I don't think it's any kind of secret, but if you didn't know, these afternoon spots on KCRW are recorded ahead of time. A couple of hours ahead for me usually. Sometimes longer.

So I was in my car on the 405 just before this time slot last Friday when I heard Ken Borgers break in to programming with a news bulletin.

Two trains had collided on the tracks in Chatsworth, and the first reports -– and Ken's voice -- suggested a real calamity.

Just about everybody now knows what was unclear then, that the scene in Chatsworth was worse than anybody could have imagined.

Two trains -- traveling 40 miles an hour -- slamming head on with almost no warning on a blind curve. A mile away, people reported that a massive bomb had gone off.

Up close, of course, it was horrendous. Metrolink train #111 was full of people headed to Simi Valley and Moorpark. They got the worst of the impact.

The first good Samaritans to run toward the smoke plume found people moaning beside the tracks and hears screams from inside the commuter train. The lead car was on fire.

Emergency responders swarmed to the wreckage, and TV helicopters filled the sky, followed by rescue choppers. Forty patients were flown to trauma centers before the night was over.

It was late into the night before we all realized that the Metrolink engine had been shoved back into the front car. And that many of the passengers never got out.

Among them were LAPD officer Spree Desha, who rode the train home in uniform every day to help keep order. Maria Villalobos was coming home from her last class at the Fashion Institute in downtown LA.

Paul Long, a high school teacher, had just gotten back from burying his mother in South Carolina.

One of the passengers who died – and three among the injured – had survived the 2005 Metrolink crash in Glendale where a jilted lover parked his Jeep Cherokee on the tracks.

In this kind of incident, the heroes are numerous and the personal stories of tragedy and grief almost unbearable.

Going forward, it's the sidebars that many will remember, and that will begin to shape how this disaster is assigned to history.

The police honor guard as Officer Desha's remains were brought out of the mangled car. The family that reported receiving dozens of calls from the cellphone of the father and brother who died instantly in the crash.

The teenagers who say they were text messaging with the Metrolink engineer seconds before the collision.

And the honesty that cost Denise Tyrrell her job, but that may have brought a lot of clarity to the media chaos when it was needed most.

Tyrrell was the press spokeswoman for Metrolink who faced the cameras and went live on the air dozens of times during that terrible first night, and through the weekend.

I saw her being cautious at first, refusing even to call the crash a head-on, because enough wasn't known. By Saturday afternoon, she acknowledged the obvious – that for unknown reasons, the Metrolink train's engineer did not stop as required to let the freight train pass.

She had her boss's OK to give the statement, but the Metrolink agency's board threw a fit. It tried to back off on the mild admission, so Tyrrell felt stabbed in the back and resigned.

The National Transportation Safety Board also objected to Tyrrell's honesty policy. But Tyrrell's resignation letter was elegant in its plain speak:

"Although the NTSB is miffed," she wrote, "there is a very good reason for Metrolink to state that our engineer ran a red light - it was the truth."

She may not be exactly a hero of this tragedy, but Tyrrell does deserve our respect for being straight with the facts.

For KCRW, this has been Kevin Roderick with LA Observed.