On September 15, spectators at the 51st National Championship Air Race in Reno, Nevada witnessed a gut-wrenching photo finish. But their thrills were outclassed by the tension Steve Hinton Jr. endured in the cockpit as he went head to head with Bill “Tiger” Destefani, his former mentor. Thousands came to their feet and roared as two of air racing’s fastest, most highly-modified P-51 Mustangs screamed past the home pylon at 500 mph in the closest race at Reno in more than two decades. As the pilots pulled their racers skyward, up and off the race course, neither was sure who had won. Below, the thousands in the stands continued their howled excitement.

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It was one of the most dramatic moments in more than a century of air racing, which was first organized in 1909 in Rheims, France. As aviation has evolved, so has air racing. Point-to-point cross-country races were staged in Los Angeles and Belmont Park, Long Island in 1910, and in Europe at events like the much-ballyhooed Schneider Cup seaplane races in 1913.

WWI halted the rise, but U.S. air racing blossomed in the 1920s with the advent of the Pulitzer Trophy Race, established by newspaper magnate Ralph Pulitzer, in which nearly 40 pilots, mostly military, flew military and ex-military aircraft through four laps of a 29-mile course. Like pre-WWI air racing, competitions like the Pulitzer Trophy were proving grounds for cutting-edge aviation technology and ace pilots.

By the 1930s, the “golden age of air racing” dawned at the National Air Races in Cleveland, Ohio. Advanced civilian machines performed alongside American military craft; race pilots were among America’s popular heroes, cheered by the hundreds of thousands who attended the National Air Races annually. WWII would again suspend air racing, but the sport resumed in Cleveland in 1946 with pylon and cross-country racing. Classes included the Goodyear “Midgets” (the forerunner of today’s Formula One class), AT-6s (ex-WWII trainers), Jets and what would become today’s Unlimited-class (the propeller-driven fighter aircraft that won WWII).

Then, in 1949, pilot Bill Odom lost control of his P-51 Beguine during the headlining Thompson Trophy race. He crashed into a house near the race course, killing himself, a mother and an infant. The tragedy shut down the National Air Races and halted multi-class pylon air racing for the next 15 years.

It’s the Indy 500 in the sky, with two major differences: Passing is only allowed to the outside of another aircraft, and when your engine blows you don’t simply coast to a stop — you still have to get your aircraft back on the ground.

Hall of Fame hydroplane powerboat racing champion Bill Stead resurrected air racing with the National Championship Air Races (NCAR). Launched just outside of Reno in 1964, NCAR remains the only major air race in the world, battling a decades-long decline in private aviation worldwide amid rising costs, security concerns, an increasingly risk-averse culture and a sea of competing public interests.

Six classes of racing aircraft compete at the NCAR — Unlimited, Jet, Sport, T-6, Formula One and Biplane — broken into Gold, Silver and Bronze performance categories. Like in auto racing, the pecking order is determined initially by qualifying: Gold, Silver and Bronze heat races determine the contenders for the final or Gold championship races in each class over five days. Racers who aren’t among the top qualifiers can climb to the championship finals through the Bronze and Silver heat races.

Races are conducted around an oval race course marked by 50-foot tall pylons, varying in length depending on the racers’ top speeds in each class. Aircraft fly counterclockwise and must stay to the right of each pylon; failure to do so results in a pylon “cut” and time penalty. It’s the Indy 500 in the sky, with two major differences: Passing is only allowed to the outside of another aircraft, and when your engine blows you don’t simply coast to a stop — you still have to get your aircraft back on the ground. In addition, pilots must fly in an FAA-mandated box: Minimum altitude on the race course is 50 feet above ground, while maximum altitude is 250 feet. Pilots must also stay within the lateral boundaries, or “showlines”, of the course.

The rules for racing are tighter now than ever. In 2011, racer Jimmy Leeward crashed after a structural failure in his Mustang just in front of the crowd at Reno, killing him and 10 spectators — the only such crash in NCAR’s history. In response, the FAA created more restrictive confines for the course to minimize debris in the event of a crash. The new rules were controversial with racers, particularly those in the Unlimited class, who recognized the difficulties narrower corridors would create in terms of passing and avoiding prop-wash (turbulence) from other aircraft.

It was in this contested climate of new rules and testy pilots that Hinton Jr. and Destefani faced off in the semifinal of this year’s competition. Destefani, a beloved veteran of air racing, was one of Hinton Jr.’s mentors; when Destefani took a break from the sport in 2008, Hinton Jr. took his spot on Team Strega, becoming the youngest ever NCAR champion in 2009 at age 22. After six years off, Destefani returned this year with something to prove: he could still compete, and win.

Destefani started the race at the back of the pack after taking it easy during qualifying to familiarize himself with the new 8.085-mile Unlimited course. To win and earn the all-important pole position for the Sunday final, he would need to pass the five competitors ahead of him. As the race’s pace plane pulled away, Destefani pushed his throttle all the way forward, extracting nearly 4,000 horsepower from his modified Merlin V12 (which is roughly three as powerful as a WWII-era P-51), accelerating to over 500 mph.

By the beginning of lap two, Destefani had overtaken all but Voodoo — Hinton Jr.’s P-51. Trailing a torrent of water-methanol coolant, the master chased his pupil down over four laps, pulling 4 to 6 Gs in every corner. They crossed the line neck and neck; minutes later, Hinton Jr. was given the win after review of timing and video footage.

Seconds later, climbing for altitude, Destefani declared a mayday. With his engine on the verge of meltdown, he skillfully bought his racer to earth. This was high drama in the high desert — but it wasn’t over. Moments after the race, word came that Destefani had been disqualified for exceeding the FAA’s maximum altitude for the course. It was a crushing blow for both his team and fans. With his main adversary eliminated from competition, Hinton Jr. went on to dominate the Unlimited final, defending his place on top of the world’s fastest motorsport. As for Destefani: he re-announced his retirement after the race.

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