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Fred22

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My next project will be a scratch built minuteman. I thought it might be interesting to build a scale silo to launch it from :) Has anyone done this before or have any suggestions?
Thanks
Fred
 

ONAWHIM

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How about a tower launcher, 3-rail or 3-rod?
Place the "silo" over it to hide it.

Wm.
 

ONAWHIM

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Additional thought...


Why not build a cut-away silo complete with modeled umbilical retracts, muzzle swing-away door, etc.

random thoughts...
 

mperdue

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My next project will be a scratch built minuteman. I thought it might be interesting to build a scale silo to launch it from :) Has anyone done this before or have any suggestions?
Thanks
Fred
I worked on Minuteman III with I was in the USAF. Please post photos of your progress on this project.

Mario

PS

Never launch a rocket from the 11 foot deep section of a public swimming pool - especially if there is a very large woman wading in the shallow end of the same pool. Trust me on this one...
 

Pem Tech

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I worked on Minuteman III with I was in the USAF. Please post photos of your progress on this project.

Mario

PS

Never launch a rocket from the 11 foot deep section of a public swimming pool - especially if there is a very large woman wading in the shallow end of the same pool. Trust me on this one...

Hey Mario, I didn't know you worked in a silo. ANy details, photos or interesting bits of info would be appreciated. We had Titan II silos here in Arkansas, two of which blewup, I believe. Building a detailed silo to launch the rocket from is a great idea.
 

Bravo52

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Hey Mario, I didn't know you worked in a silo. ANy details, photos or interesting bits of info would be appreciated. We had Titan II silos here in Arkansas, two of which blewup, I believe. Building a detailed silo to launch the rocket from is a great idea.
Don't you mean they "Bload up"........ ;)
 

Fred22

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I worked on Minuteman III with I was in the USAF. Please post photos of your progress on this project.

Mario

PS

Never launch a rocket from the 11 foot deep section of a public swimming pool - especially if there is a very large woman wading in the shallow end of the same pool. Trust me on this one...
Im going to in the scale section. Any advice would be greatly apreciated :) Reat assure I will avoid pools and bigger folks when I launch :)
Cheers
fred
 

Fred22

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I was thinking of a simple box pattern put in a hole then launch. detail the top maybe with a working hatch:) Biggest problem I see is exhaust crisping the rocket. I was wondering if a water tray would help or would it just steam said rocket?
Cheers
Fred
 

luke strawwalker

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My SS-17 and Minuteman III scratchbuilds over in the archives were designed for silo launch.

I actually launched the SS-17 from an actual in-ground silo once, though it was a test launch, not 'real'.

I used a hand post-hole digger to auger a hole about 3 feet deep in the backyard. I put concrete stepping stones on either side for 'silo doors' and pushed a launch rod down a couple inches in the clay at the bottom of the 'silo'.

For the test launch, I put a 1/2A6-2 in the rocket (designed for "D" motors) and installed the ignitor, hooked up the launch clips, and slid it down the rod into the silo. Then I launched it. It popped up out of the silo about 3 feet in the air, neatly laid over into the grass, and promptly popped it's 'chute'.

Kinda neat... I never got around to launching it 'for real' because it was about the time I started mechanic's school and got out of rocketry, and the rain collapsed the 'silo' before I could launch again.

I also made a 'revetment launcher' out of window screen stapled to a plywood square and covered with plaster of paris. This was basically a curved "mountain" like you might build for a model-railroading type layout, but portable on a plywood 2 foot-ish square, with a flat metal blast deflector under the 'launch pad' and a hole drilled for the launch rod. It looked pretty good-- flew my Alpha III off it a number of times.

I also made a plywood 'launch pad' similar to a stylized version of the ones at the Cape, with a 'flame tunnel' lined with steel on bottom, and a round hole in the top where the rocket sat over the 'flame pit' It worked pretty well and looked kinda neat. I'd even use a bit of masking tape rolled back on itself to tape a string 'umbilical' to the rocket very lightly before liftoff... still have videos of that one. I'd also load up the 'flame tunnel' with all-purpose flour so the engine jet gave a bit 'smoke cloud' at liftoff (though I wouldn't advise that anymore-- dust explosions would be bad).

I don't think I have pics of any of those anymore but the "Cape style" launcher-- if I do they're buried in my high school era junk somewhere.

Nowdays I launch everything off my clone of Dr. Zooch's "Pad 34Z" (Z for Zooch) that is detailed back in the archives and is visible in my build threads 'glamour shots' pics at the ends.

Later and good luck! OL JR :)

PS. I had planned to one day build a "portable silo" using a toilet flange and 4 inch PVC pipe and pipe cap from the lumberyard, centered in a plywood 'table' that could be either A) a cheap 'card table' bought cheap at a yard sale, B) set up between two sawhorses, folding chairs, or tables, or C) have four legs attached to it so it's free standing. I'd drill the bottom cap for the launch rod. Post pics! :D
 

n5wd

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My next project will be a scratch built minuteman. I thought it might be interesting to build a scale silo to launch it from :) Has anyone done this before or have any suggestions?
I II or III? There are some good illustrations of a Minuteman II complex floating around on the web, a couple of the pix of which I think are mine, taken while I was with the PAO at the 321st Strat Missile Wing at Grand Forks.
 

luke strawwalker

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I was thinking of a simple box pattern put in a hole then launch. detail the top maybe with a working hatch:) Biggest problem I see is exhaust crisping the rocket. I was wondering if a water tray would help or would it just steam said rocket?
Cheers
Fred
The rocket shouldn't be in the "silo" long enough to "crisp" it I would think. Maybe a little discoloration around the base, but that should be it I would think.

If you're worried about it, depending on how you're building it, I can think of two solutions immediately.

1) If you're using a PVC pipe/toilet flange top (they're slightly conical in shape, like a lot of silos (especially Russian) then instead of installing a 4 inch pipe cap at the bottom, install a PVC bell reducer down to 1.5 inch or 1 inch pipe, and duct it back to the 'surface' for a realistic 'blast vent' as many of the silos had (Titan II and Atlas anyway-- Minuteman's were 'fire in the hole' silos without flame tunnels, since they were solid-fuelled and much more robust, less susceptible to damage from engine acoustics or blast than were the thin-skinned Titan and Atlas missiles)

2) if your using something else, install a blast deflector and 'standoff' below the rocket to give more room for the engine exhaust to expand and cool before it rises up around the rocket. This would be the most realistic for a Minuteman, BTW, for reasons cited above.

Sounds cool. Later! OL JR :)

PS... my SS-17 had a 'fin can' that slid up over the motor mount and into the rear body of the rocket, with the clear fins sticking out 'underneath' and out to the sides of the rocket in flight configuration-- when I "silo fired" it they came out perfectly fine-- maybe a TINY bit of 'smoke staining' that easily wiped off. BUT that was with a VERY small motor on a 'test launch' as well...
 

MarkII

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I was thinking of a simple box pattern put in a hole then launch. detail the top maybe with a working hatch:) Biggest problem I see is exhaust crisping the rocket. I was wondering if a water tray would help or would it just steam said rocket?
Cheers
Fred
Oh, Fred, you are going to HAVE to launch it from a hole in the ground, now. None of this above-ground pseudo-silo business; if you are going to go to the trouble, it POSITIVELY HAS TO BE launched from underground. :bangbang:

You could, I suppose, create flame trenches that vented upward to the surface next to the launch hole, but angling away from it. Isn't that how it worked with the real ones?

EDIT: But make sure, of course, that you clear away any flammable vegetation from around your silo, too.

Protecting your model from being scorched would no doubt be easier if you went with the above-ground pseudo-silo. You could go completely non-scale with the subterranean section, and just have a tower that is open all around the rocket, topped by a make-believe "ground level" landscape. As someone already mentioned, the landscape could be done on a sheet of plywood that you could just lay across a couple of sawhorses, with your launch tower set up below it. The exhaust would just vent out of the open sides of the tower, and you would have a blast deflector right below it to protect the ground. I mean, you could go that way... :rolleyes:

You could also build a self-contained silo with branching flame trenches as I previously described. You could make it all one piece that you could transport to a location and set up. It would be great in the winter because you could just take to to your launch site, sink it down into the snow and then fill the spaces around it with more snow. :D In the warm weather, you could do the same thing, temporarily burying it at a beach, a sandpit or a sandbox. ;)

EDIT II: I'm not so sure that using a tray containing water as a blast deflector/burn protector would actually work. I would imagine that when the jet hit the water, it would just cause it to splash upward, getting the bottom of your rocket wet. I doubt that the splash would extinguish the motor, but it could cause other problems.

MarkII
 
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Fred22

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My SS-17 and Minuteman III scratchbuilds over in the archives were designed for silo launch.

I actually launched the SS-17 from an actual in-ground silo once, though it was a test launch, not 'real'.

I used a hand post-hole digger to auger a hole about 3 feet deep in the backyard. I put concrete stepping stones on either side for 'silo doors' and pushed a launch rod down a couple inches in the clay at the bottom of the 'silo'.

For the test launch, I put a 1/2A6-2 in the rocket (designed for "D" motors) and installed the ignitor, hooked up the launch clips, and slid it down the rod into the silo. Then I launched it. It popped up out of the silo about 3 feet in the air, neatly laid over into the grass, and promptly popped it's 'chute'.

Kinda neat... I never got around to launching it 'for real' because it was about the time I started mechanic's school and got out of rocketry, and the rain collapsed the 'silo' before I could launch again.

I also made a 'revetment launcher' out of window screen stapled to a plywood square and covered with plaster of paris. This was basically a curved "mountain" like you might build for a model-railroading type layout, but portable on a plywood 2 foot-ish square, with a flat metal blast deflector under the 'launch pad' and a hole drilled for the launch rod. It looked pretty good-- flew my Alpha III off it a number of times.

I also made a plywood 'launch pad' similar to a stylized version of the ones at the Cape, with a 'flame tunnel' lined with steel on bottom, and a round hole in the top where the rocket sat over the 'flame pit' It worked pretty well and looked kinda neat. I'd even use a bit of masking tape rolled back on itself to tape a string 'umbilical' to the rocket very lightly before liftoff... still have videos of that one. I'd also load up the 'flame tunnel' with all-purpose flour so the engine jet gave a bit 'smoke cloud' at liftoff (though I wouldn't advise that anymore-- dust explosions would be bad).

I don't think I have pics of any of those anymore but the "Cape style" launcher-- if I do they're buried in my high school era junk somewhere.

Nowdays I launch everything off my clone of Dr. Zooch's "Pad 34Z" (Z for Zooch) that is detailed back in the archives and is visible in my build threads 'glamour shots' pics at the ends.

Later and good luck! OL JR :)

PS. I had planned to one day build a "portable silo" using a toilet flange and 4 inch PVC pipe and pipe cap from the lumberyard, centered in a plywood 'table' that could be either A) a cheap 'card table' bought cheap at a yard sale, B) set up between two sawhorses, folding chairs, or tables, or C) have four legs attached to it so it's free standing. I'd drill the bottom cap for the launch rod. Post pics! :D
Sounds like a lot of good research and testing:) No problems with frying the rockets tail end in the three foot hole? PVC pipe sounds conveniant as I was just going to detail the top. I was thinking about an 18mm engine. Heres my scale data. The site has all kinds of good info on Minuteman :)
https://www.captainswoop.com/icbm/msls.html
Thanks for the info:)
Cheers
fred
 

Fred22

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I II or III? There are some good illustrations of a Minuteman II complex floating around on the web, a couple of the pix of which I think are mine, taken while I was with the PAO at the 321st Strat Missile Wing at Grand Forks.
I was thinking three but I would love to see your pictures please:)
Cheers
fred
 

sylvie369

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We had Titan II silos here in Arkansas, two of which blewup, I believe. Building a detailed silo to launch the rocket from is a great idea.
I find the juxtaposition of those two sentences rather disturbing. :cool:
 

luke strawwalker

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Oh, Fred, you are going to HAVE to launch it from a hole in the ground, now. None of this above-ground pseudo-silo business; if you are going to go to the trouble, it POSITIVELY HAS TO BE launched from underground. :bangbang:

You could, I suppose, create flame trenches that vented upward to the surface next to the launch hole, but angling away from it. Isn't that how it worked with the real ones?

MarkII
Only on Titan I, Titan II, and Atlas... those were liquid fuelled and the acoustics of the engines firing up and coming up to thrust, along with whatever 'detritus' in the bottom of the silo might be kicked up by the blast and puncture the fuel tanks. Remember one Titan II was punctured by a large socket wrench dropped from an upper work platform that bounced off the wall of the silo and perforated the skin of the fuel tank. If a glancing blow could perforate the missile, imagine what a stray bolt or nut or other debris in the bottom of the silo blown upward by the engine blast could do?? NASA takes some extraordinary measures to ensure their rockets don't disintegrate on the pad from the acoustics alone-- and that's OUT IN THE OPEN! Imagine the acoustics of the engine blast IN AN ENCLOSED SILO, echoing off the walls into the sides of the missile from ALL SIDES!

The bad thing about this was, the "blast tunnels" for the engine exhaust had to be cut as well, and had to have blast doors installed to protect the missile from nearby nuclear strikes-- otherwise the nuclear blast could simply funnel down the exhaust ports and demolish the missile from underneath (pressure waves rupturing the fuel tanks). This added greatly to the difficulties and expense in constructing the silos, and added a lot to their vulnerability to preemptive attack.

Minuteman was a SOLID FUEL missile, and so much more robust from an acoustics standpoint, so they were simply launched by "fire in the hole". The silo was basically a simple hole with a hard stand at the bottom that the missile sat on. Ever notice in those Minuteman launch vids, how the door opens, a HUGE flare of flame bursts straight up from the silo, and then the missile rises out of the flames, trailing licking flame and smoke before racing away, usually through a really 'cool looking' smoke ring?? That's "fire in the hole". The smoke ring is caused by the blast coming up ALL AROUND the missile as it lifts off from the silo.

Another thought just occurred-- how about that cardboard 'Readi-tubes' used for concrete?? Those are bigger than PVC, cheaper, and would work just as well... (for a portable silo anyway). Gotta be big enough diameter silo for the fins on the missile to fit down it!

Later! OL JR :)
 

MarkII

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Minuteman was a SOLID FUEL missile, and so much more robust from an acoustics standpoint, so they were simply launched by "fire in the hole". The silo was basically a simple hole with a hard stand at the bottom that the missile sat on. Ever notice in those Minuteman launch vids, how the door opens, a HUGE flare of flame bursts straight up from the silo, and then the missile rises out of the flames, trailing licking flame and smoke before racing away, usually through a really 'cool looking' smoke ring?? That's "fire in the hole". The smoke ring is caused by the blast coming up ALL AROUND the missile as it lifts off from the silo.
I can't say that I have actually ever seen videos of any of the rockets that you mentioned being launched out of their silos, nor have I ever seen anything other than a very schematic diagram of any of their silos (and that was just for the Atlas). I was just guessing about the flame tunnels. The Soviets used them for their N-1 (which of course was launched from the surface, but the flames went into a hole in the ground and then vented back up at an angle at the surface).

MarkII
 

MarkII

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Another thought just occurred-- how about that cardboard 'Readi-tubes' used for concrete?? Those are bigger than PVC, cheaper, and would work just as well... (for a portable silo anyway). Gotta be big enough diameter silo for the fins on the missile to fit down it!

Later! OL JR :)
The Minuteman didn't have fins, right? (But your model will need them.) I wonder how small of a span you could get away with?

Interesting design. Question: Was a silo ever meant to fire more than one missile in its service life? (IOW, did the USAF ever think that there would be more than one volley of missiles fired during Armageddon?)











Sliding silo cover....



The air vents are visible in the foreground in this photo.





MarkII
 
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mperdue

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I can't say that I have actually ever seen videos of any of the rockets that you mentioned being launched out of their silos, nor have I ever seen anything other than a very schematic diagram of any of their silos (and that was just for the Atlas). I was just guessing about the flame tunnels. The Soviets used them for their N-1 (which of course was launched from the surface, but the flames went into a hole in the ground and then vented back up at an angle at the surface).

MarkII
Try this link https://www.youtube.com/watch?v=2aHpqqhaHJ0

FWIW, the missile is actually suspended in a cage-like assembly that is adjustable so it can be precisely positioned. There are no channels to allow the fire to escape; the flames exit from the main opening just like the missile does. The missile is coated with a layer of cork to protect it from the heat until it clears the silo. The equipment in the silo has no such protection so it's a one-shot deal.

The door that you see opening weighed 90 tons when I was in the AF but it was upgraded to 120 shortly thereafter. Opening it as fast as they do is no small feat.

I didn't get out to the silos very often because I worked in the Electronics Lab. My job was to repair any of the electronic sub-systems used by the vehicle or the ground support equipment. The guidance system was very cool.

Also, Minuteman was only mostly solid propellant. The final stage, the PSRE (pronounced pisser) for "Propulsion System, Rocket Engine", used liquid fuel.

Mario
 
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Fred22

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I saw a J-class rocket launched from a "silo" years ago, I think by the vendor RocketSilo. There may have been a photo of it in Extreme Rocketry.

At the last Plaster Blaster, a team from Arizona launched four Patriots from a scale launch container.
Never even seen a J but that sounds very cool :)
Cheers
Fred
 

Fred22

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Only on Titan I, Titan II, and Atlas... those were liquid fuelled and the acoustics of the engines firing up and coming up to thrust, along with whatever 'detritus' in the bottom of the silo might be kicked up by the blast and puncture the fuel tanks. Remember one Titan II was punctured by a large socket wrench dropped from an upper work platform that bounced off the wall of the silo and perforated the skin of the fuel tank. If a glancing blow could perforate the missile, imagine what a stray bolt or nut or other debris in the bottom of the silo blown upward by the engine blast could do?? NASA takes some extraordinary measures to ensure their rockets don't disintegrate on the pad from the acoustics alone-- and that's OUT IN THE OPEN! Imagine the acoustics of the engine blast IN AN ENCLOSED SILO, echoing off the walls into the sides of the missile from ALL SIDES!

The bad thing about this was, the "blast tunnels" for the engine exhaust had to be cut as well, and had to have blast doors installed to protect the missile from nearby nuclear strikes-- otherwise the nuclear blast could simply funnel down the exhaust ports and demolish the missile from underneath (pressure waves rupturing the fuel tanks). This added greatly to the difficulties and expense in constructing the silos, and added a lot to their vulnerability to preemptive attack.

Minuteman was a SOLID FUEL missile, and so much more robust from an acoustics standpoint, so they were simply launched by "fire in the hole". The silo was basically a simple hole with a hard stand at the bottom that the missile sat on. Ever notice in those Minuteman launch vids, how the door opens, a HUGE flare of flame bursts straight up from the silo, and then the missile rises out of the flames, trailing licking flame and smoke before racing away, usually through a really 'cool looking' smoke ring?? That's "fire in the hole". The smoke ring is caused by the blast coming up ALL AROUND the missile as it lifts off from the silo.

Another thought just occurred-- how about that cardboard 'Readi-tubes' used for concrete?? Those are bigger than PVC, cheaper, and would work just as well... (for a portable silo anyway). Gotta be big enough diameter silo for the fins on the missile to fit down it!

Later! OL JR :)
God and i thought my kids stero was loud :) I will check the ready tubes as well. Im thinking a tube with a top platform attached. I will put in a tube in the side to run ignition wires and a blast plate. I suspect I will used a fixed blast plate with say 6 inches of space inderneath to allow the exhast to cool. KISS is very much alive and well for me. Now i just gotta get out the abacus and start figuring numbers :)
Cheers
fred
 

Fred22

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The Minuteman didn't have fins, right? (But your model will need them.) I wonder how small of a span you could get away with?

Interesting design. Question: Was a silo ever meant to fire more than one missile in its service life? (IOW, did the USAF ever think that there would be more than one volley of missiles fired during Armageddon?)

MarkII
I read there were some thoughts around reloading silos but I dont know how far it went. Thanks for the pictures and diagrams:) I was thinking about building a detailed top piece with hatches and things :) May have to go with 24mm as well :). I like the snow idea but by the time i get this build dirt will be the way to go but next year maybe:)
Cheers
fred
 

Fred22

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Try this link https://www.youtube.com/watch?v=2aHpqqhaHJ0

FWIW, the missile is actually suspended in a cage-like assembly that is adjustable so it can be precisely positioned. There are no channels to allow the fire to escape; the flames exit from the main opening just like the missile does. The missile is coated with a layer of cork to protect it from the heat until it clears the silo. The equipment in the silo has no such protection so it's a one-shot deal.

The door that you see opening weighed 90 tons when I was in the AF but it was upgraded to 120 shortly thereafter. Opening it as fast as they do is no small feat.

I didn't get out to the silos very often because I worked in the Electronics Lab. My job was to repair any of the electronic sub-systems used by the vehicle or the ground support equipment. The guidance system was very cool.

Also, Minuteman was only mostly solid propellant. The final stage, the PSRE (pronounced pisser) for "Propulsion System, Rocket Engine", used liquid fuel.

Mario
Sounds like an interesting job:) Was it a missile squadron that had warsaw pact furnace company as it's logo or was that aircraft:)
Cheers
fred
 

aerostadt

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I digress a little bit. The Peace Keeper (PK) actually has a solid propellant charge that fires into a small water reservoir to create steam (steam/gas generator). There is a lip seal on the side of the PK that makes a good enough seal that the steam ejects the missile from the silo. Once clear of the silo the PK is ignited like a submarine launched missile. An advantage of this method is that the silo can be re-loaded with another PK quickly without much refurbishment. The Russians use the same idea for their solid ICBM's.

Bob
 

luke strawwalker

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Sounds like a lot of good research and testing:) No problems with frying the rockets tail end in the three foot hole? PVC pipe sounds conveniant as I was just going to detail the top. I was thinking about an 18mm engine. Heres my scale data. The site has all kinds of good info on Minuteman :)
https://www.captainswoop.com/icbm/msls.html
Thanks for the info:)
Cheers
fred
Nope, no problems at all... maybe some "slight staining" from smoke on the plexi fins, nothing else.

I don't know how much the damp clay earth cooled the exhaust, but I doubt it was a whole lot, relatively speaking. The exhaust gases from our engines cool fairly decently just by expansion and mixing with ambient air, which the silo would be full of. By the time the exhaust flame streams out, hits the deflector (heating it up and cooling the gases), spreads out across the deflector, and starts curving back up again, it's had a LOT of mixing and time to cool, much like an ejection baffle. So long as your rocket isn't sitting 1/2 inch above the silo 'floor' and has more than 1/2 inch of clearnance all the way around (which would be necessary for the fin span I would think) it should be fine. If in doubt, give yourself a little greater 'depth' to the silo actually below the rocket, to give a greater air volume below the rocket for the exhaust to mix with, and a little more 'time/distance' for the exhaust gases to travel before they start back up around the rocket.

I only had a few grainy pictures to go by from Bill Gunston books we had in our high school library back when I built mine-- so I had to 'scale from photographs'... get one measurement you know (diameter from the text is a good one, or overall length) and then using dividers and an drafting scale, measure out every point in the picture, then plug the measurements into a 'scaling factor' derived from the ratio of the pic measurement of length or diameter to the real thing. Of course this doesn't account for perspective, so there is some error in this method, especially on shots where the rocket is not precisely 90 degrees to the camera. Small image size also reduces the "fidelity" of the data, since the greater the 'scaling ratio', the more 'unsure' the measurements are (more uncertainty) Close up photos, however, usually suffer more from perspective changes, especially on long tall objects like rockets... the camera *might* be close to perpendicular to the bottom third of the rocket, but the upper 2/3 might be at a significant angle (30-40-50 degrees or more) to the camera and that introduces SIGNIFICANT perspective errors, especially in length measurements. Diameters are less affected, but they DO develop errors due to perspective effects... (railroad tracks coming together in the distance though they are parallel).

Much MUCH easier scaling from drawings... :)

Good luck! OL JR :)

PS. That reminds me of one of the other methods that was employed by the Atlas missile-- COFFIN LAUNCHERS! These were steel and concrete structures with steel doors on top for a roof, in which the missile was stored horizontally in a cradle. To launch, the missile doors were opened, then the missile was stood upright, the cradle retracted, and the missile was fuelled and launched. VERY susceptible to attack, and even if the missile were still secure in it's coffin launcher, the coffins weren't particularly 'hardened' against nuclear attack. Still would be a cool looking effect for a MR launch.

Later Atlas's and Titan I's were put in underground silos, with elevators to raise them to the surface for fuelling and launch. Still vulnerable during the long time they were being fuelled and readied for launch. At least one Titan I was 'hot fired' successfully from the bottom of the silo, since all the liquid fuelled missiles had exhaust ducts to the surface (again, which were vulnerable to attack).

Most Russian missiles up until say 20 years ago or so were primarily liquid fuelled, storable hypergolic liquid fuels, like Titan II, so they could sit 'instantly ready' in the silos like solids, but still were more finicky and fragile than solids like Minuteman and SS-13 Savage (Russia's first solid ICBM). Even their SLBM sub missiles were liquid fuelled for a long time, but there was a significant safety and performance "push" to develop solid fuel missiles for subs. All the new Russian ICBM's (Topol M, Bulava, etc.) are solid fuelled (as are China's ICBM's and SLBM's, and India's IRBM's) Interestingly enough, Russia, China, and India are also foregoing silo basing, instead switching to land-mobile transporter/erector/launcher setups, or railroad based launchers (India, though even those are being phased out from what I've read-- India NEVER fielded a silo based missile). Silos are now considered too vulnerable.

Russian missiles were generally 'cold launched' from the silos, using a gas-generator system and a launcher 'plug' quite similar to a piston launcher or an ejection piston in MR. The missile sat on this 'plug' and when it was fired, the gas generator blew the missile up out of the silo; once clear, the plug launcher seperated from the missile, and was propelled to one side by laterally facing (solid?) rockets, as the main liquid engines on the missile itself fired up. This acted much like a piston launcher and actually extended the range or throw weight of the missile, as well as protecting the silo from the engine blast, allowing for easier reloading. Much the same systems are used aboard submarines-- the missiles are actually 'blown' out of the submarine by compressed air, and the rocket engine is ignited only after it has cleared the surface.

THAT would a cool setup! JR
 

luke strawwalker

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I can't say that I have actually ever seen videos of any of the rockets that you mentioned being launched out of their silos, nor have I ever seen anything other than a very schematic diagram of any of their silos (and that was just for the Atlas). I was just guessing about the flame tunnels. The Soviets used them for their N-1 (which of course was launched from the surface, but the flames went into a hole in the ground and then vented back up at an angle at the surface).

MarkII
Yep... they do that for SOYUZ too... and probably Proton and Energia/Buran/Vulcan as well (though I don't have pics of those).

There's plenty of vids on Youtube among others... I'll have to see if I can find some. I've also got some "Spacecraft Films" videos that show some missile launches, as well as some of the Peter Kuran atomic films that show some missile launches... "The Rainbow Bombs" has several I think, as does "Beyond Trinity, the Atomic Bomb Movie". All of those are previewed on YouTube...

Later! OL JR :)
 

Fred22

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I digress a little bit. The Peace Keeper (PK) actually has a solid propellant charge that fires into a small water reservoir to create steam (steam/gas generator). There is a lip seal on the side of the PK that makes a good enough seal that the steam ejects the missile from the silo. Once clear of the silo the PK is ignited like a submarine launched missile. An advantage of this method is that the silo can be re-loaded with another PK quickly without much refurbishment. The Russians use the same idea for their solid ICBM's.

Bob
Thats interesting thanks:)
Cheers
fred
 

luke strawwalker

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The Minuteman didn't have fins, right? (But your model will need them.) I wonder how small of a span you could get away with?

Interesting design. Question: Was a silo ever meant to fire more than one missile in its service life? (IOW, did the USAF ever think that there would be more than one volley of missiles fired during Armageddon?)











Sliding silo cover....



The air vents are visible in the foreground in this photo.





MarkII
In theory, yes, at least Russian silos were designed for re-use. SOME American silos were probably also envisioned with the capability of being reloaded, but realistically... probably not.

The Minuteman missiles were often rotated amongst a larger number of silos. They were 'secretly' hoisted out of their silos for periodic testing and maintenance, and moved to different silos. That way you kept the enemy guessing-- which silos are empty, and which are loaded?? The enemy would have to keep a greater stockpile of warheads if he wanted to hit EVERY SINGLE SILO, regardless of whether it was loaded or not. The missiles were transported in large canister trucks. The canister was erected over the silo, and a 'tent' was erected around the base of the transporter to block all view from the outside (including satellites) and then the missile was hoisted up out of the silo into the canister, or lowered from the canister into the silo. The silo door was put back in a way so the enemy satellites couldn't see if there was actually a missile in the silo or not... the canister trucks COULD set up and PRETEND to remove a missile from the silo while actually leaving it behind, OR actually remove the missile, and likewise, a truck could deliver a refurbished missile to a different silo, OR pretend to load a missile into an empty silo. No way to know for sure, so it certainly made your targeting package updates interesting!

The Minuteman silos were rather simple, like a concrete tube in the ground. The Atlas, Titan I, and Titan II silos were MUCH more sophisticated, since the missiles had to be serviced in the silo, and there was MUCH more stuff to work on (see the film "Star Trek First Contact" filmed in the Yuma AZ Titan Missile Museum silo with an actual Titan II to get my drift-- the missile is SURROUNDED by folding work platforms and equipment, all of which would be damaged to some degree or other by the missile launch from the silo. Therefore they'd be harder to reuse without significant maintenance.

The Russians used MOSTLY storable hypergolic liquid fuelled missiles, much like the Titan II. They devised the 'cold launch' method used on submarines and adapted it to their land-based ICBM's, which resulted in a slight performance increase as well as making the silo MUCH easier to reload.

Who would have been left to reload them, or been in any condition to or had anything reload them with?? That's a different matter... OL JR :)
 

Fred22

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Nope, no problems at all... maybe some "slight staining" from smoke on the plexi fins, nothing else.

I don't know how much the damp clay earth cooled the exhaust, but I doubt it was a whole lot, relatively speaking. The exhaust gases from our engines cool fairly decently just by expansion and mixing with ambient air, which the silo would be full of. By the time the exhaust flame streams out, hits the deflector (heating it up and cooling the gases), spreads out across the deflector, and starts curving back up again, it's had a LOT of mixing and time to cool, much like an ejection baffle. So long as your rocket isn't sitting 1/2 inch above the silo 'floor' and has more than 1/2 inch of clearnance all the way around (which would be necessary for the fin span I would think) it should be fine. If in doubt, give yourself a little greater 'depth' to the silo actually below the rocket, to give a greater air volume below the rocket for the exhaust to mix with, and a little more 'time/distance' for the exhaust gases to travel before they start back up around the rocket.

I only had a few grainy pictures to go by from Bill Gunston books we had in our high school library back when I built mine-- so I had to 'scale from photographs'... get one measurement you know (diameter from the text is a good one, or overall length) and then using dividers and an drafting scale, measure out every point in the picture, then plug the measurements into a 'scaling factor' derived from the ratio of the pic measurement of length or diameter to the real thing. Of course this doesn't account for perspective, so there is some error in this method, especially on shots where the rocket is not precisely 90 degrees to the camera. Small image size also reduces the "fidelity" of the data, since the greater the 'scaling ratio', the more 'unsure' the measurements are (more uncertainty) Close up photos, however, usually suffer more from perspective changes, especially on long tall objects like rockets... the camera *might* be close to perpendicular to the bottom third of the rocket, but the upper 2/3 might be at a significant angle (30-40-50 degrees or more) to the camera and that introduces SIGNIFICANT perspective errors, especially in length measurements. Diameters are less affected, but they DO develop errors due to perspective effects... (railroad tracks coming together in the distance though they are parallel).

Much MUCH easier scaling from drawings... :)

Good luck! OL JR :)

PS. That reminds me of one of the other methods that was employed by the Atlas missile-- COFFIN LAUNCHERS! These were steel and concrete structures with steel doors on top for a roof, in which the missile was stored horizontally in a cradle. To launch, the missile doors were opened, then the missile was stood upright, the cradle retracted, and the missile was fuelled and launched. VERY susceptible to attack, and even if the missile were still secure in it's coffin launcher, the coffins weren't particularly 'hardened' against nuclear attack. Still would be a cool looking effect for a MR launch.

Later Atlas's and Titan I's were put in underground silos, with elevators to raise them to the surface for fuelling and launch. Still vulnerable during the long time they were being fuelled and readied for launch. At least one Titan I was 'hot fired' successfully from the bottom of the silo, since all the liquid fuelled missiles had exhaust ducts to the surface (again, which were vulnerable to attack).

Most Russian missiles up until say 20 years ago or so were primarily liquid fuelled, storable hypergolic liquid fuels, like Titan II, so they could sit 'instantly ready' in the silos like solids, but still were more finicky and fragile than solids like Minuteman and SS-13 Savage (Russia's first solid ICBM). Even their SLBM sub missiles were liquid fuelled for a long time, but there was a significant safety and performance "push" to develop solid fuel missiles for subs. All the new Russian ICBM's (Topol M, Bulava, etc.) are solid fuelled (as are China's ICBM's and SLBM's, and India's IRBM's) Interestingly enough, Russia, China, and India are also foregoing silo basing, instead switching to land-mobile transporter/erector/launcher setups, or railroad based launchers (India, though even those are being phased out from what I've read-- India NEVER fielded a silo based missile). Silos are now considered too vulnerable.

Russian missiles were generally 'cold launched' from the silos, using a gas-generator system and a launcher 'plug' quite similar to a piston launcher or an ejection piston in MR. The missile sat on this 'plug' and when it was fired, the gas generator blew the missile up out of the silo; once clear, the plug launcher seperated from the missile, and was propelled to one side by laterally facing (solid?) rockets, as the main liquid engines on the missile itself fired up. This acted much like a piston launcher and actually extended the range or throw weight of the missile, as well as protecting the silo from the engine blast, allowing for easier reloading. Much the same systems are used aboard submarines-- the missiles are actually 'blown' out of the submarine by compressed air, and the rocket engine is ignited only after it has cleared the surface.

THAT would a cool setup! JR
I wonder if i will get a neat puff of smoke coming out with the rocket? Using any kind of pressure system would be cool but far beyond my capabilities i think. A neat coffin launcher for a future project would be a BOMARC in Canadian colours naturally :) I remeber your point about the vulnerability of silos:) They were talking once about dense pack defence. I think they would have got around that one by just using one big one:)
Cheers
fred
Cheers
fred
 
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