|
|
|
|
Author
|
Topic: Saturn V staging
|
Paul78zephyr
Member Posts: 678
From: Hudson, MA
Registered: Jul 2005
|
posted 05-02-2006 07:48 AM
  
I recently watched some footage of Saturn V launches and there is some very good long range camera footage of the S-1C seperation and S-II ignition. It looks like a very violent episode. I can slow down the DVD to allow up to 1/32 slow motion and the staging seems to be so 'explosive' enveloping almost the entire vehicle in a fireball, but lasting only a few seconds even at this speed (so in real time the staging is probably less than a second). I cannot tell if its the seperation of the stages themselves, or the S-II ignition or what. Also in the 15 seconds or so leading up to the staging the S-IC thrust trail expands enormously and there seems the be a 'following' plume behind the main expanding plume - is this shockwave of sorts?Thanks,
Paul [This message has been edited by Paul78zephyr (edited May 02, 2006).] |
divemaster
Member Posts: 1376
From: ridgefield, ct
Registered: May 2002
|
posted 05-02-2006 09:11 AM
Commonly referred to as "the great train wreck".From memory [and I'm sure there are those out there that will correct me on this], you had four "controlled explosions" happening within a very short time:
Explosive bolts/primer cord going off to seperate the two stages
Firing of the interstage ullage motors
Firing of the SIC retros to put distance between the two stages
Ignition of the SII engines
Lots of fire in a very short time. There were also some bizarre camera angles due to distance and the effect of telephoto lenses. As I recall, there was a discussion on this board awhile back talking about an Apollo 11 photo where it looks like the entire SIC stage is enveloped in flames. It was the camera angle.
|
Blackarrow
Member Posts: 3160
From: Belfast, United Kingdom
Registered: Feb 2002
|
posted 05-03-2006 05:49 PM
There is another feature of the S1C/SII staging which looks really alarming on close-up filming: shortly before staging, it looks as if flames ride up the sides of the SIC. This even looks like it causes scorching and blackening of the paintwork at the bottom of the stage. Was that a real phenomenon or just an optical illusion? This is definitely visible before the ullage rockets or retro-rockets fire. |
divemaster
Member Posts: 1376
From: ridgefield, ct
Registered: May 2002
|
posted 05-09-2006 10:50 AM
I think the "scorching" was, in fact, an optical illusion due to camera angles and the effect of telephoto lens distortion.However, being the hardware junkie that I am, to paraphrase a couple of items from Alan Lawrie's book "Saturn": Fin Fairings: Each of the eight retrorockets enclosed in the fairings generates 86,600 pounds of thrust for 2/3 of a second, blowing off the tips of the fairings. Since these need to slow the ascent of the first stage, they would need to fire against the direction of travel, effectively, "up" the sides of the first stage Ordnance System: A linear shaped charge utilizing exploding bridge-wire initiators physically severs the two stages. Kaboom! See pages 24, 48 and 61 of this book for complete descriptions. | |
Contact Us | The Source for Space History & Artifacts
Copyright 2020 collectSPACE.com All rights reserved.
Ultimate Bulletin Board 5.47a
|
|
|
 advertisement
|
