By DARYL MURPHY
Ten years after the end of World War I, the American public had become enchanted with the romance and excitement of the noisy, speeding machines that locked in aerial battle around racing pylons. The government, however, was more realistic; they saw little urgency to develop aviation rapidly during the idyllic postwar years. Military aviation branches had made design strides; their airplanes had won all eight Pulitzer Trophy races and two successive Schneider Trophy events, but by the late 20s, the designs were becoming counter-evolutionary. Their one-off racers were biplanes powered by the two or three available liquid-cooled V-12s of about 400 horsepower, and could fly as fast as 250 mph, but most of the first-line pursuits still operated in the 150-170 mph range.
In the commercial market, aircraft producers were struggling. Their biggest sales competition was the thousands of surplus trainers which had flooded the market in 1919, and about the only affordable powerplants on the market were leftover OX-5 and Hispano-Suiza V-8s. Not too many cash-strapped operators were willing to pay for the progress engine designers were likely to be offering. Between 1921 and 1928, while military pilots were going twice the speed they had previously, the civilian closed-course speed record had risen a paltry 43 mph. It wasn’t until racing began to get organized into national events that civil aircraft designers were moved by the prospect of fame and its accompanying fortune.
Dozens of smaller prizes were offered to air racers based on engine or weight formulas, but it would always be the big-bore, unlimited free-for-all speed dashes which got the major money and all the ink in the newspapers. Civil manufacturers didn’t have the resources to compete with Government and its expensive equipment. Then something happened which spurred the worldwide development of the next generation of aircraft: the mid-Twenties introduction of the Wright Whirlwind and Pratt & Whitney Wasp, the first relatively high-power and reliable powerplants. Suddenly, designers had access to guaranteed horsepower right out of the crate. It had its price, but it was available to one and all. With a little creative tuning, innovative racers could compete at the same power levels as their Army and Navy counterparts.
At the Travel Air plant in Wichita, chief engineer Herb Rawdon and his assistant, Walter Burnham, were among the first to take advantage of the military’s lethargy. They knew that high speed was not solely dependent upon horsepower, although that’s how the military kept winning the big races. If it looked like some upstart racer could be a little faster than an Army or Navy racer, the service would just install a bigger engine or soup up the one it had.
The two had been mentally designing a racer in their spare time, but its actual construction was more happenstance than the product of deliberate planning. In Wichita in springtime, the inspiration to go racing was as regular as iris blooms. Dozens of aircraft companies were located there, and inevitably, owners and engineers suddenly realized that it would be only a month or two before the air racing season began, and they weren’t ready with their latest model. Travel Air boss Walter Beech, whose company was the world’s largest producer of both monoplanes and biplanes in the late Twenties, knew that his company’s success at racing was one sure method of making even more sales.
Every year about mid-April, Beech would saunter into engineering and ask just what was planned for him in the way of equipment for the season. Other projects would be put aside as everyone concentrated on a high-priority project converting a stock airplane to a racer. Deadlines were usually met, but more than once an airplane’s paint was wind-dried enroute to the opening event.
“All things being equal,” Rawdon remembered saying to himself after the 1928 Nationals, “I’d just as soon not go through this exercise next year.” He decided to get his ideas down on paper and be ready when Beech got his annual itch.
The biplane-monoplane controversy had not yet been resolved in 1928, but it looked like the two-wing faction–which was headed by the military–was winning. Monoplanes all over the country had been flat-spinning their way to the ground. Nonetheless, Rawdon decided on a wire-braced monoplane design with fixed landing gear. He admitted that the 1928 Schneider Trophy racers had a strong influence on his decision. He figured the company would not finance the project, so decided that he and Burnham would partner it on a part-time basis, after hours, and in secret. They called it the Travel Air Model R–for racing, not for Rawdon.
A stress analysis was prepared based on existing CAA requirements, and a gross weight of 1,750 lb. was assumed. An as-yet-undetermined radial engine would power the airplane. The airplane had a buried cockpit, one which barely interrupted its sleek, straight fuselage, and its wheels were covered with large, graceful pants.
As expected, Beech materialized in Rawdon’s office late in the windy spring of 1929, and the engineer was ready. The idea of a special racing plane intrigued Beech.
“How soon can we have it in the air?” was his only question. Rawdon told him about ten weeks-which, not coincidentally, was the amount of time remaining until the 1929 National Air Races in Cleveland.
As it turned out, it was about as easy to construct two airplanes for the event as one. A local builder and promoter had indicated he would have a 275-300 hp straight six developed in time for the race, so Rawdon and Burnham built a second R to accommodate the inline engine.
Early in 1929, Wright had debuted their new R-975 (J-6-9 Whirlwind). The 300 horsepower engine was just what the Travel Air R needed (although the radial was soon persuaded to put out 420 hp), especially when tightly cowled in the newly developed NACA ring which added precious mph to the design.
The six-cylinder engine never materialized, but Gaston and Louis Chevrolet-the Indianapolis racing car builders who had earlier sold their passenger car operation to General Motors–contacted Travel Air with an inverted air-cooled six called the Chevrolair. Although its power rating was only 250 hp, it generated immediate interest for the second racer.
The fuselages were constructed of welded steel tubes, the wings were all-wood, and both were plywood-covered. Two sets of wings were built for the Wright-powered model-shorter, narrower-chord versions for closed course racing and a longer and wider pair for cross-country contests.
Beech, who was not yet a monoplane convert, also ordered one special Travel Air biplane powered by a J-6-7 Whirlwind fitted with NACA cowl to be built for the races.
The small group of people working on the R project were typically close-mouthed; they simply didn’t see any reason to talk about the racer, although it was literally being built behind closed doors–unusual at the time, especially during 100° Kansas summer days.
As more people tried to find out what was going on at Travel Air, the less they were inclined to talk. An air of mystery and developed, and then it turned to excitement and finally speculation. So, it was probably inevitable that Wichita Eagle and rival Beacon began dubbing the project the “Mystery Ship,” generating substantial amounts of advance national publicity. Walter Beech decided if he kept the secret a little longer, it might be worth a lot of newsprint.
Early in August, two weeks before the start of the Nationals, the number one racer, R614K, took to the air minus its streamlined cowl and wheel spats. Test pilot Clarence Clark reached 185 mph in full-throttle level flight. A few days later, with the NACA cowl installed, Clark got the surprise of his life when the same power and altitude produced 225 mph!
Walter Beech had lined up Atlanta Travel Air dealer and noted air racer Douglas Davis to fly R614K, while Clark would handle the Chevrolair-powered R613K. When the pair left for Cleveland, it was so late that the company artist had not even finished with the paint on Clark’s airplane. As Davis left Travel Air’s field, he decided to buzz the gathered spectators. Diving toward the small crowd at an indicated 275 mph, he misjudged slightly and actually hit the ground with the landing gear. A shaken Davis flew on to Kansas City, where he found he had broken a wheel, which he replaced.
When the two racers arrived on Sunday at Cleveland, they landed and taxied to the hangar Beech had arranged for, cut their engines and rolled inside. The doors were immediately closed and guards posted. The legend was born.
By the next morning, the newspapers were full of speculation about the airplane from Wichita, now being called the “Mystery S.” When the two racers finally rolled onto the turf for Monday’s competitions, the crowd went wild.
Throughout the week, the Rs dominated the spotlight. Davis won the Experimental Event, and then J.O. Donaldson climbed in it for the first time and won the Rim of Ohio Derby. All Clark could manage in the Chevrolair R was a third in a 510 cu. in. race after his engine overheated. The six-cylinder R was returned to Wichita on a truck. Its Chevrolet was later replaced with a Wright.
The final event of the 1929 Cleveland National Air Races was 50-mile sprint race-the initial Thompson Trophy event-expected to be a closely fought battle between Army Lt. R.G. Breene in a Wasp-powered Curtiss P-3A and Lt. Cmdr. J.J. Clark, flying a Navy Curtiss Hawk. Five civilian aircraft were entered in the free-for-all, but none was expected to have a chance against the military’s fastest pursuit planes.
As expected, Breen shot from the starting line into the lead, but as he rounded the scattering pylon, Davis whizzed past the Army flyer and jumped into the lead, pulling steadily away and picking off the slower aircraft one by one, putting them a lap down. But at the start of lap three, Davis cut inside a pylon. Under the rules, he had to go back and re-circle the marker or he would be disqualified. Realizing time was critical, Davis banked the R so sharply that he momentarily blacked out from the G forces. Regaining his awareness, he didn’t know if he had made a complete turn around the missed pylon, so he recircled it again. Back on the course, he upped his speed and incredibly went on to re-lap the entire field and finish more than 30 seconds ahead of Breene–and did it all in 14 minutes!. Roscoe Turner’s civilian Lockheed Vega was third, ahead of Clark’s Navy Hawk. On average, the civilians had thrashed the military.
Davis and the R614K had turned in an average speed of 194.9 mph–which included the time lost twice re-circling the missed pylon. It was more than 50 mph faster than any commercial aircraft had ever flown in a closed-circuit race.
Clarence Clark won two more races that summer in R614K, at Sioux Falls, S.D. and Tulsa, Oklahoma. In the fall, Doug Davis flew the R from New York to Atlanta in four and a half hours, establishing a record.
Four additional “Mystery” ships were built, flown by such luminaries as Frank Hawks, Jimmy Doolittle, and Florence “Pancho” Barnes. The last airplane was ordered by Italian dictator Benito Mussolini, presumably used to develop his country’s pursuit designs.
The triumph at Cleveland meant even more sales to Travel Air, which at the end of the year had been acquired by Curtiss-Wright Aeronautical Corp. But it also marked the beginning of a new era in aircraft design. Until that time, engineers had played a secondary role in creating aircraft, one of figuring out how to make the race pilot’s suggestions for improvement work. From now on, engineers would point the way.
Despite the monoplane win in 1929, the odds-on favorite in the first Thompson Trophy race at Chicago in 1930 was still a biplane, a highly modified Curtiss XF6C-6 Hawk fighter flown by Marine Captain Arthur Page. As expected, Page ran away from the field at the start, and began lapping back markers on the third lap. Then, as Page rounded the home pylon on his 17th lap, the Curtiss rolled over and plunged into the ground. Investigation later indicated that the pilot was overcome by carbon monoxide in the tight cockpit.
That let Speed Holman in the Laird Solution biplane win, and Jim Hazlip, flying the Shell Oil Travel Air R, a close second. Frank Hawks, in the Texaco No. 13 Travel Air R dropped out early with fuel feed problems. Hazlip’s Travel Air might have won, but Shell Oil didn’t want to use the leaded fuel blend, which was furnished by the Ethyl Corp. (owned by Shell competitor Standard Oil), so a lower-octane mixture of straight gasoline and slow-burning toluol was used. The fuel cost Hazlip about 100 rpm, and Holman won the 100-mile race by mere seconds.
The Mystery S may not have pulled off the repeat win, but it had made its presence known. In the 1930 race, the Curtiss had been the lone military entry, and the Laird was the last biplane to ever win the Thompson Trophy. It had started a revolution of development changes in aircraft, inspiring later American military pursuit designs; the triumphant Travel Air had helped end the American military’s reliance on biplanes and liquid-cooled engines.
And the sun had risen on the brief and brilliant Golden Age of Air Racing.
1929 Travel Air Model R (R614K) Specifications and Performance
||420 @ 2350 rpm
|Wing span, ft.
|Wing chord, in.
|Wing area, sq. ft.
|Gross weight, lb.
|Empty weight, lb.
|Wing loading, lb./sq. ft.
|Power loading, lb./hp
|Maximum speed, mph
|Cruise speed, mph @50% power
|Landing speed, mph
|Rate of climb, fpm @ sea level
|Service ceiling, ft.
Travel Air Engineers Herb Rawdon and Walter Burnham designed the Model R in anticipation of boss Walter Beech’s annual need for a racer.
Test pilot Clarence Clark reached 185 mph on an early test hop without its NACA speed ring. A few days later, with the cowl installed, the same power setting and altitude produced an astounding 225 mph.
Douglas Davis flew NR614K to a 194.9 mph victory in the first Thompson Trophy race, the first time a civil airplane had defeated military pursuit racers.
Shell acquired the third Model R; Jimmy Doolittle used it for an aerobatic routine during the 1930 Chicago National Air Races, and Jimmy Haizlip flew it to a win in the 1,000 cu. in. event and placed second in the Thompson Trophy.