Listening to the mission control audio loops on Apollo In Real Time in the immediate aftermath of the Apollo 13 explosion, I hear flight director Kranz asking about "delogs":
056:26:01 FLIGHT EECOM, from FLIGHT. 056:26:02 EECOM FLIGHT, EECOM. 056:26:03 FLIGHT Have you got anybody getting a delog on this thing downstairs? 056:26:07 FLIGHT NETWORK, from FLIGHT. 056:26:09 NETWORK FLIGHT, NETWORK. 056:26:10 FLIGHT Bring me up another computer in the RTCC, will you? 056:26:14 NETWORK We got one machine on the RTCC and we got dual CPs downstairs. 056:26:18 FLIGHT Okay, I want another machine up in the RTCC and I want a bunch of guys capable of running delogs down there. 056:26:23 NETWORK Roger that.
From the context I assume it might be something to do with reviewing telemetry data, but I have never come across the term "delog" in my Apollo studies before.
Kranz keeps returning to the topic:
056:40:59 FLIGHT Okay, now has anybody started the delog of the initial problem? You've got a delog going? Have you got people that are going to be in a position to evaluate it?
056:44:29 FLIGHT EECOM, I don't think we're going to come to any solution here until we get back to the initial set of conditions, so I hope you got a set of guys looking at the delog pretty soon.
At the shift change, with Kranz's team handing off to Glynn Lunney's, he mentions the delogs again:
057:06:12 FLIGHT Okay. All flight controllers, I'm handing over to Glynn. I assume the majority of all the team guys are pretty much briefed and up to speed as best we can. Now what I'd suggest is the white team do two things: they go over the delogs - okay - let me go back over this again. We're handing over to Glynn. I'd suggest the white team goes back and starts going through the delog of the data. In other words, let's see if we can go back to the initial conditions and work on that problem to see if we can find out what happened and we may find some better clues as to what to do and let the fresh guys come on and try to figure out where do we go from here. 057:06:51 FLIGHT And the delog is in way now. Roger.
What's a delog, and why is Gene Kranz concerned with it half an hour after the explosion?