Question Silo Questions

[Notebook]

A couple of questions about this silo:-

http://www.spaceuk.org/bstreak/bs/k11.html

1) At the right-hand side of the vertical section diagram are descriptions pointing to the working platforms at various heights in the silo.
Two are called "Convection Seal Platform"
Why would it be neccesary to restict convection in the silo?

2) in the cross-section diagram of Level 3 there are 5 collimators.

The 5 lines converging onto the missile are light beams used to align the guidance system.

Any ideas how this is used. The beams are level with the lox tank, though there is a line pointing up into what would be Equipment Bay in the missile version.

All replies appreciated.

N.

 

[tblaxland]

1. Not real sure on this one but I can tell you from experience that buildings that have tall atriums in them (> about 5 stories) often require careful planning so that the temperatures at the top do not get too high (I just recently worked on one here, temperatures at the top get to about 70°C in summer, we designed in a ventilated inverted sump at the top so the hot air layer was above most of the building occupants). By putting convection barriers in, it could stop a large and high temperature hot air layer developing at around the warhead level.

2. The IMUs tend to drift relatively rapidly and the collimators are likely used to align the IMUs to a known good orientation shortly before the launch. The guidance system has sensors that can detect the beams from the collimators and can measure very accurately what direction they are coming from with respect to the local vessel frame. The ground side also knows the orientation of the collimators very accurately with respect to some inertial reference frame. Combine the two and you have a guidance system that then knows the vessel orientation with respect to the chosen inertial frame. In a similar vain, the stars are often used for aligning guidance systems once on orbit. The Apollo 8 Flight Journal makes mention of such a system here: http://history.nasa.gov/ap08fj/01launch_ascent.htm#iu.

 

[Notebook]

Thanks as always, I'll have a bit of research into that.

N.

---------- Post added at 09:34 ---------- Previous post was Yesterday at 17:43 ----------

All I can find on the missile guidance system is in the text on this page:-

http://i89.photobucket.com/albums/k207/Notebook_04/Europa.jpg

Picture is a bit confusing as it is the Europa multi-stage, not the missile variant.

The guidance and control of the Saturn V is achieved independently from the spacecraft by the Instrument Unit (IU) a one-meter ring atop the S-IVB stage. This contains its own computer, the LVDC (Launch Vehicle Digital Computer), and a gyroscopically stabilised platform, the ST-124. The platform is aligned prior to launch by rotating its X stable member with respect to a theodolite, located some distance down the crawlerway. A small window in the side of the IU allows the theodolite to view the platform. For this launch, the precise azimuth will be 72.124°.]

Sounds like they used the same idea in the silo.

They had trouble building the guidance system for BS, and eventualy used gyroscopes from a US compamy called Kearfort.

No silos were completed, but they did make a start near Woomera:-

http://i89.photobucket.com/albums/k207/Notebook_04/File0002-1.jpg

N.

 

[Urwumpe]

They had trouble building the guidance system for BS, and eventualy used gyroscopes from a US compamy called Kearfort.

Kearfort is building also the IMUs for the Space Shuttle. And will likely get the contract for the CEV, as specialist company.

 

[Notebook]

Good for them, I would have thought they'd have dissapeared into one of the big contractors.

N.

 

[Urwumpe]

Well, Kearfott (my fault) is effectivly owned by a company called Astronautics Corporation of America.

http://en.wikipedia.org/wiki/Astronautics_Corporation_of_America

 

[Notebook]

Not surprised somebody bought them, surprised they were part of BAE for a while.

I only know of them from a friend I drink with(very irregularly( He used to work for a company called Elliot Automation, and was there when they were developing the inertial guidance system for the TSR-2 strike aircraft. He moved into sales and marketing, says he wasn't a good engineer, but a better salesman! Sounds to me like he enjoyed the travelling.
They couldn't find a gyroscope in the UK that was good enough, and used the Kearfott product. They didn't have any involvement with Blue Streak he says, but they were involved with Blue Steel. He wasn't surprised that Kearfott name popped up, they were probably the best you could get at the time.

N.

 

[tblaxland]

No silos were completed, but they did make a start near Woomera:-

http://i89.photobucket.com/albums/k207/Notebook_04/File0002-1.jpg

Nice photo. I wonder what it looks like now. One day I'll get out there.

 

[Notebook]

Doubt if its changed much, maybe crumbled round the edges a bit. Hopefully fenced off, wouldn't like to stumble over that in the dark...

English Heritage, who look after bits of rock and stuff in .... England, got quite excited about this hole in the ground near the Spadeadam test site.

Google Earth 55.057409 -2.583909

They think its a bore hole for a K11 silo, they did start digging a hole in nineteen sixty and frozen to death, but nobody remembers where and the documents are still in the Public Records Office till they don't embarass anyone.

N.

 

[tblaxland]

Doubt if its changed much, maybe crumbled round the edges a bit. Hopefully fenced off, wouldn't like to stumble over that in the dark...

Well, if you fall in you shouldn't have been there... and it saves the RAAF the public embarrassment of having to announce they've shot someone.

They think its a bore hole for a K11 silo, they did start digging a hole in nineteen sixty and frozen to death, but nobody remembers where and the documents are still in the Public Records Office till they don't embarass anyone.

Oh well, more exciting than the Olde Sydney Towne porcelain tea cups they found on a building site I was on recently :dry:

 

[Notebook]

No Deviation, quite right....
N.