Aging aircraft, old ducts, scaling in pipes, and passenger behaviour lead to stink

NEW DELHI: Clogged toilets are not new to Air India flights, but the legacy of the old govt-run airline has been flushed across to the new Tata Group-owned company, right in the middle of its modernisation and expansion spree.
For years, cleanup crew of Air India’s long-haul flights has found in holding tanks of blocked lavatories everything from socks to hand towels, plastic bags, underwear and even small pillows given on board.
Just as the Chicago-Delhi flight was forced to return to O’Hare International Airport last Wednesday when eight of its 10 lavatories were clogged, over the years, several of the airline’s Europe and US flights have been forced to divert or return after flying for hours with hundreds of bursting bowels and bladders for similar reasons.
The dumping has gone on regardless of clear signage asking flyers not to throw anything in the commode as that could “clog the toilet and cause inconvenience to you and your fellow passengers”.
As Air India’s legacy Boeing 777s, used for North America nonstops, age, the problem is worsening as the old ducts find it increasingly difficult to suck in whatever indiscreet passengers flush away. “These aircraft are very old. The lavatory ducts or suction pipes have got scaling due to which their available width has reduced. External particles like shawls, sheets or towels easily and immediately clog them up,” said an engineer who has spent decades maintaining aircraft. Aircraft toilets use a vacuum system to remove waste into a storage tank.

According to Air India’s former executive director Jitender Bhargava, the airline got 21 of its 23 B777s between 2007 and 2010. The other two were inducted much later and are now used as dedicated long-haul VVIP planes operated by the Indian Air Force. The B787 Dreamliners, used on the Europe, Far East and Australia routes, came in a few years later, starting 2010, and are also getting old now.
The problem of clogged toilets has shown up on both these long-haul planes in the airline’s fleet. Due to night curfew in Europe, Air India’s affected B777s have in the past returned to either India or North America after flying hours. An engineer explained, “A B777 has two waste tanks. If a duct leading from a lavatory gets clogged, it will affect only that particular lavatory. But if the duct close to the waste tank inlet gets clogged, it will affect all lavatories connected to it.”
On AI 126 being forced to return to Chicago on March 5, Air India said in a statement on Monday, “Our teams found polythene bags, rags and clothes that had been flushed down and stuck in the plumbing. This led the lavatories to become unserviceable. While not found on AI 126 of March 5, 2025, our teams have previously also found objects such as blankets, innerwear, and diapers, among other waste, having been flushed down the toilets on other flights. We take this opportunity to urge passengers to use lavatories only for the purposes that they are meant for.”
Is this problem faced by airlines of other countries as well? TOI spoke to officials of multiple leading foreign airlines, who said they have only experienced this problem sporadically. This suggests passengers behave differently in an Indian carrier than when they are aboard a foreign airline.
“This is a very, very rare occurrence that can happen anywhere. Sometimes, a couple of lavatories may become unserviceable. If detected before taking off from a place that is not our engineering base, we resort to denied boarding and proportionately reduce the number of passengers on that aircraft,” said an official with a foreign airline.
Apart from educating passengers, aircraft maintenance engineers have a word of advice for Air India. “Small bottles are kept in lavatories by AI and almost all other global airlines operating medium to ultra-long hauls. However given the peculiar situation of AI, it will be better to have bigger fixed dispensers that can be refilled by crew as a lot of small bottles end up getting flushed. Ditto for dental hygiene kits but those have to be given,” said an engineer.
Crew members say passengers ignore the waste bins, which are right there, below or beside the wash basin, and flush everything down the toilet instead. Toilets in the economy section are more prone to clogging simply because the passenger load is higher. “Given the impact on reputation for Air India, the management must take a call on whether pre-flight instructions by crew should also include what not to flush in the lavs,” said a crew member.