New Delhi : SpiceJet's Chief Operating Officer Sanjiv Kapoor on Thursday put in his papers, nearly ten months after original promoter Ajay Singh took over the reins of the budget airline. Kapoor, 48, was appointed to the post by then owner Kalanithi Maran in November 2013. His abrupt resignation comes over a year before the expiry of his employment contract, SpiceJet sources said. Kapoor is believed to have been sidelined after the new management took over earlier this year following the Marans offloading their entire holding to Singh. An avid user of micro blogging site Twitter, Kapoor has been a visible face of the no-frills airline and a strong supporter of flash sales of discounted tickets. When contacted, Kapoor did not offer any comment. SpiceJet spokesperson also declined to comment. The carrier has seen many senior-level exits since the change in ownership.