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Boeing 737-800 checks in South Korea extended to Jan. 10

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Engine maker GE joins crash probe

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Mobile phones retrieved from crash site could provide

clues

(Adds ministry briefing)

By Hyunjoo Jin

SEOUL, Jan 3 (Reuters) - GE Aerospace, whose joint

venture made the engines of the Boeing ( BA ) airplane that crashed in

the deadliest aviation disaster on South Korean soil, joined the

investigation as Seoul extended by a week special inspections of

all 101 Boeing 737-800 jets.

The transport ministry extended to Jan.10 its inspections

following the crash of a Boeing 737-800 operated by Jeju Air

that killed 179 people, Joo Jong-wan, the deputy

transport minister for civil aviation, told a press briefing.

"Investigators are in the process of probing the cause of

the accident by piecing together a puzzle," Joo added.

The inspections had initially been set to wrap up on Friday,

but another ministry official said further checks would look

into matters such as whether airlines spent sufficient time on

maintenance and secured parts for repairs.

Video images on social media appear to show smoke emerging

from the plane's right engine in the lead-up to the crash.

Sunday's flight from Bangkok to the southwestern county of

Muan belly-landed and overshot the runway at the regional

airport, exploding into flames after hitting an embankment.

The ministry has said it would examine engines, maintenance

records and landing gear on all 737-800s, with serious

violations leading to suspension of an airline's operations.

The plane's engines are produced by GE Aerospace's CFM

International joint venture with Safran. A media

representative for GE Aerospace did not immediately respond to

Reuters' emailed question about the investigation.

The addition of a GE representative takes to 23 the size of

the investigation team, including 12 Korean investigators and

U.S. representatives from Boeing ( BA ) and the U.S. National

Transportation Safety Board (NTSB).

While the cause of the disaster is still unclear, the crash

could add to headaches faced by Boeing ( BA ) as the planemaker battles

to restore the trust of customers following two fatal 737 MAX

crashes, a mid-air panel blowout, and a seven-week strike.

Unanswered questions include why the aircraft did not deploy

its landing gear and what led the pilot to apparently rush into

a second attempt at landing after telling air traffic control

the plane had suffered a bird strike and declaring an emergency.

South Korea's investigation team said two of its members

would leave for the United States with the flight data recorder

recovered on Monday to analyse the critical data with the NTSB.

Joo expected investigators to finish transcribing the

cockpit voice recording from the doomed aircraft in the next

several days, making a decision later on disclosure of the

transcript.

The ministry also held an emergency meeting with the chief

executives of 11 airlines, including top-ranked Korean Air Lines

and Asiana Airlines, to discuss ways to

beef up aviation safety.

South Korea's acting President Choi Sang-mok urged

investigators on Friday to work swiftly to collect evidence from

the crash scene and analyse data from the cockpit voice

recorder.

On Thursday, police said they were searching Jeju Air and

the operator of Muan International Airport. They banned the

airline's chief executive, Kim E-bae, and an unidentified

official from leaving the country.

Investigators also plan a special inspection of the location

and materials of the airport landing system at airports

elsewhere in South Korea by Jan. 8.

Safety experts said the embankment, designed to prop up the

navigation system that helps pilots make safe descents, was too

rigid and too close to the end of the runway.

Investigators will analyse data on 107 mobile phones

recovered from the crash site, including text messages, for

clues to what happened before the crash, Yonhap News said.