By Sarp Ozer and Ahmet Sertan Usul
ANKARA (AA) - A helicopter that crashed in Istanbul on Monday was on test flight, according to Turkish military sources.
At least four soldiers were martyred in the crash during an emergency landing in Istanbul near a residential area in Cekmekoy district.
Military officials said after a crash Nov. 26 in Istanbul, some 126 UH-1-type crafts were allowed to fly after successfully completing engine tests.