Investigators on Friday were examining wreckage and flight data recorders for clues into a plane crash on a Taiwanese island that killed 48 people.

Stormy weather and low visibility are thought to have been factors in Wednesday's crash of the twin propeller ATR-72 operated by TransAsia Airways.

The investigation is expected to focus on a four-minute gap between the pilot's request for a second approach and the plane's crashing into village homes at 19:10, during which visibility dropped by half.

Local media reported on Friday that the plane's cockpit voice recorder and flight data recorder had been sent to the main island of Taiwan for analysis. One of the devices was damaged in the crash and ensuing fire, and it wasn't immediately clear when results of the investigation would be made public.

Dozens of investigators searched for other clues at the crash site on the island of Penghu in the Taiwan Strait west of the capital Taipei.

They took photos and measurements as cranes and backhoes sifted through the wreckage scattered over damaged houses at the far end of the airport on the resort island. Ten people survived the crash.

Also Friday, the airline's chairperson Vincent Lin visited grieving relatives gathered at a local funeral home and said the company would do all it could to aid them in their suffering.

"This is an unpredictable tragedy. The priority for us is to assist victims' relatives," Lin told reporters as Buddhist monks conducted rituals for the dead.

Among the mourners, Shu Chi-tse, father of victim Shu Chong-tai, said he'd spoken to his son just before the flight left the southern city of Kaohsiung on Taiwan's main island.

"He is a good boy. He cares for me and his mom. He loves his grandma a lot," Shu said.

The flight departed despite heavy weather following the passing of a typhoon that had forced the cancellation of about 200 flights earlier in the day. However, aviation authorities said conditions were safe for flying and two other planes had landed at Penghu that day prior to the crash.

The TransAsia crash was Taiwan's first deadly civil aviation accident since 2002, when a China Airlines plane went down shortly after takeoff, killing 225.