Spacelog Apollo 8

Apollo 8, Houston. Say again.

The S-IVB is really venting.

Roger. Understand; that is supposedly a non-propulsive vent. The big blowdown maneuver, it starts maneuvering to blowdown attitude at 04:44:55, and the vent occurs at 05:07:55.

05:07:55.

Roger.

That is the nonpropulsive vent, but it's pretty spectacular. It's spewing out from all sides like a huge water sprinkler.

Roger. Get some pictures of it.

We are.

Say again that big vent time, so I can write it down please, Houston.

Roger. Big vent time 05:07:55, and it will start maneuvering to vent attitude beginning at 04:44:55. Bill has got the tape recorder back.

Thank you. Roger.

We're receiving VHF music now, Houston. Thank you.

Yes, you took the words right out of my mouth, Frank, and we would like to know also how far away from the S-IVB you are now.

I guess we are between 500 to 1000 feet.

Roger.

Herb Alpert seems pretty good.

Houston, Apollo 8.

Apollo 8, Houston.

Roger. I believe we are going to have to vent or thrust away from this thing; we seem to be getting closer.

Roger. Understand, Frank; go ahead whenever—just give us some idea of when you did it and how much.

Roger.

You are loud and clear, Mike. Go ahead.

Okay, Frank. On your additional separation maneuver, we recommend that you make a radial burn, point your plus X-axis toward the earth, and thrust minus X for 3 feet per second. Over.

I don't want to do that; I'll lose sight of the S-IVB.

Okay. The reason we want a radial burn is to increase your midcourse correction so we can use the SPS. Stand by on it.

Apollo 8, Houston.

Go ahead.

How close to a radial burn can you get without losing sight of the S-IVB, Frank?

Well, I don't know because I can't see the earth now, Mike.

Okay.

We can pitch down some. Jim has the earth in the optics so we could pitch some and get pretty close to one, I guess.

Apollo 8, Houston.

Go ahead, Houston. Apollo 8.

We can give you a pitch gimbal angle on radial direction if that would be a help. It's 181 degrees; pitch gimbal angle would be exactly radial at 4 hours and 10 minutes. I don't know whether that solves your visibility problem or not.

181?

That's affirmative.

Well, then zero would be just as good, wouldn't it?

Frank, if you use zero, then make the SEP if possible in the plus X thrusters. That's the direction of the burn we'd like.

Well, can't do that. I'll thrust right square into that S-IVB.

Yes, okay. Understand.

What will he maneuver to as far as the gimbal angle for his blowdown?

Apollo 8, Houston. At blowdown, that S-IVB should be oriented to perform a retrograde blowdown along the local horizontal.

Okay.

Is it still chasing? Does it look like it is closing on you, Frank?