Sailors conduct preflight checks on an EA-18G Growler assigned to Electronic Attack Squadron 130 on the flight deck of the USS Dwight D. Eisenhower in the Mediterranean Sea. (Navy photo by Petty Officer 3rd Class Nathan T. Beard)

Residents of Washington state turned their eyes to a clear blue sky Thursday and found themselves staring at a cartoonish rendering of male genitalia, sketched in airplane exhaust by at least one Navy EA-18G Growler jet.

The image stretched hundreds of feet high over the Okanogan Highlands, based on photographs shared on social media. It has spawned a full Navy investigation, with a senior officer, Vice Adm. Mike Shoemaker, promising to examine the issue fully and respond.

“The American people rightfully expect that those who wear the Wings of Gold exhibit a level of maturity commensurate with the missions and aircraft with which they’ve been entrusted,” said Shoemaker, who oversees naval air operations, in a statement released by the service. “Naval aviation continually strives to foster an environment of dignity and respect. Sophomoric and immature antics of a sexual nature have no place in Naval aviation today.”

The unit involved, Electronic Attack Squadron 130 of Naval Air Station Whidbey Island, flies a two-person variant of the F/A-18 Super Hornet and specializes in electronic warfare. The aircrew responsible has not been identified.

The Defense Department has placed heightened emphasis on sexual harassment and sexual assault in the ranks. And while it’s not immediately clear what this investigation will yield, it’s evident that the Navy is taking it very seriously.

This is not the first time a military pilot has drawn similar images. As the Drive pointed out, a Royal Air Force jet drew what appeared to be a penis in the sky over Scotland in 2014. The RAF later concluded the suggestive smoke trails were caused by a pilot circling in a holding pattern while waiting to land.

In the United States, the Navy’s elite flight demonstration squadron, the Blue Angels, also was cited in an investigation released in 2014 for painting a giant penis on the roof of a trailer at its winter training home in El Centro, Calif, where pilots could see it from above. The blue-and-gold painting was so large that it could be seen on satellite imagery available on Google Maps, the Navy found.

The Blue Angels’ commanding officer at the time, Navy Capt. Gregory McWherter, was reprimanded for failing to stop sexual harassment and condoning pornography and homophobia in the workplace. Investigators also cited his call sign, “Stiffy.”

“This Commanding Officer witnessed, accepted, and encouraged behavior that, while juvenile and sophomoric in the beginning, ultimately and in the aggregate, became destructive, toxic and hostile,” the Navy’s report said. Under his command, the Blue Angels environment “ran counter to established Navy standards and the Uniform Code of Military Justice, and dramatically weakened good order and discipline.”

It’s unclear what fate awaits the pilot in this latest incident. According to a Navy Department manual released earlier this year, incidents of sexual harassment “cover a wide range of behaviors, from verbal comments to physical acts, and can be subtle or overt.”

If the skywriting over Washington is determined to be sexual harassment aimed at someone in the same squadron, service members involved could be subject to formal counseling, negative fitness reports that hurt careers, administrative punishment, or court-martial and separation from the service.

As the photographs of the skywriting circulated online Friday morning, more than 100 people sent stories about the incident to Maximilian Uriarte, a Marine Corps veteran who draws the popular military-themed web comic “Terminal Lance.” Drawing male genitalia is a running joke in his comic. Doing so, he said, is a way that service members joke around with one another in what is still a hyper-masculine culture.

“I don’t know how much the culture of these pilots is embroiled in inappropriate things, but I think that drawing a penis is just meant to be funny,” he said. “For some reason, when you get into a situation where you need to draw something, it’s always a penis.”

He paused for a second.

“I’d love to offer real insight on this,” he said. “But I don’t know that there is much to be had.”

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