Aircraft lessors are expected to play a significant role in financing the Tata-owned airline's aircraft spending spree, worth an estimated $70 billion or half that after discounts.

Air India Chief Executive Campbell Wilson confirmed the airline had gone to the leasing market with a request for jet financing and said he was not worried about financing the orders following its recent takeover by Tata Group.

When asked whether Air India had sought lessor bids on the 470-plane plane order, Campbell told Reuters on the sidelines of a CAPA India conference that they had on "portions of it".

"Clearly the delivery stream is over quite a number of years. We don't do it all at once."

The first few Airbus A350 aircraft, originally sold to Russia's Aeroflot, are due to arrive later this year.

Wilson expressed confidence in Air India's ability to fund the orders.

"The benefit of having a strong, patient capital provider like Tata does accord us a lot of flexibility."

In sale-leaseback deals, lessors buy jets from an airline the moment they are delivered and rent them back - a potentially profitable deal for both sides if conditions work.

India's largest airline, IndiGo, has regularly used the financing tool for the past decade as it built up a large fleet.

"As India as a country grows, and Indian aviation grows, it will also be viewed as a more mature and maturing market," IndiGo CEO Pieter Elbers told Reuters at the same event.

"If you refer to the mini-banking crisis, these are longer-term leases, so we don't see any (impact)," he told Reuters.

Even so, some experts say lessors may limit exposure to India, which has seen several airline failures and past disputes over the right of lessors to repossess jets. India has ratified a key treaty on lessor rights but has yet to implement it fully.

"Lessors have done a lot of business in India but many will be reluctant to have more than 15% to 20% of their portfolios exposed to India," said aviation adviser Bertrand Grabowski.

"Despite some obvious progress, it remains a complicated, bureaucratic and inefficient jurisdiction, not an easy one for foreign banks," he said in a telephone interview.

(Reporting by Tim Hepher and Aditi Shah in New Delhi; Editing by Josie Kao)

By Tim Hepher and Aditi Shah