Have you ever noticed that commercial airliners are always beautifully painted except in the front of the engine? Have you asked why the front of the airplane’s engines are unpainted? There is a very valuable and scientific reason why the front of the engine housing is unpainted and is metallic.
Airliners can travel at an altitude of 40,000 feet, where temperatures can be a bitterly freezing -70 degrees Fahrenheit. Plus, the planes are cruising through clouds full of moisture that could form ice all over the plane. An airliner engine has a lot of parts that, if they became frozen or had ice accumulate, could present a real problem. One of those areas is the front casing of the plane’s engine.
If ice formed on the engine inlet, it would change the shape of the front of the engine cowling or the engine housing, thus altering how the airflow comes into the engine turbine, potentially pushing air away from the intake. Plus, there is the danger that if a lot of ice formed at the front of the engine, it could break off, and huge chunks of ice would fly into the turbine. There is also performance issues with accumulations of ice as well as making the plane heavier.
Airliners also have de-icing systems to prevent catastrophic malfunctions. Hot air is pushed from the engine to hollow areas in the front of the intake edge to prevent ice from forming.
YouTube channel Mentour Pilot explains that the front of the engine is made of metal, and metal is an excellent heat conductor. Painting over the metal on the intake would cut down on the surface area, getting warm from the turbine burning up hot jet fuel. There is also the much less worrisome issue of paint chipping off and being swallowed by the engine or the front of the housing becoming uneven because of a damaged paint job.
To prevent the airliner’s wings from becoming a block of ice, there is an engine bleed valve that has a duct that takes hot air from the engine to the wings to prevent icing, according to the YouTube channel Captain Joe.
Now you have a fun science fact to tell so you sound smart when you’re getting bored to tears by your girlfriend’s humdrum cousin at your New Year’s Eve party.
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