Flight Crew Forced to Scoop Poop From Toilet to Sink on 15-Hour Journey

Philippine Airlines may want to invest in a certified plumber to fly with the rest of its crew ... because a recent bathroom accident caught attendants with their pants down.

Horrifying video has come out from a recent 15-hour flight from Los Angeles to the Philippines ... which shows crew members manually removing human waste from the toilet and putting it in the sink after all 11 onboard toilets failed mid-flight.

Watch the video at your own risk ... a worker -- wearing gloves and a thin surgical mask -- repeatedly dips what looks like a bucket into the overflowing toilet and removes waste, which is then drained down the sink. It's unclear how long the worker had to repeat this action.

This failure reportedly occurred six hours from the nearest diversion airport in Guam ... but the flight's captain apparently refused an emergency diversion. The aircraft landed at Ninoy Aquino International Airport in Manila on time.

The process apparently occurred behind closed doors after a supervisor allegedly demanded attendants clean the bathrooms. Passengers reportedly didn't file formal complaints -- though the crew complained to the Philippine Airlines union, which has criticized the handling of the situation.