(Corrects sales figure in paragraph 6 to read $32 bln, not $17 bln)
* To keep minority stakes in firms it sells
* Eyes electronics, optics, machine-building, biotech sales
By Gleb Stolyarov
MOSCOW, March 1 (Reuters) - Russian state conglomerate Rostec has put on hold a plan to list its helicopters business and still intends to list half a dozen other units in coming years, its head, Sergei Chemezov, said.
Rostec, formerly Russian Technologies, met little interest in 2011 when it tried to sell shares in the maker of the Mi8 helicopter - which has gunship and transporter variants.
Chemezov, who served in Soviet intelligence in 1980s East Germany with President Vladimir Putin, said listing Russian Helicopters would make sense once its international business and global service network were more developed.
"Our advisers believe that it would not make sense for Russian Helicopters to carry out an initial public offering now," Chemezov told Reuters in an interview on Friday.
"As soon as markets pick up and we increase the profitability of the asset, we will move. I hope we will manage to do so in the next few years."
Rostec, whose interests span arms to metallurgy, manages the legacy of the Soviet Union's military-industrial complex and had annual sales of $32 billion in 2012.
Chemezov has been criticised for being too acquisitive and failing to restructure loss-making businesses.
He did, however, complete two large stake sales last year - of leading titanium producer VSMPO-Avisma via a management buyout, and of a stake in carmaker AvtoVaz to Franco-Japanese alliance Renault-Nissan .
Rostec retained blocking minority stakes in both companies, giving it an effective right of veto on strategic decisions.
That is a level Chemezov said he planned to keep in Rostec's civilian businesses, and those producing "dual-use" technology that could be converted for military ends.
Russian Helicopters, the world's No.3 helicopter producer, is showing strong top-line growth, with sales up 42 percent in the first half of 2012 to 60.3 billion roubles ($2.0 billion).
Its core operating profit margin, measured as earnings before interest, taxation, depreciation and amortisation (EBITDA), is 15 percent, while its net margin is 5 percent.
"Our helicopters business is developing very positively. Our order book today is 900 machines worth $14 billion. We are booked solid until 2020," said Chemezov.
"What we need to do now is develop our service and maintenance business. We are opening service centres in India, China and Latin America. These are our key markets."
Other Rostec units being prepared for eventual stake sales include measuring instruments and electronic warfare group Radioelectronic Technologies and optical devices group Shvabe, Chemezov said.
Also slated for eventual sale are Russian Electronics, which specialises in microwave engineering, semi-conductor devices and materials; turbine and aero engine maker ODK; and biotechnology, pharmacy and medical equipment group RT-Biotechprom. ($1 = 30.60 roubles) (Writing by Douglas Busvine; Editing by Megan Davies and Dan Lalor)