This article is more than 1 year old

This article is more than 1 year old

The plane that crashed in the Channel carrying the Cardiff City footballer Emiliano Sala fell thousands of feet in the space of 20 seconds after making a 180-degree turn, minutes after the pilot requested a descent, air accident investigators have found.

The wreckage of the Piper Malibu light aircraft was found on the seabed 30 metres from where final radar readings located it at an altitude of 1,600ft (488 metres), suggesting it dropped almost vertically in its final moments, according to an interim report from the Air Accident Investigations Board.

Facebook Twitter Pinterest Underwater wreckage of the Piper Malibu aircraft on the seabed. Photograph: Air Accidents Investigation Branch HANDOUT/EPA

Investigators have not concluded what caused the plane to crash, but the pilot requested a descent four minutes earlier, apparently to avoid cloud and maintain vision. Unconfirmed radar readings indicate the plane may have climbed rapidly before its final descent.

The AAIB said its ongoing investigation would focus on trying to understand the radar readings from the last moments of the flight, as well as analysing the possible contribution of bad weather.

Investigators have also queried the legal status of the flight and the pilot’s licence to carry Sala.

Cardiff City FC said: “We have grave concerns that questions still remain over the validity of the pilot’s licence and rating to undertake such a journey, as identified [by the AAIB report].

“We are also concerned to discover that the trip involved an aircraft which did not conform to either UK Civil Aviation Authority or US Federal Aviation Administration requirements for commercial activity and therefore may have been operating unlawfully. We welcome further investigation into the accident.”

Sala, 28, died of head and trunk injuries, according to a postmortem examination, when the aircraft crashed at 8.16pm on 21 January on its way from Nantes to Cardiff.

The missing pilot, David Ibbotson, 59, has yet to be located. The wreckage of the fuselage – in three pieces, with wings and tailfin missing – was found on the seabed, 68 metres below the surface, off Guernsey in the Channel Islands on 3 February. Sala’s body was recovered and identified three days later.

Challenging weather conditions made it too difficult to recover the plane wreckage from the sea, and instead the AAIB obtained evidence from extensive video captured by a remotely operated underwater vehicle.

The family of Ibbotson, from Crowle in Lincolnshire, hope that a fresh search for the pilot’s body will begin this week, after an online crowdfunding campaign raised more than £250,000.