South Korea will put its "Surion" military helicopter to a formal test again on its anti-icing system within the next several months, the nation's arms agency said Thursday.

The multi-role KUH-1 chopper was once an icon of South Korea's fast-developing defense industry, developed in 2009 by Korea Aerospace Industries in partnership with Airbus Helicopters.

But it has become a source of public concern amid a series of reports of flaws including cracks in the airframe and a problem in the gearbox.

The country's Board of Audit and Inspection has questioned the airworthiness of the twin-engine helicopter.

The audit office even cited a water leakage issue, which the Defense Acquisition Program Administration claimed later has been already resolved.

The DAPA said it's preparing for a test on Surion's anti-icing system in the United States. Surion failed the previous cold-weather test taken in 2015. It failed to meet 29 of the 101 requirements.

"The follow-up test plan has been set. There will a test on the 29 requirements between December this year and March next year," a DAPA official told reporters in a background briefing.

He pointed out the peculiarity of an anti-icing qualification test of a new aircraft that requires certain weather conditions.

"Even in case of major foreign planes, it takes two to five years to prove their anti-icing capability after the completion of the development," the official said.

The UH-60 Black Hawk was developed in 1976 and it passed the test between 1979 and 1981, he added.

South Korea's Army operates more than 60 Surion choppers mainly for carrying troops and equipment.

The DAPA is pushing for the export of the rotorcraft. (Yonhap)