*

Cockpit voice recorder, computer data, engine switch among

evidence -source

*

Investigators have not yet released official report

containing

evidence

*

South Korea cancelled planned media update after briefing

victims' families

By Hyunjoo Jin and Lisa Barrington

SEOUL, July 21 (Reuters) - The South Korea-led

investigation into Jeju Air's fatal plane crash in

December has "clear evidence" that pilots shut off the

less-damaged engine after a bird strike, a source with knowledge

of the probe said on Monday.

The source said the evidence, including the cockpit voice

recorder, computer data and a physical engine switch found in

the wreckage showed pilots shut off the left engine instead of

the right engine when taking emergency steps after a bird strike

just before it was scheduled to land.

"The investigation team has clear evidence and backup data,

so its finding will not change," the source told Reuters on

condition of anonymity because investigators have not released

an official report including this evidence.

A government source said examinations of the plane's

recovered engines found that no defects had been present before

the bird strike and crash.

The December 29 crash of the Boeing 737-800 jet at

Muan Airport killed all but two of the 181 passengers and crew

members on board and was the deadliest air disaster on South

Korean soil.

Investigators told victims' family members at a briefing on

Saturday that the right engine had been more severely damaged by

a bird strike than the left, and there was circumstantial

evidence that pilots had turned off the less-damaged left

engine, according to a third source who was at the briefing.

South Korean media outlets including MBN and Yonhap

reported that information on Saturday and Sunday.

South Korea's Aviation and Railway Accident Investigation

Board (ARAIB), which is leading the investigation, did not

respond immediately to a request for comment.

Boeing ( BA ) referred questions about the crash to ARAIB. Engine

maker CFM International, a joint venture between GE and

France's Safran, did not immediately respond to a

request for comment.

Jeju Air said it was actively cooperating with the ARAIB's

investigation and awaiting the official announcement of the

results.

Most air crashes are caused by multiple factors, and under

international rules, a final report is expected within a year of

an accident.

A preliminary report released in January said duck remains

were found in both engines of the Jeju Air plane after the

flight from Bangkok crashed at Muan Airport, but did not give

details about the extent of remains or damage found in each

engine.

OBJECTIONS FROM VICTIMS' FAMILIES

South Korea's investigation body on Saturday cancelled a

planned release to media of an update on what is known so far

about the engines.

Families of the crash victims were briefed on the report

ahead of its planned release, but objected to its publication,

saying that it appeared to apportion blame to the pilots without

exploring other contributing factors, lawyers representing the

families said.

The Jeju Air flight overshot Muan Airport's runway as it

made an emergency belly landing and crashed into an embankment

containing navigation equipment, leading to a fire and partial

explosion.

Representatives of victims' families and the Jeju Air

pilots' union said over the weekend that the investigation needs

to also focus on the embankment, which aviation experts have

said likely contributed to the high death toll.

The Jeju Air pilots' union said the ARAIB was "misleading

the public" by suggesting there was no problem with the left

engine given traces of bird remains were found in both engines.

The union accused the ARAIB of trying to make pilots

"scapegoats" by failing to provide scientific and technological

grounds that the plane could have landed safely with only the

left engine turned on.

Air accidents are complex incidents that occur due to a

number of contributing factors, and investigators have not

produced evidence so far to support the implication that the

accident was a result of pilot error, the union said.

Investigators are so far "silent about organisational

responsibility", the union said.

A body representing bereaved families said in a statement

there were some phrases related to the cause of the accident in

the planned press release that could be interpreted as if a

final conclusion had been reached, and all facts surrounding the

incident must be clarified.