Mourners left yellow flowers below the portrait of Argentine football forward Emiliano Sala at the Beauvoir stadium in Nantes following his death in January 2019. Picture: AFP / File / LOIC VENANCE
The Air Accidents Investigation Branch (AAIB) is to present the findings in a briefing at its headquarters in Aldershot, southern England.
Sala, 28, was killed when the plane carrying him and pilot David Ibbotson crashed in the Channel on January 21 2018, days after he had joined then-Premier League Cardiff City from French side Nantes.
The single-propeller Piper PA-46 Malibu aircraft vanished from radar off the Channel island of Guernsey.
Sala’s body was later recovered from the wreckage as part of a private, crowd-funded search, but Ibbotson’s corpse has still not been found.
In August last year, the AAIB said Sala and Ibbotson — who were the only people on board the plane — were likely to have been exposed to “potentially fatal” levels of carbon monoxide.
Exposure at such levels “can reduce or inhibit a pilot’s ability to fly an aircraft depending on the level of that exposure”, it added.
Sala was signed to Cardiff for £15 million ($19 million, 17-million-euro) in a deal that had only been completed a few days before the crash.
The footballer travelled to the Welsh capital to complete the deal, then returned to northwest France to collect belongings and bid farewell to teammates.
Sala was returning to Cardiff to take part in his first training session there.
Following the incident, there were reports the pilot was not licensed to fly at night.
Earlier this week, British police said it would take no further action against a man arrested on suspicion of manslaughter in connection with Sala’s death.
In June 2019, Dorset Police arrested a 64-year-old man from North Yorkshire on suspicion of manslaughter by an unspecified unlawful act.
But Detective Inspector Simon Huxter said police “will not be seeking a formal charging decision… in relation to homicide offences”.
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