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Hispanic Heritage Month—Breaking Barriers 75 Years Ago

  • Published
  • By Kevin Rusnack, Chief Historian / Robert Marcell, Historian
  • Air Force Life Cycle Management Center
Seventy-five years ago, USAF Capt. Chuck Yeager “broke the sound barrier” in the Bell X-1. His rocket-powered airplane was carried to altitude and dropped for its historic flight by a modified B-29 bomber flown by Mexican-American pilot Maj. Bob Cardenas.
Robert Leon Cardenas, Jr., was born in Merida, Yucatan, Mexico, in 1920. His family moved to San Diego when he was 5, and he became a naturalized US citizen in 1936. His aptitude for math and physics led him to enroll in San Diego State University for two years of pre-engineering, earning a full scholarship offer to Cal Tech. However, his decision to join the California National Guard derailed those plans when he was ordered to the Philippines in 1939. Then-Pvt. Cardenas’ education fortunately rerouted him first to aviation training and then to the US Army Air Corps (USAAC) in 1941. His first operational assignment was in the new field of troop-carrying gliders. The German Luftwaffe had successfully employed these in the early days of World War II as an alternative to paratroopers, spurring a hasty development program in the US.
After setting up a glider pilot training school in California, Cardenas was sent to the Army’s Materiel Division at Wright Field, home to the USAAC’s aircraft program offices, as well as the flight test organization. Cardenas was assigned to glider flight testing at the nearby Clinton County Airport in Wilmington, Ohio. This was dangerous work, considering the novelty of the designs and inexperience of the designers, with frequent crashes.
Captain Cardenas flew 16 different types of gliders and was promoted to head of that Flight Test Unit. His fortunes changed in in late 1943 when he received orders to go overseas. In January 1944, he made his first bombing mission from England as a B-24 Liberator pilot with the 506th Bomb Group.
On his 18th mission just two months later, he commanded a group raid over a German munitions factory. Flak repeatedly hit his plane wrecking its engines and wounding most of the crew. Cardenas took shrapnel to the head. The flight crew was able to stabilize their plane enough for all of them to bail out safely. Cardenas landed on the shores of Lake Constance that divided Germany from neutral Switzerland. He quickly surmised he was on the wrong side and attempted to swim across but was picked up by a Swiss fisherman who turned him into local authorities. Per policy, they interned him, then put him to work ferrying the many salvaged American bombers that had landed in Switzerland. After a few months, Swiss and French partisans helped him escape to France after D-Day, and he ended up back home by November 1944.
Repatriated and recovered, Capt Cardenas went to B-24 instructors’ school in Tennessee before being reassigned back to Wright Field in mid-1945 to attend its new, formal Experimental Flight Test School, the forerunner of the USAF Test Pilot School at Edwards Air Force Base (EAFB). He flew a variety of trainers, fighters, and bombers and took the specialized stability and control course. When the first American jets, the XP-59 and XB-45, arrived at Wright Field, he was among the first to fly them. Cardenas also had the chance to fly some of the captured German aircraft sent to Wright Field, including the Me-262, the world’s first operational jet.
The increasing size of new aircraft led to the removal of most flight testing from Dayton to Muroc Army Airfield (now Edwards AFB) in California after WWII. As a result, Cardenas and his fellow test pilots were organizationally assigned to Wright Field but conducted most of their tests during long deployments to Muroc, until finally moving almost entirely by 1951.
Major Cardenas became chief of the Bombers Test section at Wright Field. His first brush with fame came in July 1947 when he was picked as the carrier aircraft pilot for the new, secret “Experimental Sonic 1” (XS-1, later X-1) project to push past the speed of sound.
To keep the test aircraft simple and light, it was not equipped to take off under its own power but was instead carried aloft tucked partially inside the bomb bay of a B-29 and was air-dropped. Cardenas’ colleague Capt. Chuck Yeager was assigned to fly the X-1 itself. More senior in rank Cardenas was assigned as the officer-in-charge of the group of Wright Field pilots and engineers sent to Muroc for the XS-1 tests.
On October 14, 1947, following weeks of preliminary test flights, the time had come to push through Mach 1. With the X-1 loaded Cardenas brought his B-29 to 20,000 feet and 250 mph. Perhaps showing some nerves, he radioed to Yeager an erratic count-down to release: “10--9--8--7--6--5--3--2--1--Drop,” having skipped “4,” though no one seemed to notice. The X-1 dropped until Yeager ignited his rockets and quickly blew past Cardenas and into history as the first human to officially exceed the speed of sound.
Bob Cardenas’ career as a test pilot continued into the 1950s, most notably as the Chief Test Pilot for the Northrop YB-49—the jet-powered version of the “Flying Wing” and predecessor to the modern B-2 and B-21. He conducted the dangerous early stability and controls tests himself. During one such test, Cardenas deliberately stalled the aircraft (pulling the nose up so that the wings stopped producing lift) and was shocked to find that it flipped over backwards and entered a spin. He was able to recover and considered himself lucky to be alive. He reported that no further intentional stalls should be conducted.

Unfortunately, while Cardenas briefly left the program, test pilot Glen Edwards again stalled the YB-49 and flipped it but was not able to recover before it crashed into the desert floor of the base that thereafter bore his name. Cardenas immediately returned to finish the test program, notably flying it past the U.S. Capitol Building at the request of President Truman. The program was cancelled in 1950.
After 1955, Cardenas went into the operational world, commanding several fighter units, including a combat tour in Vietnam. Notably, he also commanded the USAF Special Operations Force at Eglin AFB and was Vice Commander of the Sixteenth Air Force.
He retired in 1973 as Brigadier General and died on his 102nd birthday this past March.