H UMAN F LIGHT &ROBOTIC E XPLORATION “Pioneering Space” Part II By Gideon Marcus research determined that 108 had experi- days for Earth and Moon to be in similar enced the same problem. This discovery did respective positions again. The launch win- An Unnumbered Pioneer not come as a complete surprise. Dolph dows were so narrow that mission planners Just six months after Louis Dunn Thiel, propulsions expert at Space had long since decided to not provide trajec- gave the order to start production, through Technology Laboratories and Peenemünde tory compensation for launch holds. dint of hard effort and ingenuity, the first veteran, had noted early that year that Instead, each Thor was preprogrammed Thor-Able three-stage booster towered 88 Thor’s turbopump design was thoroughly with a particular roll program, which varied feet above Launch Complex 17 pad A on marginal and recommended that the prob- depending on the launch day. The Air Force Merritt Island, Florida. The serial number, lem be fixed in the next run of the Thor mis- took for granted that the rocket would be 127, was printed on the Thor IRBM first sile. The problem was that several of the ready to fire at the proper time.2 stage, and USAF was proudly emblazoned potentially faulty Thors had already been Able-1’s first countdown went by along the Vanguard second stage. Atop the built and were committed for a variety of almost without a hitch. The Thor-Able third stage rested the world’s first lunar missions: several test flights, two more booster was fully fueled by the afternoon of probe. Roy Johnson, head of ARPA, and ARTV flights—and the Able-1 lunar 16 August. Engine and electrical checks U.S. Air Force Major General Bernard probes. were begun at 1930 and completed ahead of Schriever, who directed the first U.S. ICBM Should the Thor flights continue or schedule. On launch day, at T-35 minutes, programs, were among those in attendance. be suspended? That was the critical decision interstation communications were checked. The general was apprehensive about facing General Schriever. Fourteen Thors All stations reported that they were ready this flight and with good reason. In October had been launched thus far. Two had failed for operations, though the link to Singapore 1957, Thor 108 inexplicably exploded in in flight. Statistically, each Thor had a one- was somewhat noisy. mid-flight. Six months later, the first ARTV in-seven chance of exploding. Grounding At around the same time, telemetry Thor-Able blew up 146 seconds into its the Thor would cause several months of modulation of the Able-1’s low-frequency flight. This time, the malfunction was linked delay in a number of projects. On the other transmitter mysteriously ceased, the antenna to the Thor’s turbopump gearbox. Further hand, even in the event of the loss of one or instead locking on to a local, low-level two missiles, valuable guidance data could transmission. At T-15 minutes, a short hold be gathered. The only hard decision was called to turn off local telemetry involved the three Able-1 missions. General receivers in the hopes that they were attract- Schriever decided the odds were good ing the probe’s transmitter, but the problem enough, and ordered no delays, balancing persisted. The payload’s Doppler receiver the risk of a public relations disaster against did lock just fine when the local ground the benefits of accelerated development.1 transmitter was turned on. It was ultimately Seconds ticked by as the launch time concluded that there was some low level grew ever closer. The countdown was a “T- interfering signal unrelated to the transmit- minus” system with built in holds before the ters and receivers at the blockhouse. launch time as opposed to the older variety, Mission controllers ultimately decided that which pushed the launch forward with every the problem was not a large one and that it delay. This type of countdown is common- would likely correct itself after takeoff any- place now, but at the time this was a new way. No further problems were encountered innovation developed to accommodate mis- during the countdown and Thor 127’s sions with inflexible launch windows, lunar motors ignited at 0718 on August 17, four shots being among them. Hitting the vicini- minutes behind schedule.3 ty of the Moon from the rapidly spinning As America’s first lunar mission surface of Earth is a complicated billiard began its stately ascent from Pad 17-A, the shot. The opportunity to reach lunar orbit mood became jubilant. At 73.6 seconds comes only four days out of every month, later, elation turned to horror. The main and there is only a 35-minute window on bearing on the first stage’s turbopump, driv- Carl McIlwain Image courtesy of Gideon Marcus even the best of those days. If they missed en by the intense revolutions of the pump the window, the launch crew must wait 28 shaft, walked its way out of its housing and Q U E S T 14:3 2007 18 tore Thor 127 pieces—the same disaster that restrial molecules might had befallen Thors 108 and 116. The mis- adversely affect life or pre- sion was over. General Schriever had lost life processes on the Moon his gamble. Dolph Thiel placed his head in was justification enough his hands and sobbed.4 for the precaution.7 The next flight was optimistically At the Cape, Dr. planned for mid-September. This date was George Mueller, director of pushed to mid-October, which among other the Able-1 project at STL, things gave Van Allen’s team time to com- and U.S. Air Force plete its ion counter experiment. Lieutenant Donald Latham directed launch operations, Pioneer 1 Flies their 40-person crew com- Two months after the failed flight of pleting readiness checks Able-1, Thor 130 stood ready on the pad. with all STL ground sta- Though President Dwight Eisenhower had tions the day before launch. created the National Air and Space In addition to the primary Administration on 29 July 29, and on 1 tracking stations at October 1958 the new agency officially Canaveral, Hawaii, took control of all civilian space missions, Singapore, Manchester, the Thor-Able booster still bore the letters and Millstone (NH), ten “USAF” on the second stage. Its payload, Vanguard Minitrack sta- however, did receive a new name. The tions in Peru, Antigua, Army’s series of satellites was called Chile, Ecuador, the “Explorer” and their public information Bahamas, South Africa, officer proudly proclaimed them the Texas, Havana, and “Pioneers in Space.” Stephen A. Saliga, Australia stood by to relay chief designer of Air Force exhibits at the tracking data through the Pioneer 0 launch assembly Image courtesy of Gideon Marcus Air Force Orientation Group, Wright- Cape.8 Preparations contin- Patterson AFB, suggested the Air Force ued right up to launch time. onds of fuel left in the second stage.11 At show who the real Pioneers in space were At one point, the Ramo-Wooldridge man in the time, no one knew what caused the first by naming the new lunar orbiter, charge of the Hawaii station reported that stage loft. Wind was suggested as the cul- “Pioneer.”5 His proposal was accepted, and the antenna there was frozen. Mueller prit,12 but the Air Force later concluded that under this new naming scheme, the Able-1 laconically replied that the man had 12 the problem was caused by the first-stage flying in October would be known to the hours to fix it, or they would launch any- autopilot.13 By third-stage burnout, some- world as “Pioneer 1.” In the interests of con- way. The antenna was repaired in time for thing was seriously amiss, though it took sistency, the failed August flight was desig- the launch.9 some time for the mission controllers to nated “Pioneer 0.” The countdown proceeded largely ascertain this. The velocity vector was off As with Pioneer 0, all concerned without incident. Ten seconds before dead- some 5 degrees now. Somehow the third felt great trepidation about the launch— line, there was a momentary hold: a super- stage had been cocked from center some 15 more so now that they’d already lost one of visor had not responded to one of many degrees after separation from the second their three spacecraft. Unlike the August thumbs-up signals in the blockhouse. The stage. This deviation from the planned flight mission, Pioneer 1’s flight was a matter of countdown resumed a few seconds later path presaged failure for the spacecraft’s public scrutiny. If all went well, the space- with no further problems. At 4:42 a.m. east- primary mission. craft would be the world’s eighth space mis- ern daylight time, Saturday, 11 October As of third-stage burnout, Pioneer sion, America’s fifth, and the first to 1958, NASA’s first space probe departed its was traveling at some 500 ft/sec less than approach the Moon, much less orbit it. All launch pad only 13 seconds behind sched- the desired 35,206 ft/sec, which would eyes on both sides of the Iron Curtain wait- ule.10 allow it to escape Earth’s gravity. All eight ed to see if America’s first civilian lunar Just 16 minutes later, all three stages vernier rockets, designed to keep the probe shot would be a success or not. Professor on the Thor Able had fired successfully. At on course, were fired to make up deficit.