Question: what are "those things" in this picture?

[dioditto]

http://www.fas.org/nuke/guide/usa/icbm/pk-pica.jpg

What are those "tile-looking" thing that falls off when LGM-118 Peacekeeper is launched?? Does anyone know?

Initially I thought it is tiles to protect the seperators between the stage rocket motors, but it doesn't look it after closer scrutiny since if that's the case the some stage rocket motor looks decidingly small or unprotected.

 

[Systems Adict]

Some one can correct me if I'm wrong, but they are I believe that they are "packing pieces".

These are inserted along with the missile, as it's placed into it's cannister, to help keep the missile centred during storage & operation & help to protect it from minor knocks during transport.

They are often made of thermally insulating materials to stop temperature variations/temperature transfer between the skin of the cannister/outside world and the missile.

This insulation stops extreme heat/cold from affecting the delicate circuitry of the guidance & control systems.


Systems Adict

 

[dioditto]

Some one can correct me if I'm wrong, but they are I believe that they are "packing pieces".

These are inserted along with the missile, as it's placed into it's cannister, to help keep the missile centred during storage & operation & help to protect it from minor knocks during transport.

They are often made of thermally insulating materials to stop temperature variations/temperature transfer between the skin of the cannister/outside world and the missile.

This insulation stops extreme heat/cold from affecting the delicate circuitry of the guidance & control systems.


Systems Adict

Correct me if I am wrong
If you look at the picture here :
http://en.wikipedia.org/wiki/Image:Peacekeeper_missile.jpg
Those "packing pieces" only covers sections of the missile.
So, if it's really for thermal protection, why is it only sections of it are covered with those?

 

[windscorpion]

maybe some parts of the missile need more protection than others

 

[rossfrb_1]

it's a little difficult to tell, but is the white portion right at the bottom of the image, part of the missile or a launch cannister? If the latter then packing pieces seems a reasonable guess - sort of like a sabot.

rb

 

[dioditto]

it's a little difficult to tell, but is the white portion right at the bottom of the image, part of the missile or a launch cannister? If the latter then packing pieces seems a reasonable guess - sort of like a sabot.

rb

I think the white piece at the bottom is part of the missile. LGM-118 is always silo based. (there was plan for rail based version but never got off the ground) So yeh, that white part is part of the missile body.

 

[Systems Adict]

Correct me if I am wrong

Those "packing pieces" only covers sections of the missile.
So, if it's really for thermal protection, why is it only sections of it are covered with those?

Firstly, in your original post you mentioned the sections / stages

The Missile is split into 3 sections. The Red & White stripes sections I BELIEVE are where the seperators (explosive charges between sections) are.

The lower stages in between MAY be filled with liquid fuel (I'm not sure whether the missile is solid or liquid fuelled).

The upper section is obviously where the war head(s) & most of the control equipment is.


If you go back to your 1st picture from the FAS site, you'll hopefully understand my comments, but I'll expand them anyway.



As I stated previously, the blocks are used as spacing material, they prevent outer skin of the missile touching the sides of the cannister, or any supportive equipment around the missile, such as mechanical arms that withdraw when the missile is launched.

As the missiles leaves it's silo / cannister, these are cast aside, to help the missile maintain a streamlined shape, for improved velocity.

From the two pictures, I would hazard a guess that the one on the FAS site is an early test shot, with the missile being launched from a cannister, whereas it's obvious from the 2nd picture it's being launched from a silo.

Cannisters generally travel on their sides, therefore inherintly will need more spacers to help support the missile & it's contents during movement.

Silo launched missiles are mounted vertically, with support mechanisims coming from the sides. The spacers would only be needed in the areas where the support arms come into contact with the missiles.

As for the thermal properties of the spacers, I mentioned this for 2 reasons.

#1. Due to the properties of liquid fuels, which tend to be at lower temperatures than the air around the missiles. Ambience of the surrounding air can compound this temperature effect also, helping increase the likelyhood of transference of these effects to the sensitive control equipment.

#2. To help cut down the weight, they are made of polystyrene, similar to the packing you find in boxes that TV's & other electronic equipment come in. It's robust enough, while being light & cheap !

Hope this helps.



...& sorry for stating the obvious, but it sometimes help to clear things up.

Systems Adict

 

[hybrid]

Firstly, in your original post you mentioned the sections / stages

The Missile is split into 3 sections. The Red & White stripes sections I BELIEVE are where the seperators (explosive charges between sections) are.

The lower stages in between MAY be filled with liquid fuel (I'm not sure whether the missile is solid or liquid fuelled).

The upper section is obviously where the war head(s) & most of the control equipment is.


If you go back to your 1st picture from the FAS site, you'll hopefully understand my comments, but I'll expand them anyway.



As I stated previously, the blocks are used as spacing material, they prevent outer skin of the missile touching the sides of the cannister, or any supportive equipment around the missile, such as mechanical arms that withdraw when the missile is launched.

As the missiles leaves it's silo / cannister, these are cast aside, to help the missile maintain a streamlined shape, for improved velocity.

From the two pictures, I would hazard a guess that the one on the FAS site is an early test shot, with the missile being launched from a cannister, whereas it's obvious from the 2nd picture it's being launched from a silo.

Cannisters generally travel on their sides, therefore inherintly will need more spacers to help support the missile & it's contents during movement.

Silo launched missiles are mounted vertically, with support mechanisims coming from the sides. The spacers would only be needed in the areas where the support arms come into contact with the missiles.

As for the thermal properties of the spacers, I mentioned this for 2 reasons.

#1. Due to the properties of liquid fuels, which tend to be at lower temperatures than the air around the missiles. Ambience of the surrounding air can compound this temperature effect also, helping increase the likelyhood of transference of these effects to the sensitive control equipment.

#2. To help cut down the weight, they are made of polystyrene, similar to the packing you find in boxes that TV's & other electronic equipment come in. It's robust enough, while being light & cheap !

Hope this helps.



...& sorry for stating the obvious, but it sometimes help to clear things up.

Systems Adict

The Peacekeeper missile as pictured here was a solid fuel missile with a fourth stage hypergolic.

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

 

[dioditto]

Systems Adict, thanks for the explaination