The pilot of Emiliano Sala's plane told friends the aircraft was "dodgy" before the flight that killed the Argentine footballer, it can be revealed.
David Ibbotson is heard in audio exclusively obtained by the BBC saying "I'll be wearing my life jacket" on the journey from France to Wales.
He told a friend he heard a "bang" on a previous flight. The plane crashed into the English Channel in 2019.
It comes as footage shows the last moment the pair were seen alive.
Sala had just become then Premier League side Cardiff City's £15m record signing from French club Nantes when the plane crashed into the English Channel, killing them both.
Technical difficulties.
He was flown by Mr Ibbotson - a part-time pilot who didn't have a licence to carry paying passengers and whose body has never been found - back to western France to say his goodbyes and collect some belongings.
He flew to Nantes on Saturday, 19 January, and planned to return on the Monday - the day of the crash.
Audio of a telephone call to a fellow pilot has been exclusively obtained by the BBC, revealing the technical difficulties Mr Ibbotson had on the journey to France.
In it, he says he heard "a bang" during the flight and complained that he could feel a "very low mist" inside the 35-year-old Piper Malibu plane.
"I'm mid-Channel and 'bang'," Mr Ibbotson told friend, Kevin Jones, about his flight to Nantes.
"I'm flying along and then 'boom'. I thought, 'what's wrong?' So I put everything forward and checked my parameters, everything was good and it was still flying, but it got your attention."
He added: "That Malibu, occasionally you've got like a mist every so often. You can feel it, very, very low throughout the airframe."
Mr Ibbotson, 59, said he also realised the Piper Malibu's left brake pedal wasn't working after landing at Nantes Atlantique Airport. "This aircraft has got to go back in the hangar," he told his friend.
The conversation was accidentally recorded and has since been obtained by the BBC's Transfer: The Emiliano Sala Story podcast.
Ahead of the flight back to Cardiff, Mr Ibbotson added: "Normally I'd have my life jacket between my seats but tomorrow I'll be wearing my life jacket."
The only two people on the plane were Emiliano Sala and Mr Ibbotson, from Crowle, in North Lincolnshire, whose body has never been found.
'Man, I'm scared'
The footballer had also expressed his fears about the aircraft in a voice note sent to his closest friends as the plane was taxiing on the runway at Nantes Atlantique Airport.
The player told them, "man, I'm scared" and that the plane he was on "looks like it's falling apart". "I don't know if someone will look for me because they won't find me," Mr Sala told his friends about a potential crash.
Cardiff City FC had offered their new signing a commercial flight, via Paris, but he wanted more time to say goodbye to friends and team-mates in Nantes before returning to Wales for his first training session with his new club.
So Willie McKay, the man who helped broker the transfer, chartered a private flight - directly between Nantes and Cardiff - through another pilot, David Henderson.
Because Henderson couldn't undertake the request, he called in Mr Ibbotson.
The Argentine did not know Mr Ibbotson wasn't qualified to fly him on that fateful night. The gas fitter was only an amateur pilot and did not have a licence to carry paying passengers or to legally fly in the dark.
The recordings can be heard here.
https://www.bbc.co.uk/news/uk-wales-62594529The documentary can be seen here.
https://www.bbc.co.uk/iplayer/episode/m001c7qg/transfer-the-fate-of-emiliano-sala