Sometime in 1978, I was thumbing through an issue of Esquire magazine and it fell open to an excerpt from Tom Wolfe’s “The Right Stuff.” The book would appear the following year. Esquire picked Wolfe’s breathless recounting of Chuck Yeager’s historic Mach 1 flight in the X-1. Today, October 14, is the 73rd anniversary of that flight. That Yeager’s flight and the man himself were a revelation to Wolfe led to the line in the movie version, “They were called test pilots. And no one knew their names.”

Perhaps that was true of the freckle-necked masses, but it wasn’t true for this aviation-obsessed first-grader. Might have been second grade, which would have been 1957, 10 years after the fact. I certainly knew who Chuck Yeager was, what the X-1 was and how the two connected because I had read it in one of those Golden Books about aviation that I absorbed instead of my phonics reader. According to my second-grade report card which, improbably, I still have, I nonetheless got a B+ in reading, thanks to the merciful pioneering efforts of Sister Mary Clare in the field of self-esteem boosting participation trophies.

Even today, knowing who Yaeger was and what he did would constitute deep knowledge. Although he got the glory—and continues to—he was but the point of the spear. The actual flight occurred on Oct. 14, 1947, but the government suppressed the announcement until the following June. Later that year, the X-1 team was awarded the Collier trophy. The black-and-white press grip-and-grins of the day show Yeager shaking hands with Harry Truman, but who are those other two guys who shared the trophy?

The one on the right is Larry Bell whose Bell Aircraft designed and built the X-1. The one on the left is John Stack. John who? Even I admit I knew the name, but didn’t quite know the history. Stack was an aeronautical researcher who joined NACA—the precursor to NASA—in 1928, a year after Lindbergh flew the Atlantic. At a time when a fast airplane was tooling along at 150 knots, Stack’s interest was in high-speed flight and eventually the problems associated with compressibility and shock wave effects on airfoils at high speed. Much of it centered on propellers, whose tips approached and exceeded Mach 1.

Contrary to popular belief, as revealed in John D. Anderson’s “From Engineering Science to Big Science: The NACA and NASA Collier Trophy Research Project Winners,” the X-1 era wasn’t entirely pioneering new knowledge on shock waves but applying what had already been discovered. Almost 60 years earlier, in 1887, the Austrian  physicist  Ernst Mach had photographed a shockwave from a speeding bullet and developed rudimentary data on its characteristics. For his efforts, he got his own number, but not until 1926, when a Swiss aeronautical engineer named Jakob Ackeret made it so.

Stack’s original idea for a high-speed research aircraft.

Throughout the 1930s, Stack and his NACA boss, Eastman Jacobs, toiled creatively in developing wind tunnels capable of high-speed flow. One of these eventually became the famed “11-inch,” a tunnel that could sustain about a minute of high-speed flow using air from a giant compressed tank. Since no aircraft were directly envisioned and neither were the X-planes, this was pure research for the sake of investigatory curiosity. It wouldn’t remain thus.   

Among Stack and Jacobs’ numerous discoveries were that the air behind a shock wave departed the airfoil surface and dramatically decreased lift and increased drag, a problem that would reveal itself in the X-1’s earlier tests and before that in the notorious compressibility problems in the wartime P-38. This was, at the time, called a shock stall.

As early as 1934, using a schlieren photographic system, Stack produced a photo of a shock wave acting on an airfoil in the transonic region. It was a fuzzy picture but the implications were unmistakable and according to Anderson’s reporting, these discoveries electrified the aeronautical research world. A curious graph of the day depicted two drag curves, one rising and one descending. The first was the subsonic regime, the second the supersonic. In between was the “unknown,” the transonic gap.

As early as 1933, Stack proposed a theoretical pure research airplane that eventually led to the X-1. On paper, he called for a turbojet aircraft that could take off under its own power and have a maximum speed of Mach 1. By the time Bell Aircraft got hold of the idea in 1944, the airplane was to be rocket-powered and air launched from a B-29. And thus was born not just the X-1, but a series of rocket-powered research aircraft culminating in the X-15, whose 199 flights generated data that helped buoy the space program and put Americans on the Moon.

So as we observe Supersonic Day, we should remember that although Chuck Yeager flew it, John Stack thought it up.


    • Maybe I’m old, but I remember Germany actually flying supersonic airframes and with even more advanced control systems earlier in WWII. Mach 1 was obviously doable since it had already been accomplished; and routine.

  1. The center piece and my most treasured piece of memorabilia down in my aviation themed man cave is an AC Delco poster signed out to me personally by Chuck Yeager, Bob Cardenas (pilot of the B-29) and Bob Hoover (backup / chase) … the principals in that infamous flight. Next to it is a picture of my Skyhawk sitting on the Edwards AFB South base ramp next to the loading hole in the ground where the X-1 was lowered and subsequently raised into the B-29 mother ship. Putting it into juxtaposition, I wasn’t born until nine days after that flight and two of those people are still alive!

    Most people think that the X-1’s flights were all at Edwards AFB (then Muroc AAF). Not so. The first unpowered drop/glide test flights of the XS-1 (only later X-1) occurred at Pinecastle AAF, FL on January 25, 1946. Pinecastle AAF was renamed McCoy AFB in the 50’s and you all now know it as Orlando airport or MCO. Three X-1’s were built and 18 pilots flew the airplanes. All powered flight occurred at Muroc AAF, later renamed Muroc AFB when the USAF was established and then changed to Edwards AFB in honor of Capt. Glen Edwards who was killed in the crash of a YB-49 on 5 June 1948..

    Circa 1984 when I was NCOIC of one of the test forces at Edwards, I discovered that Chuck Yeager’s Son, Mike, worked for me so I asked him if he could get me something signed by his Dad. A few months later, the poster showed up but it took me almost 30 more years to get Gen Cardenas’ and Bob Hoover’s autographs on it. It will be donated to the new Edwards AFB Flight Test Museum when their new hangar is finished. I’ve named the poster, “The Men of Mach 1 – 14 October 1947.” Some may wonder why Mike got me an AC Delco poster … if you remember in the 1980’s, Chuck Yeager was a spokesman for AC Delco and was often seen standing in front of a Northrop F-20 Tigershark and sometimes next to a Corvette on TV commercials.

    Like you, some time in the 50’s I remember reading a book about the X-1 and Edwards AFB. I thought that surely Edwards must be some magical place in California and vowed to some day visit the place. Little did I know that in just 12 years time, I’d be assigned there and wind up spending 15 1/2 years to the day of my USAF career working all manner of flight test programs. In fact, I restored an Aeronca 11BC Chief in the very hangar where the X-1 had been housed during the time. Wonderful aviation memories.

    I’d urge anyone interested in such things to visit the Edwards AFB Flight Test Museum (when the new building is finished) as well as the NASA Armstrong (formerly Dryden) Museum, as well. I hear that sometimes Base tours can be arranged, as well.

    I wonder where that hidden broom handle Chuck used to close the canopy went?

  2. “Sometime in 1978, I was thumbing through an issue of Esquire magazine…..”

    EUREKA! I’VE FOUND IT! Finally, SOMEONE that ACTUALLY READ “men’s magazines” PURELY FOR THE ARTICLES! (laugh) The article obviously had a big effect on your career!

    No critique of a Bertorelli article would be complete without an obscure historical reference. I would say that Paul’s owning up to the source of his interest in aviation means that Diogenes has finally found his man! (laugh)

    Thanks for sharing!

  3. I read ‘Chasing the Demon’ (find it on Amazon) recently. It suggests, with some plausibility, that the sonic boom produced by the X-1 that day was second one of the day, but the XP-86 test team had been ordered not to say anything about it to avoid embarrassing the air force… and it wasn’t the first time they had done it either.
    We may never know for sure.

  4. Aviation geeks need more! Is there a simple history of how NACA designers worked out ways of keeping lift in the transsonic regime, and keeping airflow attached to the control surfaces to overcome Mach tuck (the “P38 problem”). The curve you show suggests that the only answer was to hustle on up to Mach 2, which wasn’t possible for many more years.

    • Scott – a while back NASA had an ebook available titled “Probing the sky : selected NACA/NASA research airplanes and their contributions to flight” which has a simplified overview of a number of X-plane programs including the preliminary steps to the X-1 and follow-on Mach 2 Douglas D-558-2. Excellent details but not as comprehensive as the NACA reports on the test programs – in other words, “simple, by comparison” – 600 pages worth, though much of the content covers later programs. As an aviation geek, I couldn’t stop scrolling.

      • Thanks for the information. A Google search shows the this ebook is still available. A great download.

  5. I had the honor to spend some time on the phone with Chalmers “Slick” Goodlin, shortly before he died in 2005. I was a bit stunned by the acrimony he presented relative to his portrayal in the movie “The Right Stuff.” He was affable and easy to talk with about his role with the X-1 program.

  6. As a teenager during the ’50’s and totally devoted to model airplanes at the time (forget school and their exciting studies of things like Macbeth), I was enthralled with the news of someone actually breaking the “sound barrier”. The whole concept confused me though, for I knew that things like bullets regularly exceeded the speed of sound every day. For airplanes, we soon learned that once the ship had passed through this “TRANSONIC” region, once again things became calm and now the major worry turned to aerodynamic heating. How the heck was all this possible? And what was happening during this mysterious “transonic” region of flight.
    Toward the end of WWII, new P-38 fighters were having serious problems pulling out of a dive, leading to many a pilots demise. Discussion of things like CONTROL REVERSAL captivated me, for I did not yet understand this mystery at all.
    Unfortunately, there was no internet or easily available information source to help satisfy my curiosity other than our local library’s Encyclopedia Britannica. I had to be content with the knowledge that that these books contained or scour the library “card catalog” for other books and information that usually ended up in frustration.
    MANY years later, I learned that not all PARTS of the airplane pass through the air at the same speed; hence much difficulties are experienced when flying CLOSE to the speed of sound.
    Because of curvature differences, an airplane flying below but close to the speed of sound can be subjected to extreme buffeting. Below Mach 1 airflow tends to speed up and follow the curved surfaces often exceeding the speed of sound and with flow separation; while airflow at other parts of the airplane with less curvature, airflow is happily still below the speed of sound.
    While it took me forever to learn this relatively simple concept, I credit these past exciting times for instilling in me a thing that I value so much even today: MY CURIOSITY!
    Jerry King

  7. You don’t have to be called Paul to write brilliant articles for AVweb, but…actually, maybe you do, whether it’s Bertorelli or Berge 🙂

  8. Paul – You still have your second grade report card? Freud would have something to say about that ;>)

    Everyone should read Yeager’s book. He talks about Stack and gives him lots of credit for the program.
    Fascinating read and really shows how truly talented he was and still is during so much of our aviation history.

  9. Thanks, Cameron G. — thanks to Kindle I quickly found “Chasing the Demon” which heavily demystifies Bob Hoover and Chuck Yeager, maybe too heavily but in order to give a fair share of the credit to the other 8 or 9 precursors, especially “Slick” Goodlin. “Demon”‘s portrayal of Yeager makes sense when compared with the descriptions I have read of his contributions to the Challenger hearings, where he coached Richard Feynman to a effective demonstration of the temperature sensitivity of the elastic properties of rubber rocket seals, performed with a glass of ice water. Now I’m off to download the NACA summaries.