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tion, the Applied Physics Laboratory developed and used a much smaller, 6-channel, frequency-modulated telemeter.3

Radar beacons were installed in the missile to track it, providing information on where measurements had been made. The range also required that each rocket be outfitted with a special radio receiver that could cut off the motor should the missile begin to misbehave after launch. Arrangements had to be made for building and supplying this equipment. Also, to supplement the tracking information provided by radar and radio, theodolites, precise cameras, and other optical instruments were installed at strategic locations along the firing range to furnish both visual and photographic trajectory data. It also would be essential to know the orientation of the rocket in order to interpret properly such measurements as aerodynamic pressures or cosmic ray fluxes. For this, still more instruments— including photocells to observe the direction of the sun, cameras, and magnetometers-were brought to bear.4

Although much, perhaps most, of the scientific data would be obtained by telemetering, some measurements would require the recovery of equipment and records from the rocket after the flight was over, such as earth and cloud pictures, photographs of the sun's spectrum, and biological specimens exposed to the flight environment. For this purpose several techniques were developed, including the use of explosives to destroy the streamlining of the rocket, causing it to maple leaf to the ground; the deployment of parachutes to recover part or all of the spent rocket; and even the application of the kind of sound ranging techniques used in World War I to locate large guns.5

At first, operations at White Sands were an amorphous collection of activities. During the first year of rocket sounding the procedures and issues that would have to be dealt with in even greater detail years later in the space program emerged: safety considerations, provision for terminating propulsion of the missile in mid-flight, tracking, telemetering, timing signals, range communications, radio-frequency interference problems, weather reports, recovery of instruments and records, and all that went into assembling, instrumenting, testing, fueling, and launching the rocket. To cope with the seemingly endless detail, the range required formal written operational plans in advance that could be disseminated to the various groups. A more or less standard routine evolved with which the participants became familiar. In only a few years experimenters were harking back to the "good old days" when operations were free and easy and red tape had not yet tied everything into neat little, inviolable packages.

While the General Electric Company personnel, Army workers, and others labored to produce successful rocket firings, the scientists labored equally hard to devise and produce the instrumentation that would yield the desired scientific measurements. At first some of the instrumentation was tentative, even crude, as when Ralph Havens of NRL took an auto

mobile headlight bulb, knocked off the tip, and used it as a Pirani pressure gauge to measure atmospheric pressure in the V-2 fired on 28 June 1946. But even before the end of 1945 spectrographs were recording the sun's spectrum in previously unobserved ultraviolet wavelengths, special radio transmitters were measuring the electrification of the ionosphere, and a variety of cosmic-ray-counter telescopes were analyzing radiation at the edge of space. A portion of each panel meeting was devoted to reporting on experimental results, which accumulated steadily from the very first flight of 16 April 1946. Papers began to appear in the literature and attracted considerable attention as experimenters reported on measurements that hitherto were impossible to make.7 By the time the last V-2 was fired in the fall of 1952, a rich harvest of information on atmospheric temperatures, pressures, densities, composition, ionization, and winds, atmospheric and solar radiations, the earth's magnetic field at high altitudes, and cosmic rays had been reaped.8

THE NEED TO REPLACE THE V-2

But not all of the results had been obtained from the V-2. To be sure, the immediate availability of the V-2 as a sounding rocket was a boon to the program, for it meant that the scientists could start experimenting without delay. Its altitude performance of 160 kilometers with a metric ton of payload far exceeded that of any other rocket that the experimenters might have been able to use, making investigations well into the ionosphere possible from the outset. More significantly, the large weightcarrying capacity of the rocket meant that experimenters did not have to miniaturize and trim their equipment to shoehorn them into a very restricted payload, but could use relatively gross designs and construction. This capacity was a great help at the start, when everyone was learning, for it permitted the researcher to concentrate on the physics of his experiment without being distracted by added engineering requirements imposed by the rocket tool. Later, with some years of experience behind him, the experimenter would be able to take the outfitting of much smaller rockets in stride. And it was of advantage to go to smaller rockets as soon as possible.

Smaller rockets would be much cheaper, far simpler than the V-2 to assemble, test, and launch. Moreover, with the smaller, simpler rockets the logistics of conducting rocket soundings at places other than White Sands would be manageable. With such thoughts in mind, as panel members pressed the exploration of the upper atmosphere with the V-2 they also set out to develop a variety of single and multistage rockets specifically for atmospheric sounding.9 James Van Allen and his colleagues at the Applied Physics Laboratory undertook, with support from the U.S. Navy's Bureau of Ordnance, to develop the Aerobee sounding rocket.1o At the same time NRL took on the job of developing a large rocket-first called Neptune,

but later Viking when it was learned a Neptune aircraft already existed-to replace the V-2s when they were gone." At the 28 January 1948 meeting of the panel, Van Allen reported on a series of test firings of the Aerobeethree dummy rounds and one live round.12 As soon as it was ready the Aerobee was put to work exploring the upper atmosphere and space, with firings not only from the original Aerobee launching tower at White Sands, but also from a second tower that the Air Force erected some 57 kilometers northeast of the Army blockhouse at the White Sands Proving Ground. The Air Force tower was located at Holloman Air Force Base near Alamogordo. Not content with the payload and altitude capabilities of the first Aerobees, both the Air Force and the Navy continued the development, producing something like a dozen different versions, one of which could carry 23 kilograms of payload to an altitude of 480 kilometers. 13 In its various versions Aerobee was used continuously in the high-altitude rocket research program through the 1950s and 1960s and was still in use in the mid-1970s.

In contrast, the Viking, although of a marvelous design-Milton Rosen, who directed the Viking development program, used to point out that in its time Viking was the most efficiently designed rocket in existencefound very little use. The dozen rockets bought for the development program were, of course, instrumented for high-altitude research. But Viking was too expensive. The groups engaged in rocket sounding each had perhaps a few hundred thousand dollars a year to expend on the research, and a single Viking would have eaten up the whole budget. When the supply of German V-2s began to run low, consideration was given to building new ones; but estimates placed the price per copy at around half a million dollars, which was prohibitive. It had been hoped that Viking would be much less expensive, but before the end of the development these rockets became almost as expensive as new V-2s. So Viking found no takers among the atmospheric sounding groups and would probably have been shelved had it not been chosen as the starting point for the Vanguard IGY satellite launching vehicle.14

The contrast between Viking and Aerobee typified a situation that has recurred in the space science program. One group of scientists would favor developing large new rockets, spacecraft, or other equipment that would greatly extend the research capability. Another group would prefer to keep things as small and simple as possible, devoting its funds to scientific experiments that could be done with available rockets and equipment. The former group could always point to research not possible with existing tools, thus justifying the proposed development. In rebuttal the latter could always point to an ample collection of important problems that could be attacked with existing means. There was right on both sides of the argument, and it was usually a standoff. As far as upper atmospheric research was concerned, however, Viking was too far ahead of its time.

While in the next decade researchers would be able to buy $1-million Scouts (chap. 10), in the early years of rocket sounding Viking cost too much.

Once the ball had started rolling with Aerobee and Viking, other rocket combinations began to appear. The experimenters sought less cost, greater simplicity, higher altitudes, more payload, and especially a capability to conduct firings at different geographic locations. Great ingenuity was displayed in putting together new combinations. Sounding rockets were taken to the California coast, to Florida, to the Virginia coast, out to sea, and to the shores of Hudson's Bay in Canada. 15 They were even launched in the stratosphere from balloons, a combination that the inventor, Van Allen, called a Rockoon.16 In the panel meeting of 9 September 1954, Van Allen reported that Rockoon flights in the Arctic had established the existence of a soft radiation in the auroral zone above 50 kilometers height, which proved to be one of the milestones along the investigative track that ultimately led to the discovery of the earth's radiation belt.

SCOPE OF PANEL ACTIVITY

One of the most notable aspects of the panel record is the steadily increasing scope of activity. In the minutes of the organizing meeting, the secretary referred to the group simply as "the panel." By the third meeting Megerian was calling the group the "V-2 Upper Atmosphere Panel." This name continued for the next two meetings; but the appellation "V-2 Upper Atmosphere Research Panel" appeared at the sixth meeting, in September 1946, and stuck for the next year and a half. These first titles reflected the panel's participation in the V-2 program, but the group's primary business was high-altitude research, not V-2s. The panel, well aware that the supply of V-2s would be exhausted in the not too distant future, gave early attention to finding alternative sounding rockets. Prodded by the Office of the Chief of Ordnance, at its March 1948 meeting the panel dropped the V-2 from its title and began calling itself the "Upper Atmosphere Rocket Research Panel" (UARRP). This sufficed to describe activities until members had become so thoroughly involved in the International Geophysical Year scientific satellite program that another name change seemed appropriate. At an executive session, 29 April 1957, the panel adopted its final name: "Rocket and Satellite Research Panel."'17

Throughout most of its active life, the panel remained quite small. By restricting its rolls to working members only, and also by limiting the number of representatives from any one agency, the panel kept its size down-which made for more manageable meetings. Yet there was no desire to limit interest or participation in the meetings. A loyal cadre of observers attended the sessions throughout the years and joined in the discussions. From the first, the National Advisory Committee for Aeronautics was repre

sented among the observers-an interesting fact in retrospect, although at the time there was no reason to suspect that one day NACA might play a central role in a suddenly emerging space program. Increasing interest in high-altitude rocket research over the years is also shown by the steady growth in the list of addressees to whom panel reports were sent. The minutes of the organizing meeting went to only about 30 persons; 10 years later some 118 copies were being distributed among 73 addressees. 18 The composition of the distribution lists is illuminating (see app. B). The military was obviously interested. So, too, were other government agencies such as NACA and the U.S. Weather Bureau. The large number of university names on the list no doubt resulted from the pure-science nature of much of the panel's research.

For more than a decade the panel occupied a unique position in scientific research. In the United States its members represented all the institutions engaged in sounding rocket research. Attendees at meetingsmembers plus observers-comprised a substantial number of the individuals in the country who were involved. As one consequence of this unique position, the panel came to be regarded as the prime source of expertise in the field. In spite of the lack of any official charter, the panel soon acquired a quasi-official status. The National Advisory Committee for Aeronautics used data from the panel program in compiling and updating its tables of a standard atmosphere. 19 The Defense Department's Research and Development Board made a practice of turning to the panel for recommendations regarding sounding rockets and high-altitude rocket research. The board-called the Joint Research and Development Board before the establishment of the Department of Defense in 1947-boasted a sprawling, complex structure intended to correspond in one way or another to the military research and development programs.20 From time to time its Committee on Guided Missiles took an interest in the rockets being used by the panel. When, in the spring of 1949, the Navy's Viking and the Air Force's MX774 rockets came into competition-it was not considered reasonable for the country to support two large, expensive sounding-rockets—UARRP was informed that a panel of the Committee on Guided Missiles endorsed Viking. The R&D board's Committee on Geophysical Sciences, and its subsidiary group for study of the upper atmosphere, took a continuing interest in what UARRP was up to. The subsidiary group endorsed the UARRP's research program and in November 1947, responding to a request for support, unanimously recognized "the importance of all phases of the well-coordinated V-2 rocket firings program and the grave consequences of any failure to give adequate financial support to all agencies involved in this program, since the lack of support of the program in any one agency would jeopardize the program as a whole."21 At its April 1950 meeting, one finds the UARRP responding

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