Fire chief relives Twin Towers horror

There is a moment New York Fire Chief Joe Callan replays in his mind like an endless loop of video tape.

It is 9.20am on the morning of 11 September and he realises the futility and overwhelming danger of sending his men to battle the twin infernos of the World Trade Center. He gives the order to evacuate - but they do not hear him.

Chief Callan will today relive the morning 343 firefighters died in the worst tragedy in the service's history at the Emergency Planning Society's conference in Bournemouth. As the guest of honour, he will tell of the lives lost - and the lessons, hopefully, learned.

"Why did we send so many men upstairs?" he asks. "Why did we not find another way to communicate with them? I try to avoid thinking like that, but so many were lost, it is difficult not to."

He says: "It was hard to talk about it the first time but I have done three or four of these [talks] now and it seems to have gotten a little easier."

A catastrophic communications failure on the day two planes were f lown into the World Trade Center meant the radio message for the firefighters to retreat - sent half an hour before the collapse of the first tower - never r e a ched many battling their way to the upper floors.

Chief Callan is sitting in his office at the headquarters of the New York Fire Department in Brooklyn. On the streets outside, a heatwave is pushing the temperature close to 100F, but the chief is as cool as his air-conditioning. He is not a large man. The only obvious signs of his status after 36 years of service are the three gold stars on each collar and the word "chief " on his belt buckle.

At 59 he might be mistaken for a pen-pusher except for his aura of calm authority. He is the sort of man you would have wanted beside you on that terrible day. But, as he reveals, there was nothing he could do to prevent the catastrophe.

The impact of the aircraft, and the fires that raged afterwards, destroyed the relay systems that boosted the firefighters' walkie-talkies. And on their own, the radios proved woefully inadequate, incapable of receiving a clear signal more than a few floors above the ground. Only 20 minutes after the second jet slammed into the south tower, the chief realised there was no hope of bringing the fire under control and that the upper floors were in imminent danger of collapse. "I made the decision that so many things were going wrong, it was time to get our firemen out,'' he says. As it turned out, it took 40 minutes before the implosion of the south tower, from which not a single firefighter emerged alive. It is now clear almost none of them knew they had been ordered to leave.

The chief says it is easy to see, with hindsight, how the tragedy might have been avoided. Only four office workers below the impact of the two aircraft died in the disaster. The nearly 3,000 who perished were killed on impact or trapped beyond rescue on the upper floors. " But we didn' t know that when we went up," the chief says.

"When we arrived we knew there were people trapped in the building, people who were badly injured.''

There is no doubt their heroism saved hundreds. But it is also clear that if the firefighters had received the evacuation order - with the 40 minutes' grace - almost all of those who died could still be alive today.

Chief Callan knew when he tried to pull his men out that the radios were not working properly.

" If we had a better communication system, we would have been able to save a lot more firefighters," he says. He was still running the emergency command centre when the first tower collapsed. "My first thought was that another plane had landed in the street," he recalls. Soon he was running for his life - one of a group of 12 who made it to safety.

Almost as an afterthought, he reveals his three sons are firemen. "For four hours, I didn't know if they were in there or not." He then learned none had been on duty that morning.

The inquest about what went wrong that day continues. New radios have been ordered. "And if it happens again, we are going to send less people into the building," he says.

The chief ought to be thinking about retirement but hopes to serve a little longer. His is a department in crisis, hit by a flood of resignations and retirements in the wake of the disaster. And then there are the dead.

"We lost 4,400 years of collective experience in a single morning," he says. "You can't replace that.''