Defense electronics company Elbit Systems has finally signed a EU57.3 million contract with the Bulgarian government to upgrade Soviet-era helicopters. Elbit said on Sunday it would upgrade 12 MI-24 combat helicopters and six MI-17 transport helicopters to bring them in line with the standards used by members of the North Atlantic Treaty Organization (NATO). Elbit expects the program, which it will carry out in cooperation with the Bulgarian aerospace and defense industries, to last three years. Elbit originally was chosen to carry out the contract last December in partnership with US company Lockheed Martin, but the Bulgarian government halted the process in March, saying Elbit failed to meet the tender criteria. Elbit took the Bulgarian government to court, which then ordered the ministry to proceed with the contract. Around that time, Lockheed Martin dropped out of the agreement. The deal adds to a number of recent tenders won by Elbit, including two contracts worth $25m. to upgrade helicopters for the Romanian air force and navy and a $70m. contract from the US Marine Corps Systems Command to supply equipment for use in its vehicles. Last month, the company won a $100m. order from Boeing for 500 of its joint helmet-mounted cueing systems. Last week, Elbit completed a deal that resulted in its ownership of 70 percent of Elisra Defense Group and 39% of Tadiran Communications. Elbit bought the shares from holding company Koor Industries, paying about $68.8m. in cash for the Elisra stake and $59.3m for Koor's remaining 13% of Tadiran. Elbit's shares closed up 1.4% at NIS 1.41 on the Tel Aviv Stock Exchange on Sunday.