It has emerged he expressed concerns about the plane on the flight, according to an audio message sent to friends and relatives.
"I'm on a plane that looks like it's going to fall apart, and I'm leaving for Cardiff," Sala said in a WhatsApp audio message carried by Argentine media.
"If in an hour and a half you have no news from me, I don't know if they will send people to look for me, because they will not find me, you know. Dad, I'm so scared," he added.
A 15-hour search Tuesday covering a 1,155 square-mile (3,000 square-kilometre) area in the Channel spotted "a number of floating objects in the water", Guernsey police said on Tuesday.
"We have found no signs of those on board. If they did land on the water, the chances of survival are at this stage, unfortunately, slim," they added.