John Robson, Calum Grierson, Ian Kelly, Danny Docherty and Aitken Hunter were drinking in the pub, where they met each month, when a police helicopter plunged through its roof four months ago. The group met there on the last Friday of every month, along with friend Joe Cusker, who was fatally injured. But it was only through a twist of fate that they were caught up in the area of the bar that bore the brunt of the crash.
Mr Robson said the group were late getting into the Clutha and the corner they usually stood at was occupied, so they ended up near the door.
He said: "If we had been in the other corner, we would have all walked out."
Speaking ahead of a memorial service taking place today, another of the group, Mr Kelly, said that he struggled to take in what had happened, adding that what had been a "bright, vibrant scene, suddenly became dark".
He said: "Your brain could not take in the calamity that had taken place. We had no idea what had happened. All we knew is that our friends were standing there one minute, laughing and joking, and all of a sudden there was nothing."
Another of the group, Mr Docherty, said they and their families had been deeply affected, "physically and emotionally" by what had happened.
The Police Scotland Eurocopter EC 135 came down on the Clutha bar at about 10.25pm on November 29. Since the crash, the Air Accident Investigation Branch has said the helicopter suffered a double engine failure.
A report issued on February 14 said both engines "flamed out" but it did not pinpoint the cause.
Today at 11am, Archbishop Philip Tartaglia led the Clutha Helicopter Memorial Service at St Andrew's Cathedral in Glasgow.