PILOT error was yesterday blamed for an Army helicopter crash in the former Yugoslavia in which four soldiers died.

The Army Air Corps Lynx plunged into the sea off Ploce in Croatia in August 1995 after failing to pull out from a low-level manoeuvre.

The commander, Sergeant Martin Osborne, 30, who was flying the aircraft at the time, swam clear but drowned after ''courageously'' diving down to try to save his colleagues who were still trapped in the wreckage.

One soldier on board survived after managing to swim to safety.

A Ministry of Defence Board of Inquiry yesterday concluded that ''the aircraft commander handled the aircraft in such a manner as to fly it into the sea''.

Asked if that meant pilot error was responsible for the crash, a senior MoD source said: ''I believe so''.

The Board also found that Sgt Osborne had ''technically'' been medically grounded at the time of the accident.

Three days earlier he had been ordered by a doctor not to fly for three days because of what was described as a ''relatively minor complaint'' and had not received medical clearance to fly again.

The accident happened during a training exercise while the crew was preparing for operations in the former Yugoslavia with the United Nations Rapid Reaction Force.

The other pilot on board, Corporal Iain MacDonald, 29, had twice performed an evasive manoeuvre, designed to break the ''lock'' of an air defence missile system, diving down steeply from 1000ft and then pulling up at the last minute.

Sgt Osborne then tried to repeat the same manoeuvre but failed to pull out of the dive and the helicopter crashed into the sea.

Sgt Osborne, Cpl Iain MacDonald, and air troopers Roger Willinggale, 22, and Graham Witherstone, 20, all died.

There will now be a coroner's inquest into their deaths.