A MID-AIR crash that killed three RAF servicemen would have been prevented if collision warning systems had been fitted to their Tornado jets, a new report is expected to reveal today.

This morning the Military Aviation Authority is scheduled to publish the results of its long-awaited report into the tragedy, which took place over the Moray Firth in July 2012.

It is believed that procurement processes at the Ministry of Defence (MoD) will come under fire in the highly critical 300-page document. The processes meant the purchase of the on-board collision-warning system was repeatedly delayed and at one point cancelled.

A system designed to prevent mid-air collisions was recommended in the 1990s and was identified in 2008. However, it has still not been fitted to either the RAF's fleet of Tornados, which have a top speed of almost 1000mph, or its more advanced Typhoon planes.

Squadron Leader Sam Bailey, 36, Flight Lieutenant Hywel Poole, 28, and Flight Lieutenant Adam Sanders, 27, who were based at RAF Lossiemouth, were killed in the crash. Another crew member, Squadron Leader Paul Evans, ejected and was severely injured.

SNP defence ­spokesman Angus Robertson, whose constituency contains the air base, described the repeated delays in installing the system as scandalous and called for a fatal accident inquiry to be set up.

He said: "For this to be confirmed in this report by the Military Aviation Authority would be a damning indictment on the approach the MoD takes to the safety of service personnel.

"It raises very serious questions about the decision-making processes which recommended the installation of collision warning systems in Tornado aircraft in the 1990s, yet they are still not installed."

He added: "It really does make the case for a Fatal Accident Inquiry so the MoD and the people who have made decisions, like Liam Fox, have to answer for the delays.

"As in all tragic cases which involve the death and injury of service personnel our thoughts must be with those directly and indirectly affected. It is imperative that all lessons are learned from the Tornado collision and I know that this has been a top priority for personnel at RAF Lossiemouth."

Investigators are expected to list 19 contributory factors to the crash and make more than 50 recommendations, including that a warning system is brought in urgently.

It is believed they used advanced techniques to simulate the accident, including carrying out a radar trace, which occurred while the crews were on a training exercise.

Last summer, a memorial was unveiled to the pilots killed in the crash. A stone, overlooking the Moray Firth off the Caithness coast, bears their names. Although technically students while completing their flying training, they had qualified as fast-jet pilots.

Following their deaths, senior RAF figures spoke of their "determination, commitment and professionalism" in their duties.

The MoD said it would not comment until the report is published.