New Delhi/ Mumbai, May 6 (PTI) An Air India flight from Toronto to the national capital was diverted to Frankfurt on May 2 due to clogged lavatories, according to sources.

When contacted, an Air India spokesperson said the flight was diverted due to a technical issue.

The airline sources said flight AI188 had to be diverted to Frankfurt as some of the lavatories were unserviceable.

This was at least the second instance in less than two months that an Air India wide body aircraft had to return mid-air due to clogged lavatories. On March 6, flight AI126 from Chicago to Delhi returned to the US city after being airborne for more than 10 hours due to the same issue.

On May 2, flight AI188, operating non-stop from Toronto to Delhi, was diverted to Frankfurt due to a technical issue. "The flight was airborne from Frankfurt within a couple of hours and proceeded to its destination, Delhi," the Air India spokesperson said in a statement.

The flight was operated with a Boeing 7770-337 (ER) aircraft as per information available on flight tracking website Flightradar24.com.

The aircraft was 15.8 years old, according to information from the website Planespotters.net.

One of the sources said there are problems with Air India aircraft operating ultra-long haul routes due to the old fleet and passengers' behaviour.

A majority of the wide body planes operating flights on the US and Canada routes are old due to which the plumbing issues keep cropping up. The pipes are old and interconnected, and whenever a waste tank gets choked, it blocks half of the lavatories of the aircraft. Generally, there are two waste tanks on a wide body plane to which these lavatory pipes are connected, the source added.

Further, the source said that some passengers recklessly throwing garbage in the toilet also results in choking the system.

Air India, on March 10, had issued a detailed statement about the air return of the Chicago-Delhi flight on March 6.

About an hour and forty-five minutes into the flight, the crew reported some of the lavatories in Business and Economy Class to be unserviceable. "Subsequently, eight of the 12 lavatories in the aircraft became unserviceable, causing discomfort to all on board," the airline had said in the statement about flight AI126.

At that time, the airline had also urged passengers to use "lavatories only for the purposes that they are meant for" and mentioned that previously, its teams had found objects like blankets, inner wear, and diapers, among other waste, having been flushed down the toilets on other flights. PTI RAM IAS DR