This is not an April Fool's Day joke. Or maybe it is, just not intentionally.

On Friday, United Airlines Flight 59, from Frankfurt, Germany, bound for San Francisco, had to divert back to Frankfurt due to an inflight emergency. The emergency? An overflowing toilet, following which the poop really hit the fan.

United Flight 59 took off from Frankfurt, Germany, on Friday afternoon and was headed for San Francisco, California, before it had to reverse course a couple of hours into the flight, according to German news outlet Bild.

The contents of at least one of the toilets overflowed from the tank.

 "On Friday, March 29, United Flight 59 returned to Frankfurt following a maintenance issue with one of the aircraft’s lavatories," a spokesperson for United Airlines told the U.S. Sun.

Passengers aboard the flight were offered hotel rooms for the night and rebooked on other flights the following day, the spokesperson said.

The Boeing 777 circled over the North Sea as the flight crew attempted to figure out if the problem could be resolved before it was eventually flown back to Frankfurt.

Dealing with an emergency like this is a real stinker. One has to expect that it took some time to get everyone off the plane and into hotel rooms; it's certain that, by that time, the passengers were all pooped. The flight crew, who had to deal with the emergency, were said to be completely wiped out.

Rumor has it that United wanted to keep this quiet, out of the eyes of the media, but they were afraid of the embarrassment of having a stool pigeon expose them.

United has had several incidents in the last few weeks.

On Friday, several passengers on a flight from Israel to Newark were hospitalized after the aircraft, a Boeing 777-20, was forced to divert to New York’s Stewart International Airport due to high winds.

Earlier in March, a flight heading to San Francisco was forced to return to Sydney Kingsford Smith Airport in Australia over what the airline called a "maintenance issue." Video captured by an aviation enthusiast appeared to show fluid leaking from the wheel area of the Boeing 777-300 during takeoff.

These incidents have provoked a lot of serious discussion, including United's favoring of Diversity, Equity & Inclusion (DEI) hiring and staffing practices, although there is (as yet) no indication that these policies had any impact on this incident.

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Emergencies like this are not only potentially dangerous but present a significant inconvenience for travelers whose plans just went down the toilet. Even so, once the emergency was underway, the flight crew doubtlessly did all they could to wipe away all the liquid assets.

A final rumor has it that the flight, arriving back at Frankfurt, was greeted by an unexpected retinue of dung beetles, who inquired, "Is this stool taken?"

I had one more pun in mind, but I'm dropping it — it stinks. So, to the folks at United who are dealing with yet another crisis, I can only say: This, too, shall pass.