The House of Lords have rejected a fresh attempt to persuade the UK Government to clear the names of two pilots accused of causing the 1994 Chinook helicopter crash.

Four crew members and 25 terrorism experts from Northern Ireland were killed when the RAF aircraft crashed on the Mull of Kintyre in thick fog eight years ago.

A fatal accident inquiry was unable to determine the cause of the crash.

Lord Chalfont has supported the families' cause

However, two air marshals found flight lieutenants Jonathan Tapper, 30, from Burnham Thorpe in Norfolk, and Richard Cook, 28, from Church Crookham, Hants, guilty of ''gross negligence''.

In February a House of Lords committee, chaired by Lord Jauncey, did clear the two men of blame in the crash.

However, its findings were not accepted by the government.

On Tuesday night, Lord Chalfont urged peers to accept the committee's findings and to call on the government to set aside the RAF inquiry finding.

He told peers: "As the Government was unable to accept... the conclusions of Lord Jauncey's committee, I thought it was important that the House should have an opportunity to express its opinion on this somewhat cavalier dismissal by the Executive of the findings of a select committee of this House."

Junior defence minister Lord Bach, replying to the five-hour debate, said: "Although many and varied hypotheses have been put forward to explain the accident, we believe the only realistic explanation is that found by the reviewing officers of the (RAF) Board of Inquiry.

"The constant re-visiting and questioning of the circumstances of this accident can only add to the heartache of all of the 29 bereaved families.

"I strongly believe that it is now time to move on."

Lord Chalfont's amendment was then rejected by 65 votes to 34, a Government majority of 31.