TAIPEI // The pilot of a passenger plane that crashed in Taiwan killing 43 people mistakenly shut down the aircraft’s only working engine following a glitch with the other engine, investigators said on Thursday.

Eight seconds before the crash, Taiwan’s aviation safety council report states, the pilot said in Chinese: “Wow, pulled back wrong throttle.”

TransAsia Airways flight GE235 clipped a bridge and plunged into a river shortly after take-off from Taipei’s Songshan airport on February 4, 2015, with 53 passengers and five crew on board. Only 15 people survived.

Disturbing cockpit transcripts revealed by the council showed pilots trying to deal with an engine which had lost power, but then reducing the thrust of the other, functioning engine.

Thursday’s report showed that the plane climbed to 365 metres before a warning alarm sounded.

That alarm showed the plane’s second engine as having undergone “flameout at take off”.

The failed engine was referred to as Engine Two by the warning signal, but the pilot at the controls said: “I will pull back Engine One throttle.”

Chaos then ensued with both engines failing as the pilots tried to restart them in the few seconds before the crash.

The last words from the black box recordings were the monitoring pilot shouting: “Impact, impact, brace for impact.”

Dramatic car dashcam images at the time showed the plane hitting an elevated road as it banked steeply away from buildings before crashing into the Keelung river.

“As the pilot pulled back the wrong throttle, for some time both engines were powerless,” said Thomas Wang, head of the aviation council.

Mr Wang also confirmed previous reports that the pilot had failed a simulator test for engine failure on take-off last year, but passed a later retake.

Investigators refused to name the pilot at the controls but reports at the time of the crash identified him as Liao Chien-tsung.

Initially Liao was hailed as a hero for steering the plane away from houses and into the river as it came hurtling down.

“Why the pilot did this, we don’t know. That’s the main task for our [final] analysis report,” said Mr Wang over the decision to pull back the throttle on Engine One.

The draft of that report is due out in November with the final report expected in April 2016.

Thursday’s evidence was described as a “factual report” giving more detail about the crash, but not attributing responsibility or drawing final conclusions about the cause.

Taiwan’s aviation regulator ordered TransAsia pilots to take an oral test on basic operating and emergency procedures for the French-made aircraft after the initial findings pointed to pilot error.

* Agence France-Presse, with additional reporting from Associated Press