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View Full Version : What's the deal with the SRB cams?



Glom
2009-Jul-21, 07:41 PM
I just watched the SRB cam footage. The rear and forward cameras are as you would imagine. You start with rocket sound. Everything then goes silent as you get into SPAAACE, but then there's no return of sound. The forward cam gets all kinds of crud on it.

The intertank cams are weird. There is sound throughout, albeit a lonely metal clinking sound while in SPAAACE. It starts with the rather uninspiring view of a closeup of the ET until separation. Close to splashdown, everything goes dark for a short while and then we're looking up at the chutes.

So questions:
1) How did the intertank cam get from the side to the top?
2) Why does the forward cam get all this gunk on it?
3) Why is there only partial sound on the forward and rear while full sound on the intertank?

Papa Surf
2009-Jul-21, 10:26 PM
I enjoy watching these cam's videos. I don't have the answers you seek but just my observations.
I like how, after the SRBs separate and begin the slow tumble back to earth there is that ominous groaning of, I presume, the rockets outer hull. The sound gets transfered to the camera internally. I also noticed an oscillating wind noise. Finally the cables from the chutes rapping against the hull after splashdown. Fun ride.

GeorgeLeRoyTirebiter
2009-Jul-21, 11:57 PM
So questions:

Some speculation:

1) How did the intertank cam get from the side to the top?
The timing of this corresponds with the nose cap ejection and deployment of the pilot chute. The intertank camera appears to be mounted at the base of the parachute compartment (the conical part of the SRBs line up with the intertank in the assembled stack). I would guess that there's some sort of linkage or pyrotechnic doodad that rotates the camera when the cap comes off, in order to get video of the parachute deployment.

2) Why does the forward cam get all this gunk on it?
Even after burnout, the SRBs are still spitting out smoke and burning chunks of fuel. The boosters tumble after separation, and the forward camera just happen to be in the part of the booster that passes through this plume. You can see this in the intertank cameras by watching the other booster just after separation; the stream of glowing bits hits the forward part of the booster.

3) Why is there only partial sound on the forward and rear while full sound on the intertank?
The intertank cameras may be the only ones with microphones.

CJSF
2009-Jul-22, 04:37 AM
Some speculation:

1) How did the intertank cam get from the side to the top?
The timing of this corresponds with the nose cap ejection and deployment of the pilot chute. The intertank camera appears to be mounted at the base of the parachute compartment (the conical part of the SRBs line up with the intertank in the assembled stack). I would guess that there's some sort of linkage or pyrotechnic doodad that rotates the camera when the cap comes off, in order to get video of the parachute deployment.


Also, the cameras have really wide-angled lenses.

CJSF