The Directorate General of Civil Aviation on Tuesday moved the National Green Tribunal to seek a stay on and review of its order on the disposal of human waste on flights, PTI reported. The green tribunal had asked the aviation regulator to issue a circular to airlines operating at the Delhi airport to ensure they do not dispose of human waste mid-air.

The regulator has already issued the circular, saying airlines will be penalised Rs 50,000 for disposing of human excreta mid-air, reported The Times of India.

The DGCA said in its plea that it has become a “laughing stock” after the order. It told a green tribunal bench comprising Justice Adarsh Kumar Goel and Justice Jawad Rahim that it was not possible for aircraft to dump human waste from the sky as the designated mechanism for emptying the waste tank cannot be used mid-air.

The bench, however, refused to stay the order, observing that the DGCA has already issued an order to penalise offending airlines. “What is the urgency now?” the bench asked. “We will see it on the next date of hearing.”

Earlier, the bench had given the DGCA till August 31 to comply with its order, warning the aviation regulator for its “repeated defiance”. It had added that non-compliance would lead to the salary of the director general of civil aviation being withheld.

The DGCA had filed a petition in May as well, seeking a review and stay on an earlier order passed in 2016, claiming it was impossible to empty toilet tanks during flight. “The aircraft system has three levels of in-built external protection for disposing the waste,” said the plea. “Under no circumstances is release of waste during flight possible and there has been no such resort ever by the operators. The modern-day airline toilets are sealed, and cannot be emptied in flight. Toilet waste can only be disposed of by manual operation on ground during the aircraft’s servicing.”

The tribunal’s instruction was based on a petition filed by Lieutenant General (retired) Satwant Singh Dahiya alleging that faeces was splattered from an aircraft on his South Delhi house before Diwali in 2016.