There is “no hope” of finding missing Cardiff City footballer Emiliano Sala and a pilot alive, a rescuer has said.
The striker and the pilot, named as David Ibbotson, were in the plane that vanished from radar on Monday.
Channel Islands Air Search chief officer John Fitzgerald said “even the most fit person” would only survive for a few hours in the water.
Police said the search to find the Argentine striker, 28, and Mr Ibbotson, from Crowle, Lincolnshire, was ongoing.
Sala reportedly sent a WhatsApp voice message to family. Sounding conversational and jokey, he said he was “so scared”.
Media in Argentina reported he said: “I’m on a plane that looks like it’s going to fall apart.”
Guernsey Police said there were three planes and one helicopter in the air as part of efforts to find traces of the Piper Malibu plane.
The force said: “There is as yet no trace today of the missing aircraft. The search is ongoing and a decision whether to continue will be taken later today.”
Officers are also “reviewing satellite imagery and mobile phone data to see if they can be of any assistance in the search”.
Sala was heading to the Welsh capital after signing for the Bluebirds from French club Nantes in a £15m deal.
The single-engine plane left Nantes, north-west France, at 19:15 on Monday and had been flying at 5,000ft (1,500m) over the Channel Islands when it contacted Jersey air traffic control requesting descent.
It lost contact while at 2,300ft (700m) and disappeared off radar near the Casquets lighthouse, infamous among mariners as the site of many shipwrecks, eight miles (13km) north-west of Alderney.
Mr Fitzgerald said: “Sadly, I really don’t think, personally, there is any hope. At this time of year the conditions out there are pretty horrendous if you are actually in the water.”
Guernsey Police is working on four possibilities, including that the “aircraft broke up on contact with the water, leaving them in the sea” and they “landed on water and made it into the life raft we know was on board”.
“Our search area is prioritised on the life raft option,” the force added.
Jersey’s inshore lifeboat followed up on reports of debris in Bouley Bay, which is in the north of the island, but failed to find any debris.
Meanwhile, Cardiff City chairman Mehmet Dalman said there were no plans to rearrange the Bluebirds’ next Premier League match against Arsenal at Emirates Stadium on 29 January.
Mr Dalman said players and fans were in a “state of shock” and the club had received messages of support from around the world.
The “family of football has a way of coming together at times of tragedy,” he told BBC Radio Wales’ Good Morning Wales.
He also confirmed the club had not booked the plane and Sala had “made his own arrangements”.
“We will not leave a single stone unturned until we have all the facts,” added Mr Dalman.
Air and sea crews from the Channel Islands, France and the UK took part in a 15-hour search on Tuesday, but found no trace of the aircraft, Sala or Mr Ibbotson.
Guernsey Police was not able to confirm if floating objects seen belonged to the aircraft and warned that chances of passenger survival were “slim”.
Sala’s father Horacio told Argentine media on Tuesday: “The hours go by and it makes me think of the worst.
“I just want them to find him. The last thing they said is that the communication ended when they crossed the river [English Channel].”