A pilot vanished off Boca Raton 3 weeks ago. His disappearance likely will remain a mystery.

Wednesday will mark three weeks since an 87-year-old Boca Raton pilot went missing at sea, and with no agency stepping forward to investigate, the disappearance likely will remain a mystery.

The fact no agency is currently investigating how the pilot, Brendan Spratt, went missing concerned aviation experts. They say agencies usually at least try to piece together what happened in such cases.

“You can interview witnesses,” said Jeffrey Guzetti, a former air safety investigator with the Federal Aviation Administration and National Transportation Security Board. “You can look at any kind of aircraft documents that might have been left behind. You can get weather information, and you open up a file and put a case number on it.”

Disappearing off the coast

The FAA says it lost track of the pilot, Brendan Spratt, about 17 miles southeast of Boca Raton last month. Spratt was returning home from a trip in northern Florida on Feb. 24 when aviation officials say Spratt and his 1991 Lancair 320 plane dropped off the radar.

Spratt’s pilot’s license was revoked by the FAA in 2015. The agency wouldn’t say why, but he was prohibited by law from flying ever since.

When he vanished, a search at sea kicked off: The Coast Guard scoured about 16,000 square miles from Miami to Fort Pierce, but never found any debris. The FAA and NTSB each told the South Florida Sun Sentinel that there would be no inquiry underway unless plane wreckage was retrieved.

Representatives from five other agencies all said they, too, are not investigating, given the disappearance wasn’t in their jurisdiction.

It would be helpful for there to be an investigation, even if the case ultimately remains unsolved, Guzetti said. He said he was shocked to see that the Boca man had no pilot’s license or medical certificate.

A spokeswoman for the Boca Raton Airport — Spratt’s apparent destination, where he owns a hangar — said air traffic in and out of the airport is handled by the FAA, not the airport authority. An FAA spokeswoman said Monday that FAA air traffic controllers had no contact with Spratt before his disappearance.

Longtime pilot

Spratt has been flying nearly his whole life. He learned to fly as a young man and went on to invent numerous airplane safety devices, manage a team of airplane engineers and build his own plane, which he’s flown for 30 years.

While the pilot’s discipline records were not immediately available, he did have one notable run-in with federal officials years ago.

The Volusia County Sheriff’s Office, where Spratt visited frequently, said the only report they have mentioning him is from 2013, where he was accused of violating the airspace of Air Force One, when then-President Barack Obama was on board, en route to West Palm Beach.

Spratt was detained upon landing, but nothing more apparently came from that encounter with the Secret Service.