BENGALURU, Feb 12 (Reuters) - India is scouting for billions of dollars worth of military planes, completing jetliner deals to meet civilian demand and pressing global aircraft manufacturers to produce more locally at a major air show this week.

Flanked by nuclear-armed rivals China and Pakistan, India has the world's fourth-largest air force but its largely Soviet-era fleet is in desperate need of modernising. It also wants planes for aircraft carriers to balance China's growing power in the Indian Ocean.

As the country prepares to host the Aero India show in Bengaluru from Monday, its airlines are expanding, with Air India expected to announce a potentially record deal to buy nearly 500 jets from Airbus SE (AIR.PA) and Boeing Co (BA.N), worth more than $100 billion at list prices.

IndiGo, the country's biggest carrier and a top Airbus client, could be next, with aviation consultant CAPA India predicting it will make a blockbuster order of a similar scale as Air India's.

Indian carriers may buy 1,500 to 1,700 aircraft in coming years, CAPA said, including Air India and IndiGo.

Prime Minister Narendra Modi is to open the air show, which runs through Friday. It will be military-dominated but also feature India's efforts to accommodate a domestic travel boom and rebuild its brand abroad.

Modi has made "Make-in-India" a centrepiece of his economic policy, insisting that manufacturers such as Lockheed Martin Corp (LMT.N), Boeing and Airbus share technology or make more than parts in the country.

His government's push to expand the world's fifth-largest economy to $5 trillion by 2026 from $3.2 trillion in 2021 could mean more industrial supply deals.