Both Atlas and Centaur had a unique thin outer skin that relied on internal pressurization to maintain its shape. Marshall had had serious reservations about this balloonlike design and indicated that winds of less than 2 knots could require launch restrictions.344 With the acquisition of the Centaur Program in the fall of 1962, Lewis wanted to test the Atlas/Centaur’s structural integrity in their new E Stand.
Lewis engineers designed E Stand to accommodate full-scale missiles, but it was not large enough to hold a missile and an upper stage. NASA provided $875,000 from the Centaur transfer budget to modify E Stand. The alterations included extending the height of the stand by 27 feet, adding a 110-foot-tall rolling door (then the nation’s largest), strengthening the support structure and weather protection, installing a new hydraulic shaker, and improving the data acquisition and fluid pumping systems.345
There was intense pressure to complete the modifications, which began in May 1963, in time to test the Atlas/Centaur before the launch scheduled for November 1963. The delayed shipment of new equipment strained the Rocket Systems Division’s resources and schedule. After working 14-hour days throughout the summer, the crew completed the work on time in August.346
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The Centaur Program Office first needed to verify that the Atlas booster could handle a heavy stage like Centaur. “The Centaur weighs about 39,000 pounds loaded,” explained Bruce Lundin. “Under six G’s this will mean a quarter of a million pounds pushing down on the Atlas booster. This is nearly twice as much load as Atlas ever carried before. We don’t want to learn in flight that it is not strong enough to carry the load.”347
On 31 July 1963 a General Dynamics trailer and police escort delivered an Atlas to Plum Brook.348 Plum Brook technicians replaced the Atlas engines with mass models and hoisted the booster into E Stand in August 1963.349 On 11 October 1963 the Atlas structure withstood 248,000 pounds of pressure, the maximum force that would be experienced in flight. The test was successfully repeated with the addition of heating elements to simulate aerodynamic heating during launch. The engineers then subjected the Atlas to a maximum-bending test without any issue. The Rocket Systems Area Test Operations Report noted, “During the month of October, several important test milestones were passed, all of which culminated in lifting of the flight restraint for AC-2 [Atlas/Centaur 2].”350
Image 79: Atlas missile is delivered to Plum Brook in July 1963. The vehicle had to avoid tight turns, most bridges and underpasses, and large urban areas during its 2,500-mile trek from the General Dynamics plant in San Diego to Sandusky. (GRC–1963–C–65589).
Image 80: General Dynamics designed a unique 64-foot- long cradlelike trailer to transport the missile. It was so large that additional drivers were placed at the rear of the trailer to guide it around turns (GRC–1963–P– 01708). 351
Meanwhile, the Rocket Systems Division staff rushed to reconfigure the E Stand setup for the next series of tests, which would include both the Atlas and Centaur. An actual Centaur was not available in time for these runs, so the researchers used a model with simulated propellants in the tanks.352 In mid- November the Atlas/Centaur successfully withstood a series of longitudinal vibration tests.353
Image 81: Installation of Atlas stage into E Stand in August 1963. The vehicle had to be pressurized during the process to avoid damage to the aluminum shell (GRC–1963–P–01716).
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On 27 November 1963 Silverstein joined more than two dozen Lewis engineers at Cape Canaveral for Lewis’s first attempt at launching a Centaur (AC–2). Ninety other Centaur staffers monitored the proceedings from the hangar in Cleveland. The Centaur Program Office had spent the previous 13 months preparing for the launch, which had been delayed by the assassination of President John F. Kennedy the previous week.354
A scrub appeared eminent as cloud cover forced the suspension of the countdown in the morning. The skies cleared around noon, however, and the countdown resumed. At 2:03 p.m. the 109-foot-long Atlas/Centaur roared into the sky. Four minutes and twenty seconds later the Centaur upper stage separated from the booster and raced into orbit, where it remains in 2016. The Lewis personnel burst into cheers, and NASA managers breathed a sigh of relief.355 Centaur was back on track, and Lewis proved it could manage a large rocket program. The AC–2 launch was most significant, however, as the first full- scale demonstration that liquid hydrogen could be used as a propellant.
Image 83: Centaur E Stand Project staff receives Lewis’s first ever Agency-wide Group Achievement Award on 23 June 1964. The 12-person group was cited for “significant contributions resulting in the successful completion of research testing of the Atlas 116 D booster under simulated loading and environmental conditions and providing data vital to the first flight of the Centaur vehicle.” Front row, left to right: George Thomas, Alvin Schultz, Abe Silverstein, Alan Johnson, and William Thompson. Back row: Glen Hennings, Russell Koger, Joseph Gillete, Norman Schroeder, Darrell Baldwin, Lawrence Gentile, Donald Cooksey, and Robert Siewert (GRC–1964–P–01398).
Image 82: AC–2 launch on 27 November 1963. It was Lewis’s first launch attempt and the first successful launch of a liquid hydrogen- fueled rocket (NASA).