Oct 2 (Reuters) - Russia's biggest airline, Aeroflot , plans to raise at least 80 billion roubles ($1.02 billion) in a secondary public offering (SPO) in Moscow, it said on Friday.

State-controlled Aeroflot has been hit by the new coronavirus outbreak this year which grounded most passenger planes around the world.

It, however, believes in long-term structural growth of the Russian passenger aviation market, its chief executive, Vitaly Saveliev, said in a statement.

"The additional equity capital raised via this Offering will put the Aeroflot Group on a firm footing as we continue our recovery from the impact of COVID-19 and build for the future," Saveliev said.

Institutional investors are expected to buy Aeroflot's new shares for up to 39 billion roubles, while the rest will come from existing shareholders, including the Russian government, which aims to maintain its stake in the airline at the current 51.2%, Aeroflot said.

Aeroflot will start investor meetings on Friday. Books are expected to be closed on Oct. 8, a source, familiar with the possible deal, and a financial market source told Reuters.

It aims to use the use proceeds from the deal, being arranged by VTB Capital, for general corporate purposes and deleveraging.

The company plans to issue up to 1.7 billion shares for the deal. Its current shareholders are expected to get 987 million shares, of which 869.9 million shares will be purchased by the Russian government.

Shares in Aeroflot were down 3.2% in Moscow on Friday, underperforming the benchmark index, which was down 1.9%. ($1 = 78.2325 roubles) (Reporting by Anna Rzhevkina and Olga Popova; writing by Anna Rzhevkina and Polina Devitt; editing by Robert Birsel)