Two and a half years after SpiceJet Ltd. was forced to ground its entire fleet on its inability to pay a mere $2.2 million in fuel bills, the budget airline has become the world's best-performing airline stock -- with $26 billion in plane orders to boot. The company's co-founder and Chairman Ajay Singh has played the white knight, injecting capital, cutting loss-making routes and aggressively adding capacity in one of the world's fastest growing markets. To top it all off, crude prices are staying low. For investors, that's been a winning formula: SpiceJet shares are the best performers on a Bloomberg Intelligence index of airline stocks this year. The stock is up 124 percent in 2017 and has gained more than 800 percent since the company's near-demise in December 2014, giving SpiceJet a market value of $1.2 billion.