The NACA achieved early success and acclaim by developing revolutionary wind tunnels for aerodynamical research. Thereafter the tunnels took on a life of their own, influencing the pace and direction of NACA research; concentrating the Committee's attention on aerodynamics when fields like propulsion, structures, and helicopters had equal merit; and becoming in time a sort of end in themselves. The NACA used its wind tunnels to great advantage, but the wind tunnels also used the NACA.

This study is both a narrative history-the author's account of what was significant in the career of the NACA—and a reference work from which the essential facts of the Committee's history can be readily retrieved. To keep the one function from intruding on the other, most of the factual data on the NACA appear in appendixes: all the major legislation affecting the Committee, the committee structure and composition, the budget and personnel histories, the facilities, the details of the NACA research process and its resulting reports, and a selection of representative and significant documents. In appendixes, this information is easier to find and does not clutter the text, which is a comparatively brief, interpretative, and analytical survey of the Committee's history directed at specialists and nonspecialists alike.

This history has been written primarily from the records of the NACA headquarters, supplemented with extensive research in the records of the NACA laboratories, in the records of other agencies and institutions, and in the secondary literature, which is lamentably sparse. But the primary perspective is that of headquarters. It was, after all, the headquarters that ran the NACA, and it is in these records that the course of NACA history can be traced most readily and fully. This account might have benefited from further research in the records of the laboratories and of the NACA's principal clients, the military services and the aircraft manufacturers. But preliminary consultation of these sources suggested that additional research would merely have confirmed the broad conclusions reached here and would have complemented, not altered, the story. Furthermore, one purpose of this book was to serve as a guide to the records of the NACA, introducing them to other researchers in related fields; that purpose was best served by making the fullest possible use of the NACA material.

Only a handful of the major characters are mentioned in the text. By design, the men and women of the NACA worked as a team, collaborating freely across institutional and disciplinary boundaries and editing each other's work until the published reports were as uniform and impersonal as a military training manual. By all reports, the people of the NACA had as much humor and liveliness as any comparable group, but it was not the kind of humor that comes across on paper, in the few instances where it was allowed in print at all. It was instead an

engineer's humor, narrow, esoteric, almost sophomoric, evoking gales of laughter from the initiate with punchlines like ". . . but he had given him a screw with a left-handed thread." Mostly, the record of the NACA is dry, correct, impersonal, and colorless. The few personalities that do emerge to influence the course of events are described in the text. Other key people of the NACA are named in Appendix D.

Participants in the story have been quoted at length-even, at times, without being identified-to give the reader an opportunity to interpret some of the material for himself and to convey the flavor of the literary style of the engineer, who writes with a safety factor of three. As if building a bridge that can in theory support three times the weight it is expected to bear, the typical engineer builds a sentence with enough words to repeat his message twice. Aeronautical engineers generally deal with a safety factor of 1.5 but their sentences tend to be no less weighty than those of their civil and mechanical colleagues.

One of the author's principal aims has been to keep the text brief, nontechnical, and on course. Supplementary material—illustrative quotations, historical asides, debating points, technical data, and comments on the sources-may be found in the notes, along with the normal documentation of the text. The specialist can consult the notes to amplify topics of particular concern to him; the general reader also may find the additional information interesting and rewarding. The NACA was a long-standing house of many rooms, not all of which could be fully explored in a text of this compass.

Finally, some home truths about the style and tone of this study. One NACA veteran, commenting on the manuscript, guessed that “in his heart of hearts Roland simply finds more interest and excitement in NACA's failings than in its successes." There is more than a little truth in that observation. In researching and writing this book, I was much more alive to the NACA's shortcomings than I was to its virtues.

I did not consciously plan to emphasize the negative; rather, that pattern emerged from three separate but related causes. First, as a kept historian in the employ of the agency about which I was writing, I set out with a personal and professional interest in demonstrating that official history need not be court history, that the agency historian (at least in this agency) can be critical and independent, that he can contradict the party line when the evidence warrants it without fear of censorship or recrimination. This ambition may well have led me to be overzealous in finding fault with the NACA. The good news is that I have at least proved my point-perhaps at the expense of the NACAfor NASA readily agreed to publish the manuscript, an excess of warts notwithstanding.

Second, the headquarters records-the source on which I relied most heavily-are enough to raise the hackles of even the most sympa

thetic historian. They are filled with myopic, self-serving, politically motivated propaganda. I can appreciate that the NACA was forced into this public posturing by the nature of pluralistic politics in Washington, that all government agencies engage in such practices, and that work in the laboratories was generally untainted with the grime of public relations. Still, one cannot immerse himself in those records for several years without wanting to puncture the balloon of self-aggrandizement that was inflated in the NACA headquarters.

Finally, I remain seriously concerned about the ability of the official record to convey a critical picture of the NACA. Virtually all those in a position to knowledgeably assess the Committee had a vested interest in keeping their objections and misgivings to themselves. The NACA was not anxious to air its dirty laundry, and I think the desire to emphasize the positive finally produced an inability to acknowledge the negative-at headquarters, certainly, and to a lesser degree in the laboratories. Those in industry and the military services who relied on the NACA had every reason to praise the Committee in public lest their criticisms contribute to either a decline in the Committee's budget or a reluctance on the part of the Committee to do the work they wanted. With the possible exception of academics, I can think of no contemporary group likely to criticize the NACA freely and knowledgeably. If my book seems overly critical, it is partly to correct this imbalance in the public record.

In revising my manuscript for publication, I have sought to eliminate the imbalances, both pro and con, that appeared in the work. Some harsh judgments simply will not wash out; some bouquets are no doubt sweeter than they should be. In sum, the NACA that appears in these pages corresponds as closely as I could make it to the one I found in the Committee's files. Readers may decide for themselves to what extent it was a model research organization.

Acknowledgments

This book owes much to many hands besides mine. First among those who aided in its preparation is Walter T. Bonney, from whom I inherited the project. The former head of public affairs for the NACA and NASA, Walter undertook to prepare in his retirement under contract to the NASA History Office a history of the NACA. He had completed his research, outlining, and the drafting of three chapters at the time of his death in 1975. This book is not the one that Walter envisioned, but it has drawn heavily on his research and insights.

In the course of my own research I incurred countless other debts, only a few of which may be acknowledged here. The greatest is to Steve Bern of the Washington National Records Center, who personally pulled from the shelves and delivered to me all 480 of the boxes of NÁČA records I examined at Suitland. In their years of storage, many of these boxes had accumulated inside and out a clinging layer of fine, silty, black dust that blew up when the boxes were disturbed to settle down tenaciously on the lungs, hands, and clothing of any who dared to disturb them. Steve was chosen for this unpleasant job because he was the youngest, strongest, and most good-natured hand at Suitland. He performed with unfailing dispatch, accuracy, and good humorlightening for me an otherwise onerous research task. His supervisor, James Miller, made both our jobs easier in countless ways. William Lewis facilitated the temporary loan of some of the more important boxes so that I might examine them more closely in my office.

Equally helpful service was provided at the National Archives main building by Marilla Guptil, William Cunliffe, and Lee Johnson. The staffs at the Federal Archives and Records Centers in San Bruno and Luna Niguel, Calif., did the same.

The late Alfred E. String made the NASA Headquarters Technical Library a productive place to work and helped me gain access to the resources of the Library of Congress. Grace Reader, Eleanor Burdette, and Mary Anderson were unfailingly helpful and solicitous in digging out material in the Headquarters technical library or in drawing items from other NASA libraries or libraries outside the agency. Walter Bonney spoke often of how helpful Grace Reader had been to him; Eleanor Burdette was especially helpful to me in unraveling the NACA filing system for technical publications.