PHOENIX - Luke Air Force Base pilots didn't intentionally draw penis-shaped contrails in the sky during a Tuesday afternoon training flight, according to the base.

The base is responding to photos of the contrails taken earlier this week that are circulating on social media.

The photos show two loops at either end of a half-oval-shaped trail. Fox 10 in Phoenix was first to report on the photos on Wednesday.

This likely isn't the first time military pilots have been caught in the act, drawing what appear to be sky genitalia.

About a year ago, a similar phallic symbol was spotted in the sky above Germany, according to Navy Times. Another was seen above Washington in 2017.

Base leadership of the U.S. Air Force's 56th Fighter Wing looked at the photos, reviewed flight audio and confirmed the shapes were made unintentionally as part of standard fighter training maneuvers, said Becky Heyse, a base spokesperson.

"There was no nefarious or inappropriate behavior during the training flight," Heyse said.

At the time, pilots were conducting training in the Gladden and Bagdad military operating airspace, Heyse said.

The contrails were made as the planes were beginning to simulate a dogfight, Heyse said, and the circles were made when pilots hooked back to reposition themselves.

The photos didn't show a third vertical contrail, parallel to the other two in the photo, Heyse said.

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