China Airlines second 'black box' found

All 225 passengers on board China Airlines flight CI 611 perished in the crash

TAIPEI, Taiwan (CNN) -- Search teams have recovered the second 'black box' from the China Airlines plane that broke up over the Taiwan Strait in May, killing all 225 on board.

The flight data recorder box which logs flight information was located Wednesday around 300 meters (984 feet) from where the cockpit voice recorder was retrieved a day earlier.

The cockpit recorder details conversations between the pilots of the ill-fated plane and air traffic controllers.

It is hoped the two devices -- found in water deeper than 60 meters (200 feet) near Taiwan's Penghu island chain -- will provide important clues as to why the 23-year old Boeing 747-200 crashed about 20 minutes after take off from Taipei en route to Hong Kong.

The two boxes will be brought back to Taiwan later on Wednesday for analysis.

Low visibility and strong currents had hampered deep sea efforts to retrieve the 'black boxes' which usually stop emitting beacon signals after about 30 days.

So far, only 123 bodies and a small section of wreckage from flight CI611 have been recovered.

Crash theories

ANALYSIS • China Airlines' troubled history    EXTRA INFORMATION Gallery: Taiwan tragedy  Timeline: Major air disasters in Asia     CNN.com Asia More news from our Asia edition

Several theories have been floated as to why the plane broke apart at 30,000 feet (9,000 meters) and crashed into the sea.

One theory is that structural problems or a sudden cabin depressurization caused the break up of jetliner. The airline planned to retire the plane from its fleet this month.

Another theory is that the plane's cargo or fuel tanks exploded, causing it to break up, or the plane was the victim of a military accident, although the latter has been ruled out by Taiwan military officials.

Air traffic control radar showed the plane breaking up into four sections. One chunk of the jet shot backward at a high speed, as if propelled by a blast. The other three parts kept going forward.

U.S. experts who probed the mid-air explosion of a Trans World Airlines Boeing 747 in 1996 have joined the investigation to help find out why the aircraft broke up at an altitude of 30,000 feet and plunged into the ocean.

The slow pace of the investigation and recovery of bodies has caused anger among families of the victims, many of whom have hit out at the government over state-owned China Airlines' poor safety record. (China Airlines' troubled history)

The May 25 crash was China Airlines' fourth fatal accident since 1994. The four accidents have claimed more than 650 lives.