In a boost to U.S. weapons makers looking for ways to offset lower domestic military spending, India is expected to choose Sikorsky Aircraft's S-70B Sea Hawk helicopters at a 16-aircraft tender worth over $1 billion.
The decision could come during a high-profile visit to the United States by new Indian Prime Minister Narendra Modi that starts on Friday.
The Sikorsky deal would be one of several large U.S. arms purchases by India that are nearing completion, including over $2.5 billion in orders for Boeing Co's AH-64D Apache and CH-47 Chinook helicopters.
Sikorsky Aircraft, a unit of United Technologies, declined comment on the potential helicopter order. Sikorsy is expected to beat out NH Industries, a joint venture of Airbus, AgustaWestland and Fokker Aerostructures.
Those deals could in turn lay the groundwork for a much larger order of 123 helicopters for the Indian Navy, said one of the sources, who was not authorized to speak publicly.
Boeing continues to negotiate with India on the Apache and Chinook helicopters and hopes to have signed contracts by the end of the year, said spokeswoman Caroline Hutcheson.
U.S. weapons makers, keen to offset declining U.S. and European military spending, are watching closely to see whether Modi delivers on his promises to expand India's strategic relationship with the United States.
India was the top foreign buyer of U.S. arms last year, according to defense research firm IHS Janes, and the two governments are now negotiating a series of specific defense collaboration projects that would involve more co-production.