NEW DELHI — India has released a global tender for roughly 60 utility helicopters to replace the Indian navy’s vintage Chetak helos. “A request for proposals [RFP] has been issued for buying mainly twin-engine helos. The deal is approximately worth $900 million,” a defense ministry official says. The official says Sikorsky, Eurocopter, Kamov and AgustaWestland are among the likely respondents.