny Kennedy in the semi-finals...