New Delhi, Aug. 14 -- Air India and Air India Express will begin screening of all their pilots psychoactive substance from Thursday after the commander of a Phuket-Delhi flight that lost altitude sharply last week tested positive for marijuana, even as the Centre is planning to amend rules to enforce stricter action against pilots testing positive for drugs, people familiar with the matter said. "We have decided to undertake a full screening of all Group pilots for any substances or medications that are not permitted under prevailing regulations. This testing is mandatory and will start today, 13 August 2026," Manish Uppal, head of flight operations, Air India, wrote in an email to all pilots of the group. HT has seen the email. "It will be...