Indonesia's Sriwijaya Air plans March equity IPO

* Group CEO Lie says IPO planned in March, declines to detail size

* Exec says 3 Boeing 777-200s ordered, will lift fleet size to 57 (Adds details of plan, industry background)

JAKARTA, Sept 26 (Reuters) - Indonesian airline operator PT Sriwijaya Air plans to launch an initial public offering (IPO) of equity shares in March, owner and group chief executive Chandra Lie told reporters on Monday.

Sriwijaya Air's plan to go public next year comes as domestic rival Lion Air, the country's biggest budget carrier, is also considering floating its shares on the stock market.

Lie declined to disclose the size of the planned share sale. He said bankers for the IPO have been appointed but declined to name them.

"We are preparing. We will make sure this company is good and fit (for an IPO)," vice director of finance Lukcimo Jahja told reporters separately.

Sriwijaya Air, which is categorized as a medium-service airline, has a current fleet of 54 airplanes. It has ordered three Boeing 777-200s to cater to flights for Indonesian haj pilgrimage travellers, which will start arriving next year, Jahja said.

Without disclosing the amount, Jahja said the company saw significant revenue increase last year due to flight route expansion, including an additional flight to China.

Sriwijaya Air carried more than 800,000 passengers per month, according to its website. In comparison, flag carrier PT Garuda Indonesia Tbk and its subsidiary carried more than 2.7 million passengers per month in 2015.

(Reporting by Cindy Silviana; Additional reporting by Fransiska Nangoy; Editing by Muralikumar Anantharaman)