“Barrel” — one of the most famous aerobatic maneuvers, the essence of which is to rotate the aircraft around its longitudinal axis by 360 degrees. If you have ever attended an air show, then you have probably seen this stunt performed. The “barrel” can be single or multiple, that is, the plane can make one or several revolutions around its axis. This figure was first shown by the American pilot Daniel Maloney back in 1905. However, performing «barrel» is a challenging task even for sport aircraft pilots and requires a lot of experience. But can this same trick be performed on a large airliner?
«Barrel» implies the rotation of the aircraft around its longitudinal axis. Photo source: www.aeroflap.com
Aerobatics on a passenger plane
Let's say right away that in the history of aviation there have been cases of performing a «barrel» on passenger planes. For example, Richard P. Anderson, a professor of aerospace engineering at Embry-Riddle Aeronautical University, says he even personally knows people who have performed barrel rolls on large aircraft. The first such pilot was Alvin Johnston, a test pilot for Boeing. For the first time he showed the «barrel» back in 1955 on a Boeing 367-80, also known as the Dash 80.
Boeing 367-80 — the first passenger aircraft in history to make a loop. Photo source: citizensnip.artstation.com
The pilot wanted to impress Boeing executives who were watching him fly from a yacht on Lake Washington. Then Alvin Johnston not only made two barrels, but also made a shandel — another difficult stunt in which the plane makes a 180-degree turn and simultaneously gains altitude. When the boss called the pilot to his office and asked what he did, the pilot replied — “I’m selling airplanes,” as reported by Plane & Pilot Magazine.
“Barrel” on an airliner — how difficult is it
As Richard P. Anderson reports, physics applies the same to all aircraft, regardless of their size. Therefore, when performing such stunts, it is not the size of the car that is important, but the pilot’s ability to control the amount of g-forces that affect him at the moment of roll.
Scheme of the «barrel». Image source: hobbyarea.ru
As the professor explains, when performing such maneuvers as a “barrel,” the pilot needs to maintain an overload of about 1g, that is, close to what we experience on Earth. By the way, passenger planes sometimes still have to withstand strong overloads when they enter turbulence, but this is not the point now. To carry out the maneuver, the pilot must perform a roll (rotation around its axis) and at the same time raise the nose of the aircraft up, and then let the nose drop down to a reasonable limit. All this is done at a speed of 885-965 km/h.
Thus, the only limitation to performing a roll is the speed of rotation. It is necessary to turn the plane before the nose becomes too inclined downwards. As long as the airplane maintains a reasonable roll, you can perform a roll on it just like on any other airplane. Accordingly, the pilot must have extensive experience to control all these moments.
In addition, there is one more limitation. According to David Haglund, an experienced BBC US pilot, a larger aircraft requires more space to perform the figure. Therefore, the pilot must correctly assess the available space, especially regarding altitude — There must be enough room for maneuver both above and below the aircraft.
Modern aircraft have roll restrictions. Photo source: wikipedia.org
Why is it impossible to perform a “barrel roll” on modern airplanes
So, as we found out that physically performing a «roll» on a large aircraft it is quite possible. However, some manufacturers build restrictions into their aircraft. Perhaps this was done specifically for “Texan Johnstons” so that they would not have the desire to perform aviation stunts on planes that are intended for completely different purposes.
For example, Airbus does not allow pilots to bank the plane more than 60 degrees . To roll more, you need to turn off part of the automatic flight system that controls the aircraft's operating range.
Don't forget to subscribe to our Zen and Telegram channels so you don't miss the most interesting and incredible scientific discoveries!
Finally, we suggest you familiarize yourself with other interesting facts about airplanes, namely — how spoilers and speed brakes provide control. You can follow the link and find out how they work and what function they perform on the plane.