Jet airliners dominate the commercial aviation industry. They are characterized by a jet engine propulsion system. While some airliners use a propeller-based propulsion system, jet airliners leverage one or more jet engines. They compress and mix air with fuel, after which they ignite it. Ignition creates hot exhaust gases they expel out the back of the jet engine, thereby generating thrust that propels the airplane forward.
#1) Modern Invention
Jet airliners aren’t a new or modern invention; they’ve been around for well over a half-century. Some of the industry’s first jet airliners appeared in the 1950s. Featuring turbojet engines, they were fast but noisy. Since then, many jet airliners have switched to turbofan engines. Turbofans are significantly quieter and more fuel efficient, making them a popular choice for airlines and passengers alike.
#2) Doors Can Open Midflight
Some people assume that the doors of jet airliners can open midflight. Fortunately, this isn’t a concern due to the pressure differential between the cabin and the air outside the airliner. Jet airliners have a cruising altitude of about 30,000 feet. At this altitude, the air outside the airliner is thinner and less dense than the cabin air. This pressure differential creates a “pushing” force that makes cabin doors nearly impossible to open.
#3) All Use the Same Fuel
Another common myth is that all jet airliners use the same fuel. While nearly all jet airliners use a kerosene-based fuel, there are different types of aviation fuel. Common types used by jet airliners include Jet A, Jet A-1 and Jet B. Jet A is the most common and consists of refined kerosene. Jet A offers a lower freezing point of -40 degrees Celsius, whereas Jet B is a kerosene and gasoline mixture that boasts an even lower freezing point.
#4) Autopilot Systems Handle Everything
While most jet airliners today have autopilot systems, they aren’t a substitute for experienced pilots. Pilots must still perform flight planning, monitor key systems, communicate with Air Traffic Control (ATC) and more. Autopilot systems, on the other hand, are typically used for specific tasks like changing the airliner’s heading or altitude.
#5) Cracked Windows Indicate a Critical Failure
Upon seeing a hairline crack in a window, many passengers fear it’s a serious safety hazard. Jet airliners, however, typically feature multiple window layers, including an outer, middle and inner layer. Only the outer and middle window layers are pressurized. Therefore, even if the inner layer is cracked, it won’t jeopardize the airliner’s integrity or safety.
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