More than 50 planes of IndiGo and Go First are on the ground due to Pratt & Whitney engine woes amid persisting supply chain headwinds, forcing airlines to explore wet leasing of aircraft and other options to minimise disruptions, according to officials. The country's largest airline IndiGo is looking at various options, including slowing down redeliveries through lease extensions, exploring the re-induction of aircraft into the fleet, and evaluating the wet lease options within the regulatory guidelines.