Rome, November 9 - Vittorio Missoni, the CEO of Italian fashion house Missoni, is bound to turn up after his small plane went missing over Venezuelan waters last week, his eldest son told Italian media Wednesday. "My father will come back," said Ottavio Missoni. "We're expecting it". Vittorio Missoni, whose father founded the fashion house famous for its colourful zig-zag knitwear, was among four Italians on board the flight, including his wife Maurizia Castiglioni and another couple, which went missing without leaving a trace Friday while en route to Caracas after a holiday on an island in the Los Roques Caribbean archipelago. "A plane can't disappear in that way, on a short trip without leaving any traces," added the son. "No one can convince us otherwise unless they have proof. For this reason my brothers and I remain convinced that any number of things could have happened, except that the plane fell into the ocean". Some have speculated that the small aircraft, which also had on board two pilots, was hijacked by drug traffickers. Weather conditions were favorable at the time the plane went missing, but the Los Roques area is notorious for crashes. In 2008 another small plane returning to the Venezuelan mainland from the archipelago disappeared with 14 people aboard, including eight Italians. The younger Missoni said the last he heard of his father was Thursday, when he phoned to tell him that parts for his motorcycle had just arrived. "Yesterday I made arrangements for them to be installed as soon as possible," he said. "That way everything is ready for when he gets back".