MERIDA, Venezuela, Feb 23 (Reuters) - Rescue workers found two flight recorders on Saturday in the wreckage of a passenger plane that veered off course and slammed into the sheer face of an Andean mountain, killing all 46 people on board.

The "black box" recorders may explain what happened in the last moments before local airline Santa Barbara's flight 518 crashed into a 13,000-foot (4,000 meter) rock wall known as Indian Face on Thursday soon after taking off from Merida, a high-altitude tourist town.

Ramon Vinas, who heads Venezuela's civil aviation authority, turned over the boxes to public investigators. He said said one contained recordings of the pilots' conversations and the other held technical data.

Rescuers battling with wind and fog rappelled from helicopters and a camp above the crash site to search for remains in the plane's blue and white wreckage on flame-charred rocks.

For years, Venezuelans have debated whether Merida's airport should be shut because it is hemmed in by mountains, although its accident record is not especially noteworthy.

Before the crash, the weather had been good and the roughly 20-year-old twin-engined plane had a solid maintenance record and no history of technical problems, authorities said.

The experienced pilot had specialized training for flying through the Andes. He made no distress calls before crashing with 43 passengers and a crew of three aboard.

Aircraft are banned from flying from Merida at night. The plane that crashed on Thursday was the day's last flight out.

Santa Barbara is a small airline that covers domestic routes and has seven Merida flights a day. The plane was an ATR 42-300, a turboprop built by ATR, a French-Italian joint venture between EADS <EAD.PA> and Finmeccanica <SIFI.MI>.

French investigators and an ATR team were going to Venezuela to help in the probe of the crash.

Thursday's was the second major air accident in Venezuela this year. Last month, 14 people, including eight Italians and one Swiss passenger, died when a plane crashed into the Caribbean close to a group of Venezuelan islands.

(Reporting by Enrique Andres Pretel and Jorge Silva; Writing by Frank Jack Daniel; Editing by Bill Trott)

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