Boyd is, however, a controversial figure. Among USAF officers, Boyd is either loved or hated. Hammond’s introduction refers to him as ‘legendary,’ ‘a great original thinker,’ and ‘a paragon of virtue – loved by many […] for his character and integrity.’ On the other hand, former fighter pilot and USAF Chief of Staff General Merrill McPeak summarised the opposing view: ‘Boyd is highly overrated […] In many respects he was a failed officer and even a failed human being.’ …
Boyd’s first significant contribution to USAF thinking was ‘Energy Maneuverability Theory’ (EMT) in the early-to-mid 1960s. This was an application of the principles of thermodynamics to aircraft metrics. Up until that point, the most important metrics for evaluating fighter planes tended to be wing loading ratios, top speed, and acceleration. Many fighter pilots tried to argue that agility and manoeuvrability were more important in a dogfight, but although wing loading could provide a rough idea of how well a craft could turn, it fell far short of an accurate description of a plane’s manoeuvrability. Boyd’s EMT instead analysed how well an aircraft could change energy states – involving speed, acceleration, kinetic and potential energy – essentially giving a numerical value to how well a plane could manoeuvre under various conditions. Charting this value on a graph corresponding to speed and altitude will give a curve of the aircraft’s manoeuvring capability. This method gave fighter pilots a way to talk to engineers in their ‘language,’ and describe dogfighting in mathematical terms, which had a significant influence on aircraft design. Beginning in the late 1960s, EMT became a significant factor in designing and evaluating American aircraft.
Although Boyd appears to have come up with these ideas independently, he was not the first to do so. A decade earlier, in 1954, an aerodynamics engineer working for Douglas named Edward Rutowski had the same concept. Rutowski’s work did not apply to dogfighting, but to calculating fuel ranges of various types of aircraft. However, the equations – and the charts – are almost the same as Boyd’s, who later admitted to copying the charts after denying it for years. One element that Boyd did add, however, was overlaying the EMT curve for one aircraft on top of another, to show where one aircraft had an advantage in manoeuvrability. These comparisons, first done in the late 1960s, showed that Soviet aircraft of that time might have a distinct advantage in dogfighting compared to the American fighters of the day (which, in that period, were mostly interceptors, not traditional fighters). Thus, while not necessarily completely original, Boyd did more to popularise the EMT concept and apply it to fighter design and tactics training, which then became part of a push within the USAF to design aircraft that were more specialised for air-to-air combat.
Read the whole thing by Michael Hankins, then read the uproar in the comments. It appears that we are unclear whether there was independent discovery of EM Theory’s equations between John Boyd and Rutowski, but Boyd subsequently admitted to using Rutowski’s charting methods, which he later upgraded. The author cites the following resource:
USAF Historical Research Agency, K239.0512-1066, John Boyd, Corona Ace Oral History Interview, 22 January 1977.
Boyd isn’t in the Air Force’s oral history catalog. Would be nice if that would be made available.
Here is a part from Winslow Wheeler in the comments:
… in Desert Storm General Horner and his staff made it clear to F-16 pilots that “the first F-16 pilot that goes air-to-air goes home.” That was a quote given to my GAO research team that looked at the air campaign for Desert Storm. I will admit the reference is hard to find, but the Air Force’s climate of anxiety about the F-16 as a competitor to the F-15 as a fighter is not. One has to question why that is not an issue you discuss in writing about Boyd.
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