Anyone who has ever attended an air show has witnessed the death-defying acrobatics of pilots. But one maneuver stands out as a crowd favorite: the “barrel roll,” in which an aircraft makes a full 360-degree rotation in mid-air.
It should come as no surprise that performing this exercise is no easy feat – even in a small stunt plane or fighter jet – and requires an experienced pilot to perform it. But is it possible to make a barrel roll in something larger, like a commercial airplane?
Richard P Anderson – a pilot, professor of aerospace engineering and director of the Eagle Flight Research Center at Embry-Riddle Aeronautical University in Florida – said yes, and even knows people who have proof that they do.
“I only know people with video tapes [doing barrel rolls],” Anderson told LiveScience.
Perhaps the most famous pilot to ever do this in a commercial aircraft was Alvin Melvin “Tex” Johnston, a test pilot for Boeing. In the summer of 1955, Johnston took a four-engine Boeing 367-80 (also known as the Dash 80) for a spin – literally.
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To impress Boeing executives watching from a yacht on Lake Washington near Seattle, the maverick pilot performed two barrel rolls along with a chandelle, a stunt in which a pilot combines a 180-degree turn with a climb, according to the Los Angeles Times. That Monday, Johnston’s boss called him into his office and asked him what he was doing. Johnston reportedly responded, “Selling planes,” thus Airplane and pilot magazine.
So how did he successfully perform a barrel roll in such a large aircraft? Anderson said the size of the plane doesn’t matter as much as the pilot’s ability to moderate the amount of g-forces placed on the plane during the roll.
“The physics are the same regardless of the size of the aircraft,” Anderson said. “In a barrel roll, the pilot tries to keep the g-load of the aircraft close to 1 g. In other words, pretty close to what we feel here on Earth.”
To complete the maneuver, the pilot must perform the roll while also holding the nose of the aircraft up and then dropping the nose down – all while the aircraft is flying at cruising speed, which is approximately 885 to 965 km/h ( 550 to 600 mph). , as if floating through a barrel, thus Flying magazine.
“The only real limiting thing about doing a barrel roll is how fast the airplane rolls,” Anderson said. “In a barrel roll, you pull the nose up, and as you do the roll you let the nose fall, which allows you to maintain this low-stress environment. As the nose falls as you roll, you have what you have what to do is being able to roll the plane all the way around before the nose points too far down.
David Haglund, an experienced pilot in the U.S. Air Force and lecturer at The Museum of Flight near Seattle, added that the amount of airspace available to complete the role is also important, especially in a large aircraft versus a small one. Cessna.
“Before performing this maneuver, a pilot would consider the available airspace,” Haglund told LiveScience in an email. ‘In an airplane, a barrel roll would require a block of 600 meters in height [600 meters] above and below level flight altitude (total 4,000 feet) [12,000 m] to stay on the safe side.”
But while it is physically possible, some manufacturers have built a limitation into large, modern aircraft, perhaps to prevent future Tex Johnstons from performing similar aerobatic feats, especially with passengers on board.
“The Airbus does not give the pilot the ability to roll beyond 60 degrees without disabling part of the automatic flight system that controls the aircraft’s flight range,” said Haglund, who has experience flying A330 and A350 models.