HOW SUPERSONIC FLIGHT CAME TO BE

Today, the first commercial flight to the edge of space has happened. What will come from that is as unknowable as everyday supersonic flight was to the Wright Brothers when they created the first controllable heaver-than-air flying machine.

The flight reminded me of another day in the desert 68 years ago, and the industrial revolution it took to get to that morning.

From my coming book (next May) - “Downtown: The US Air Force in Southeast Asia - 1961-75":

A clear spring dawn over the California high desert is always spectacular, as the sun rises out of the Sonoran Desert to the east and the deep clear blue of the sky becomes progressively more visible. So it must have been on the morning of May 25, 1953, when two pilots approached the aircraft they were to fly that morning, parked on the ramp at the Air Force Flight Test Center, otherwise known as Edwards AFB.

The smaller of the two airplanes was well-known - a North American F-86D Sabre. The hulking monster sitting next to it, also a product of North American Aviation, made the Sabre look small when its aluminum skin glittered in the early dawn light. As they approached their airplanes, North American Chief Test Pilot George Welch turned to his “chase” pilot, AFFTC Commander LCOL Frank K. “Pete” Everest, and bet him two beers that they’d “do it” that morning, on the new airplane’s first flight.

Everest strapped into his Sabre as he watched Welch - the man who had shot down four Japanese aircraft over Pearl Harbor on December 7, 1941 - climb into the monster.

At the end of the runway, the two jets pulled out onto the long dry lake - the longest, widest runway in North America - and accelerated. Everest became the first human to see the gout of flame with the diamond shock waves spout from the exhaust of Welch’s airplane as he hit the afterburner and soared into the desert sky, climbing like the proverbial homesick angel and leaving Everest far behind in his Sabre, even using full afterburner.

Twenty minutes later, Everest had finally caught up with his charge and the two airplanes were high in the sunlit sky over Edwards at 35,000 feet. Everest was using afterburner just to keep station with the big arrow-shaped fighter at his 10 o’clock low.

“Hang on, here we go.” Welch’s voice echoed in Everest’s headset.

And then the gout of flame with the diamond-shaped shockwaves erupted again from the exhaust as the engine went from 9,870 pounds of thrust to 14,000 pounds in 20 seconds with a “whoomp!” so loud Everest could hear it through his canopy and helmet. In less than a minute, the big silver airplane was out of sight in the deep blue sky.

On the ground, the North American project engineers - and everyone else on base - heard the echoing explosion of a sonic boom from 7 miles overhead.

George Welch didn’t have to dive his jet this time to go supersonic. He did it in level flight. The airplane he did it in was the North American YF-100. That afternoon, just to prove it wasn’t a fluke, he did it again. Operational supersonic jet-powered flight had arrived and aviation would never be the same.

As to what it took to get to that morning, the following is from my coming book, “The Tonkin Gulf Yacht Club: Naval Aviation in the Vietnam War”:

The supersonic aeronautical revolution began in the years immediately before the outbreak of the Korean War, an event that would speed the revolution’s advance. North American Aviation first began thinking about making a supersonic fighter in 1948. At that time, there were two ways to go: a very big fighter powered by a very big engine, or Something Else, only dimly seen at the time. Edgar Schmued and Raymond Rice, the premiere fighter designers in the United States at the time, were aesthetically offended by the idea of a big airplane that was unable to match what the P-51 and the F-86 could do.

The key to whatever the design would be was the engine. By June 1948, it had been determined that the optimum sweepback was 45 degrees, and the project became known within North American as the “Sabre-45.” Had the project proceeded then, it would have probably been powered by the big General Electric J53, which later provided 23,000 pounds of thrust with afterburner. At the time, North American believed the best alternative light engine would be the afterburning J-40; this Navy-developed design ultimately became one of the major disappointments of early jet engine development. Everything changed in early 1949, when Pratt and Whitney let them know about the JT3, the engine that would prove to be the most significant gas turbine engine since Whittle’s W1.

The JT3 was a turbojet development of what had begun life as the PT4 turboprop, the planned powerplant for the first design of the B-52. In its developed form as the J57, it would power the F-100, the F8U Crusader, and the F4D Skyray, as well as the Boeing 707 and Douglas DC-8 jetliners. It was light, yet as strong as anything ever made by Pratt and Whitney; its reliability record would be second to none. North American formally proposed a supersonic fighter powered by the JT3 in January 1949. The Air Force gave quick approval and the program became official on February 3, 1949, though it was still essentially company-funded

The F-100 was the first beneficiary of a mobilization between industry and government that provided more financial support for more basic aerodynamic research and advanced machine tool development than had been spent in the 50 years since the Wright Brothers first flew, in the quest to create operational supersonic flight. Such an effort was only possible in the country which in 1950 produced 52 percent of the planetary Gross Economic Product while at the same time taking the German autobahns to their penultimate development in the Interstate Highway System while also creating the modern American middle class through the G.I. Bill.

In April, 1949, North American used company funds to build the first supersonic wind tunnel. A development based on the German Kochel system (Edgar Schmued, who was conversant with all pre-war German aerodynamic research, and who didn’t have to wait for translations of what the company found in Germany in 1945, has to qualify as the single most cost-effective aircraft designer in history), the tunnel had a sphere of dry air exhausting through the working section into a vacuum chamber, with a peak attainable Mach number of 5.25. The result of these wind tunnel tests was a radical redesign of the initial idea, with the very fortunate result that the horizontal stabilizer was pulled off the vertical fin and put low on the fuselage, where it belongs on a supersonic airplane. At the same time, Pratt and Whitney developed the variable nozzle for an afterburner. The result was a reliable engine with an afterburner that never failed to ignite.

It would have been impossible to develop the Super Sabre and the following supersonic aircraft developed by both the Air Force and Navy without the creation of the industrial wherewithal to build supersonic airplanes. Creating what came to be known as “The Century Series,” as well as the Navy’s Crusader and Phantom II, was only possible with major advances in structures, materials and techniques, propulsion, systems, and aerodynamics that eclipsed everything that had gone before. The bill for aerodynamic research, which included the cost of the X-1 series, the X-2, X-3 and D-558-2 Skyrocket was $375 million, while the cost of engine research and development was $280 million, all in 1950s dollars.

The Air Force spent $397 million between 1950-54 on a program to create heavy presses capable of squeezing large light-alloy forgings which would have been otherwise sculptured from a solid slab by “hogging” or constructed from many separate parts The result of this was the industrial ability to pop out lightweight single-piece aircraft skins in minutes. Radical new machine tools that could remove vast amounts of metal at high speed with extreme precision were created at a cost of $180 million. Automatic precision machinery capable of drilling, countersinking, dimpling, riveting, reaming, bolting and sealing, and doing all these operations in sequence, was created - all before computers. A brand-new industry capable of creating 500-600 tons of wrought titanium a month was created; it was the metal that made supersonic fighters possible. Further hundreds of millions were spent on developing electrical and hydraulic systems able to operate reliably after soaking in temperatures up to 300 degrees Celsius. This in addition to a range of reliable miniaturized electronic devices that still used fragile vacuum tubes, since this was before the transistor revolution.

Between 1950-55, the United States spent over $5 trillion in 2019 dollars, just to acquire the industrial capability to produce supersonic fighters. When the cost of aeronautical research is added in, the creation of supersonic flight cost approximately another $4 trillion. This industrial mobilization was only exceeded in cost by the Manhattan Project. While the F-100 did not use all this infrastructure, it paved the way for all others.

Presented for your consideration.

(Should you be interested, you can pre-order “The Tonkin Gulf Yacht Club” here: https://www.amazon.com/Tonkin-Gulf-Yacht-Club-Aviation-ebook/dp/B08W572RQV/ref=sr_1_6?crid=FAAC6HMBD5G5&dchild=1&keywords=thomas+mckelvey+cleaver&qid=1626020557&s=books&sprefix=thomas+mckelvey+%2Caps%2C349&sr=1-6)

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