Campaigners claimed the crash was caused by mechanical faults
The BBC understands that two RAF pilots will not be cleared of blame for the 1994 Chinook helicopter crash on the Mull of Kintyre.
Jonathan Tapper and Richard Cook, who died along with 27 others, were found guilty of gross negligence by two RAF air marshals.
Defence Secretary John Hutton has decided that no new evidence has been uncovered after a review of the case.
He told campaigners the findings against the pilots will stand.
BBC Westminster reporter Tim Reid said campaigners would be disappointed by his decision.
The helicopter crash happened in thick fog en route from Northern Ireland to Inverness.
Mr Tapper and Mr Cook were initially cleared of blame.
But the decision was overturned two years after a fatal accident inquiry by two senior RAF officers, who claimed they had been flying too fast and too low in thick fog.
However, campaigners have always disputed the claim, insisting it was unfair and unfounded.
They had persuaded the former Defence Secretary Des Browne to review the case a year ago, handing over a dossier which they claimed would clear the pilots, and had then urged Mr Hutton to take up the case.
Among those killed were special forces crew and 25 senior members of Northern Ireland's intelligence community.
Campaigners have previously claimed there were serious flaws in the Chinook helicopter that were more likely to have been responsible for the crash.