The father of Emiliano Sala said the footballer was ''abandoned'' and left “like a dog” after his £15m transfer deal to Cardiff City.
Horacio Sala died in April but made his comments to BBC Wales in a documentary.
Mr Sala said all parties involved in the transfer – including clubs and agents – should have made more of an effort to look after the welfare of his son.
Argentinian Sala, 28, had just signed from French side Nantes and was making his way to the Welsh city when he disappeared with the pilot of the Piper Malibu into the English Channel north of Guernsey on January 21.
His body was recovered more than ten days later following an extensive search.
Pilot David Ibbotson, 59, of Crowle, Lincolnshire, has not been located.
Mr Sala said: “I always expected to find him alive, but when the news said the plane was in the sea, it became impossible.
“Why was it so hard for them to find something safe? Why couldn’t they?
“They left him alone, they left him alone like a dog. They abandoned him.”
Emiliano's mother, Mercedes Taffarel, added: “It still hurts so much.
“I think he’s going to call me on the phone, but no. It’s terrible, a pain that I can’t explain.”
The family want someone to be held accountable for the death, the BBC reported.
An investigation into the plane crash will focus on the validity of the pilot’s licence.
The Air Accidents Investigation Branch (AAIB) named “regulatory requirements” as one of four areas in which further work will be carried out.
Its interim report noted that the type of licence held by the pilot meant he could only fly passengers in the European Union on a cost-sharing basis, rather than for commercial flights.
Pilots with his licence “must have a bona fide purpose for making the flight”, according to the AAIB.