South Korea to release preliminary report of Jeju Air crash by Monday

South Korea will release by Monday a preliminary report on last month's Jeju Air plane crash that killed 179 people, the deadliest air disaster on the nation's soil, the transport ministry said on Saturday.

One area under investigation is what role a bird strike played in the Dec. 29 crash of flight 7C2216 as it arrived at Muan International Airport from Bangkok, according to a ministry statement.

The report will be sent to the International Civil Aviation Organization as well as the United States, France and Thailand, the ministry said. Seoul has been cooperating with investigators from the U.S. National Transportation Safety Board and France's Bureau of Enquiry and Analysis for Civil Aviation Safety.

It will take several months to analyse and verify flight data and cockpit voice recordings, which stopped recording four minutes and seven seconds before the crash, and communication recordings with the control tower, the ministry said.

At 08:58:11 a.m., the pilots discussed birds flying under the Boeing 737-800, then declared mayday at 08:58:56, reporting a bird strike while the plane was on a go-around, the statement said. Airport CCTV footage also showed the plane making "contact" with birds during the go-around, it said.

Previously the ministry had said the pilots issued the distress signal due to bird strikes before going around.

The jet crashed at 9:02:57 a.m., slamming into an embankment and bursting into flames that killed everyone aboard except for two crew members in the tail section.

The surveillance footage was taken from too far away to see if there was a spark from the bird strike but it "confirmed the plane making contact with birds, though the exact time is unclear," a ministry official told Reuters.

Duck feathers and blood were found in both of the plane's GE Aerospace engines, the ministry said.

The ministry said it would conduct a separate analysis of the role of the concrete embankment that supported navigation antennas called "localisers". The ministry said on Wednesday that it would remove the embankment, which experts said likely made the disaster more deadly.