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In the early 1960s I was one of the Roadrunners who worked on the world's most advanced aircraft, the A-12 Oxcart, barely 60 years after the Wright Brothers first flew. 2003 is a great year to celebrate the Wrights' achievement, because it's the Centennial of their first success. I was also interested in making comparisons of differences and similarities between the two "projects".
History
Prior to 1903, there had been no successful human flight in powered heavier-than-air craft. True, there had been hot-air and hydrogen-filled balloon flights fully 120 years before, by three Frenchmen, brothers Joseph and Jacques Montgolfier and Jacques Charles, both in 1783. But that was floating and not flying. Heavier-than-air flight was much longer in arriving.
Then, suddenly, two bicycle mechanics from Dayton, Ohio, performed that feat on a windy sand dune at Kitty Hawk, North Carolina on December 17, 1903. But it was not that sudden to them. They had spent at least 7 years in planning and building, but especially in learning about what it took to fly successfully. In the process they built the first wind tunnel dedicated to determining flight characteristics of wings, control surfaces, and propellers.
They studied materials in order to make the aeroplane (the Wrights' name for it) light and strong enough to succeed. They had to design and build their own lightweight engine as none were available to meet their specifications. They designed the first system of 3-axis control using wing warping and a rudder and elevator, and flight-tested it on an unpowered glider in 1902. In short, the Wrights were the first aeronautical researchers, engineers, builders and ultimately pilots to be successful.
They were inspired by a few others, mainly Otto Lilienthal, a German glider experimenter killed in a gliding accident in 1896, and Octave Chanute, an engineer in Illinois who had written about the history of aeronautics to date, which wasn't much, but Chanute corresponded with the Wrights and gave them encouragement..
Half a century later, in the mid-1950s, Kelly Johnson led Lockheed Advanced Development Programs (ADP) group, affectionately known as the "Skunk Works" by the workers. This group developed the high-altitude U-2 aircraft, and versions of it are still flying today. Shortly thereafter, the "Skunk Works" began development of what was dubbed the A-12 Oxcart, the high-speed successor to the U-2. The A-12 first flew in 1962, and soon attained top cruise speeds over 2000 mph. These "black" birds (A-12 and U-2) and their derivatives are what we Roadrunners currently celebrate in our semi-annual Reunions.
Differences (1903 to 1963)
The Wright Flyer averaged 31 mph at an altitude of a few feet above the sand. The A-12 flew about 67 times faster (2100 mph) and a lot higher (80,000+ ft) than the Wright Flyer did. As to range, the longest flight on that windy day in North Carolina was about 800 feet.
The design range for the A-12 was over 2000 miles. As to gross weight, the Wright Flyer was less than 1% as heavy as the A-12 (600 lbs vs. 100,000+ lbs).
The Wright Flyer was mostly wood and fabric, while the A-12 was made up mainly of titanium. The "First Engine" was designed for 16 Horsepower (delivering roughly 100 lbs of thrust per propeller), while the twin J-58s on the A-12 developed a total of over 60,000 lbs with afterburner at takeoff (although much less at cruise, where a unique inlet/engine combination was needed to produce enough thrust in the thin air at 80,000+ ft.).
At Mach 3+, the 'stagnation temperature' from aerodynamic heating on the A-12 rose to 800 degrees F on the leading edges. The temperature rise on the Wright Flyer at full speed (31 mph) was a fraction of One Degree F. No titanium needed here! The Wright Brothers had almost no instrumentation, whereas the A-12 took advantage of advanced electrical/electronic technology, including the first usage of advanced solid state devices such as transistors in computers for measuring and controlling most of the aircraft's systems.
What did the well-dressed pilot wear in 1903? A business suit. Of course, in 1963 the A-12 pilot was required to don a full-pressure suit to counter the risk of de-pressurization at high altitude, where without such protection the pilot's blood would boil at normal body temperature.
Similarities (Comparing the two historic "Projects")
Both the 1903 Flyer and the A-12 were set up for minimum static stability in order to minimize drag. This made both of them very tough to fly, as evidenced by difficulty on their first launch.
Roadrunners know that the unofficial first flight of the A-12 was an inadvertent lift-off during a high-speed taxi test, when pilot Lou Schalk reported that the aircraft was very unstable and he barely managed to wrestle it safely back onto the ground. Later, in the A-12's "official" first flight, the 3-axis Stability Augmentation System (SAS) was turned on and provided the needed stabililization, making the aircraft very manageable.
But the Wright Brothers had no such help from modern electronics, and the 'unofficial' first flight for them was actually on December 14, 1903, when Wilbur Wright made a hard landing after only 3 seconds.
However, it was long enough for him to learn that the pitch axis was very unstable and needed a lot of attention to maintain control. Three days later, the result was four successful flights.
Secrecy was another connection between the two projects. The Wright Brothers were worried about other experimenters stealing the results of their hard work, and rightly so! So they kept the details secret, even when they were flying on an open farm field in Ohio for long periods.
This was helped by the fact that few reporters were interested, doubting that the Wrights actually flew! Secrecy on the A-12 was a matter of life and death, keeping the enemy from developing a defense against a capability that we wanted them to doubt even existed! Not just the details of the design performance but also the actual flying location were secrets. Most important, both the Wright Flyer and Lockheed A-12 were built by very small groups of people, with a small budget, and working to solve tough problems never understood before. The bicycle shop in Dayton and the desolate sand dune at Kitty Hawk in 1903 demands that we see the similarity to the small factory at Burbank and the secret desert test site in 1963.
Noteworthy Current Event
An exact replica of the Wright Flyer has been built and is planned for flight at Kitty Hawk on December 17 of the 100th Anniversary Year.
Takeoff is set for 10:35am, 100 years to the minute from the actual first flight. The sponsors are the Experimental Aircraft Association (EAA in Oshkosh, Wisconsin) and The Ford Motor Company, among others. An attempt has been made to match every detail of materials and construction from the 1903 Aeroplane, including the engine. The reader has one guess as to what is the pilot's chief concern. No, it's not that age-old question: "Will it fly?".
The main worry is that when flying it will be too difficult to control due to its natural instability!
Summary
Both the Wright Brothers and the Roadrunners were having to stretch the known fields of aeronautics in every way; in materials, in control and in motive power. But Wilbur and Orville had no real successful inventors to look back and up to, while we were living in a world they had created, with propeller-driven and jet planes and even rocket planes soaring to very high speeds and altitudes.
The Roadrunners stood on their shoulders and that is why we honor them on this 100th Anniversary of the First Flight. As should any of the millions of people who have had a career in aviation, or indeed those hundreds of millions who have been passengers or cargo customers on the modern aircraft spanning the globe today.
In a very real sense, Wilbur and Orville Wright created the prototype for Kelly Johnson's "Skunk Works". We couldn't have done it without them!!
2003 James R. Walborn
Honeywell Engineer-Retired
(Had 6 years on A-12, MD-21, YF-12, About half of it at the Area)
With Credit to my wife Mary Ann Walborn and Jerry Miller, friend and Roadrunner, for proofreading and improvements For wonderful details on the 1903 events, see The Wright Brothers, by Fred C. Kelly, a paperback biography.
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