Guernsey Police say they will continue the search for the missing plane carrying Emiliano Sala.
A Channel Island Air Search plane explored the island of Burhou, the Casquets, Alderney, the north coast of the Cherbourg Peninsula, north coast of Jersey and then fly over Sark.
By Thursday afternoon, Guernsey Police said there was "no trace of the aircraft".
Guernsey Police confirmed nearly 1,700 square miles had been searched, but nothing had been found.
The plane's pilot was officially named as David Ibbotson from Crowle in Northern Lincolnshire. The father-of-three is a qualified gas engineer with experience of flying including carrying people for parachute jumps.
Minutes before the plane went missing, Sala told friends he "was scared" and "aboard a plane that seems like it is falling to pieces".
John Fitzgerald, chief officer of Channel Island's Air Search says hopes of finding the pair alive are slim:
"I can't see how anybody could survive in such temperatures for that length of time. Looking at sea conditions today [Wednesday] it's very rough out there."
Floating objects were spotted in the water but have not been officially linked to the plane.
Adverse weather conditions have made the search difficult.
Sala had been due to arrive in Cardiff from Nantes on Monday night to begin training with his new teammates this week.
Supporters have been using the #Pray4Sala hashtag on social media and flower tributes have been left outside Cardiff City stadium and in Nantes where he used to play.
Sala played at youth level for Club Proyecto Crecer in his home country before signing for Bordeaux in 2010.
He was then sent out on a series of loans to Orleans, Niort and Caen and, after failing to make more than a handful of appearances for Bordeaux, joined Nantes in 2015.
It was in Brittany where his career began to flourish.
Sala's hat-trick against Toulouse in October 2018 was the first by any Nantes player in Ligue 1 since 2006.
Cardiff signed the forward in a deal reportedly worth in the region of £15million, breaking the previous record of £11million paid for Gary Medel in 2013.