At least 42 of the 58 passengers and crew on board were killed when TransAsia flight GE235 crashed shortly after take-off from Songshan airport last Wednesday – the twin-engine ATR narrowly missed a block of flats and then clipped a passing taxi and a motorway bridge before plunging into a river.

Taiwan’s aviation regulator ordered the Taipei-based airline’s pilots to be tested on basic operating and emergency procedures after initial findings suggested that pilot error was largely responsible for the crash despite an engine failure.

But the results were hardly reassuring for travellers, with 10 of TransAsia’s 68 pilots now set to undergo further training after they failed the oral aircraft handling test. A further 19 pilots who did not sit the test because they were either ill or not in Taiwan have also been suspended from their duties.

TransAsia chief executive Peter Chen said the results were “not acceptable”. He told a news conference: “We will definitely strengthen their training.”

The dramatic final moments of last week’s doomed flight were captured by a vehicle dash cam as the plane tilted 90 degrees before swooping low across the motorway, hitting the bridge and crashing into the river. The early indications are that the French-made aircraft lost power shortly after take-off. However, the crew are believed to have shut down the other engine, which was working, before trying to restart it shortly before the plane crashed.

Twin-craft aircraft can fly with one working engine, and the worrying indications are that the pilots may have shut down the wrong engine.