The U.S. Navy is not amused by an “obscene” drawing left behind by a naval jet flying over a rural Washington community on Thursday.

The air crew has been grounded and an investigation is underway, says an official for Naval Air Station Whidbey Island. The Navy also apologized to anyone offended by the image.

Many residents spotted the condensed air trail that appears to depict male genitalia in clear blue skies. Some posted pictures to social media.

The air crew was flying an F/A-18 Growler assigned to Electronic Attack Squadron 130, Thomas Mills, a public affairs specialist with Naval Air Station Whidbey Island, said in a statement released to CTVNews.ca on Friday afternoon.

The crew left behind what resembled “an obscene image to observers on the ground.”

“The officers and sailors of the United States Navy are professionals, held to the highest standards, while serving our nation with pride around the world. The actions of this aircrew were wholly unacceptable and antithetical to Navy core values. We have grounded the aircrew and are conducting a thorough investigation ¬- and we will hold those responsible accountable for their actions. The Navy apologizes for this irresponsible and immature act.”

An official with the Federal Aviation Authority told local media that unless the act poses a safety risk, there is nothing they can do about it. The official said they “cannot police morality.”