His explanation: You are more aerodynamic naked.

A man at the Moscow airport is said to have stripped completely naked after security checks.

He is said to have shouted that you become "more aerodynamic" without clothes.
He was then arrested by police. The man, who was born in 1981, was scheduled to fly with Ural Airlines to the Crimean Peninsula. He stripped completely naked after security and moved toward the gate, according to the New York Post.
"He shouted that he was naked because clothes interfere with the body's aerodynamics," a witness told the REN TV channel.

Airport staff stopped the man before he could board the plane. He was then taken to a hospital for examination.

According to witnesses, the man did not appear to be under the influence of alcohol or any other drugs.
Moscow airport.

Source: aftonbladet.se