The entire mishap is not to be blamed on the plumbers, of course. First off, they didn't break the damn thing (possibly). Secondly, they just couldn't repair the toilet because, you know, it's an airplane we're talking about, not your average lavatory.
Expecting a toilet to be fixed on a plane by plumber passengers is a bit like having 100 airspace engineers onboard and expecting them to fix a mechanical issue occurring mid-flight.
For the plumbers, the incident was hilarious and ironic.
“We would have liked to fix the restrooms, but unfortunately it had to be done from the outside, and we did not take the opportunity to send a plumber at 10,000 meters,” Frank Olsen, CEO of the company which had 65 plumbers onboard was quoted as saying by the source.
Airplane toilets can break down for several reasons. The most common issues are blocking of the toilet or a full waste tank. Usually, airline regulations state that, depending on the aircraft, there is a limited number of toilets that can be out of order at one point. Should that number be exceeded, the plane pilot is obligated to land the plane at the nearest airport.
In December 2017, a Delta Air Lines flight from New York to Seattle had to fly hundreds of miles off its approved flight path because it had no working toilet and more passenger really-really needed to go. The aircraft landed at ts destination 3.5 hours late.