Ramjet artillery shell of a big size

In summary, the person is trying to come up with a 1000km range artillery shell that uses a ramjet engine. They have some parameters to work with, such as height, thickness, and material of the shell, as well as the weight of the shell without engine or fuel. The range is 1000km, the max speed the shell could fire, and the fuel and engine that the person is considering.
  • #1
Destroyer500
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I will copy paste a post i made on another forum.Its just a fun project i started and i hope people in here are going to be able to help.I am not an aerospace engineer but im studying electrical and electronic engineering so i am familiar with formulas math and physics (up to a degree of course).Ok so here it goes
I was playing with CHATgtp trying to get some answer but the thing has got me really confused.So i was wondering if i could take the Schwerer Gustav make it 1000mms instead of 800 (talking about the bore) put it on a stationary platform not a rail car and then give it a ramjet shell with the aim of achieving a 1000km range.Yes it may sound very ambitious especially for the era but this is a fun project and since im not an aerospace engineer and chat gtp wont answer properly i came here.Now ill give you some parameters to work with

The height of the shell is going to be 8 meters and the thickness of its side walls i assume 30-40mms.Thickness of the base is going to be 150-200mms.
The material i chose is titanium since i cant think of anything better for the era.
We get a mass of 4.3 tons for the shell with a 0.96 cubic meters volume,which is the shells volume.5.31 cubic meters is going to be the internal volume which is the free space were gonna have inside of it to put all the goodies.
Now that calculation wasnt made with the exact shape of the shell in mind.I just considered it to be a cylinder for ease of calculations.Keep in mind that i want this to be as aerodynamic as possible to reduce the drag coeficient and save fuel.If im going to get less space ill do it
I want a payload of 2000kg on the thing so total weight of the shell without engine or fuel is close to 6.3 tons

After messing around a lot i learned some stuff about ramjet and jet engines so ill give some extra parameters that i consider a very high priority millitary project of any very advanced nation of the 30s-40s would be able to achieve in 10 years.For example if the development of the ramjet shell started in 1930 we expect the project will have provided a working prototype ready to enter production in 1940.The technology was there a long time ago but noone cared to really develop it be that for artillery or planes.Lets assume an efficiency for the ramjet of 22.5% and an ISP of 1700.Although there are multiple variables that determine these two numbers that i provided as i said its just for a rough estimation.I mean unless youre willing to go very technical and calculate the parameters using what was achievable with a huge funding the best scientists available at the era and the best materials they could get :) If you want to do so then id be happy but please be as technical as possible.

Now i dont know what fuel i could use but kerosene is what was used typically so use that unless you have something better to propose.The range is going to be 1000km and the max speed the gun could fire the thing is going to be 900m/s.We may be able to somehow rocket assist the shell to reach 1000m/s if we want our ramjet to activate at higher speeds and the CHATgpt,which ill call my robot battler from now on,said that we wont need much extra fuel with oxidizer inside the shell to achieve that extra 100m/s so it may be viable.At least very broadly speaking.But our ramjet doesnt have to start on mach 3 no matter what.

Now you may say,how are you going to guide the thing over such a distance ? Well the latter V2 rockets had very simplistic designs regarding radio guidance,at least when they took off,so we could make "antenas" all the way from the cannon to its targets,or just line up vehicles having them and crudely radio guide it.We could even have some sort of fritz x guidance system on it,have a plane fly near the end of the things journey,have the shell throw flares or tracers or something once it reaches its max range so that the plane can see it and then have the plane guide it like the fritz x bomb.That would require small wings and maybe some sort of flaps or something to slow the shell down cause i doubt the people on the plane are going to be able to guide it at very high velocities.I propose the fritz x thing since the hardest part of controling a missiles path is on the descend and since we care for accuracy i cant think of any better way for it to be done for the era.

Now,i learned recently of something called lifting body principle and it would be cool if it could be used to move the thing at long distances with less fuel.However i also understand that its structure would have to be reinforced and its geometry altered.We also dont need to go extra high to utilize lifting body from what i learned but im not sure.

Now all the things i mentioned have to fit inside the shell and help it do its thing.My biggest concern is the space that the fuel is going to require.Im afraid it is going to be too much for just 5.3 cubic meters which is mostly going to be 3-2.5 cubic meters since the rest are going to be taken by the engine and payload,unless the engine isnt going to require much space.
Also for anyone saying its not possible then go read this https://en.wikipedia.org/wiki/Ramjet and this https://www.wearethemighty.com/mighty-trending/new-artillery-cannon-1000-miles/ and then watch this But im sure many of you already know how many applications there are for ramjets.

Edit;While i left my PC i remembered that i forgot to mention certain parameters that may help with certain calculations.Its late though so ill mention them tomorrow.I know this whole project would require a far greater amount of work and a lot of people but as i said its for fun
 
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  • #2
To solve the engineering optimisation puzzle, it needs to have a purpose.

Unlike Project HARP, a ramjet must fly low enough to breathe air.
You are proposing a hypersonic cruise missile.

A heavy gun cannot be moved. Why do you insist on launching the missile from a heavy gun barrel, rather than from a rail, or an aircraft ?

Why will you not consider inertial navigation or GPS for guidance ?
 
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  • #3
Baluncore said:
To solve the engineering optimisation puzzle, it needs to have a purpose.

Unlike Project HARP, a ramjet must fly low enough to breathe air.
You are proposing a hypersonic cruise missile.

A heavy gun cannot be moved. Why do you insist on launching the missile from a heavy gun barrel, rather than from a rail, or an aircraft ?

Why will you not consider inertial navigation or GPS for guidance ?
Hello and thanks for answering :)

Ok so the purpose of the gun is to fire the ramjet shell and achieve huge ranges while carrying a very big payload.Now one could ask why not use a missile ? Well theres 3 reasons;1)a missile requires a massive amount of fuel and oxidizer compared to a ramjet and firing large artillery shells is going to be a lot more cost efficient than launching a missile 2)the technology for such a missile wasnt available back then but even if it was i still think a ramjet would be a better option 3)due to the fact the shell is being fired from a gun it doesnt have to propel itself to reach that initial velocity required for the ramjet to fire up and thus we save on a lot of fuel.

Also its not a missile its an artillery shell.The moment it exits the barrel and reaches a safe distance the ramjet will activate and propel it for as much as its needed.If the US can achieve a 1000mile range with such a small caliber,they dont state the calliber but it certainly isnt 1000mms,then why cant it be done with something bigger using more fuel that uses the same principles ? Its also not really a hypersonic since i dont think it would be able pick up that much speed on its journey.Apart from the descent phase of course but even that wont reach 2km/s cause as i said i want the thing to lose speed during the latter parts of its journey so that the plane can somewhat guide it.

Im not considering inertial or GPS guidance because this is a 1930-40s hypothetical project.Of course if i made it using modern tech a lot of things would be a lot easier.Ramjet artillery shell had been proposed as early as 1910s but noone cared to develop them.

Now of course thats my opinion and im no expert so feel free to judge me as much as you want.I dont want you to pat me in the back in any way but expect that im going to defend my ideas as much as that makes sense.I say it now so that i dont say it latter
 
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  • #4
For what you ask, the up-front cost of the barrel would be prohibitive. The barrel would weigh and cost more than all the shells it could fire before it needed a re-bore.
The V1 was a pulse-jet missile that was launched up a ramp by a steam catapult. There was no barrel needed.
 
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  • #5
Destroyer500 said:
Hello and thanks for answering :)
1)a missile requires a massive amount of fuel and oxidizer compared to a ramjet
That already has a name/design: it's a cruise missile. A missile that uses a jet engine instead of a rocket (regardless of jet type). They already exist and seem to meet your performance requirements:
https://en.wikipedia.org/wiki/Hypersonic_weapon
https://en.wikipedia.org/wiki/Cruise_missile
and firing large artillery shells is going to be a lot more cost efficient than launching a missile
Your description merges the two: your "artillery shells" aren't normal artillery shells; they a lot more expensive. More like...cruise missiles.
2)the technology for such a missile wasnt available back then but even if it was i still think a ramjet would be a better option
V1 was mentioned, but regardless...
3)due to the fact the shell is being fired from a gun it doesnt have to propel itself to reach that initial velocity required for the ramjet to fire up and thus we save on a lot of fuel.
That's the only real difference here. The typical solution is a booster rocket. You're just replacing the booster rocket with a gun. It's debatable which would be better, but 50 years of choosing rocket boosters must have a reason. (The V1 might have been rail launched?).
Also its not a missile its an artillery shell.The moment it exits the barrel and reaches a safe distance the ramjet will activate and propel it for as much as its needed.
You're using one name and describing something that already has a different name.
 
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  • #6
Baluncore said:
For what you ask, the up-front cost of the barrel would be prohibitive. The barrel would weigh and cost more than all the shells it could fire before it needed a re-bore.
The V1 was a pulse-jet missile that was launched up a ramp by a steam catapult. There was no barrel needed.
No it wouldnt really.It would cost along with the whole instalation needed to house it,turn it,elevate it,reload and protect it as much as a small destroyer and the people it would need to man be close to those needed to man a destroyer if not less.The Gustav fired a total of 300 shots along with the ones it fired during testing.Now the guns i propose could also be made smoothbore to reduce that wear and tear since theyre not going to be firing standard shell.
russ_watters said:
That already has a name/design: it's a cruise missile. A missile that uses a jet engine instead of a rocket (regardless of jet type). They already exist and seem to meet your performance requirements:
https://en.wikipedia.org/wiki/Hypersonic_weapon

Your description merges the two: your "artillery shells" aren't normal artillery shells; they a lot more expensive. More like...cruise missiles.

V1 was mentioned, but regardless...

That's the only real difference here. The typical solution is a booster rocket. You're just replacing the booster rocket with a gun. It's debatable which would be better.

You're using one name and describing something that already has a different name.
To be honest with you i dont know how to name it :D People here and on many websites call it an artillery shell.Of course i understand that their use and purpose resembles more that of a cruise missile.
Replacing the booster rocket seems like a good idea since the thing wont be that big and it wont require that much fuel.However thats an oxymoron since the gun will be far bigger than any kind of missile.I will rethink the rail launched missile using a ramjet a little bit more but i think there was a reason i chose the gun instead of the rail system
Again both of you thanks for answering
 
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  • #7
Destroyer500 said:
To be honest with you i dont know how to name it :D People here [vid] and on many websites call it an artillery shell. Of course i understand that their use and purpose resembles more that of a cruise missile.
And critically, that video says 150 km range. You specified 1,000 km, which matches typical cruise missile performance*. You need 6x the fuel, so the end product has to be much larger than what they are showing, which they pointed out has the same dimensions as a normal shell.

I see a benefit to an extended range but otherwise normal artillery shell, but your performance requirements appear to break some of those benefits while making them more similar to cruise missiles in capabilities.

*from wiki: "The United States, Russia, North Korea, India, Iran, South Korea, Israel, France, China and Pakistan have developed several long-range subsonic cruise missiles. These missiles have a range of over 1,000 kilometres." Supersonic cruise missiles tend to have shorter ranges.
 
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  • #8
russ_watters said:
And critically, that video says 150 km range. You specified 1,000 km, which matches typical cruise missile performance*. You need 6x the fuel, so the end product has to be much larger than what they are showing, which they pointed out has the same dimensions as a normal shell.

I see a benefit to an extended range but otherwise normal artillery shell, but your performance requirements appear to break some of those benefits while making them more similar to cruise missiles in capabilities.

*from wiki: "The United States, Russia, North Korea, India, Iran, South Korea, Israel, France, China and Pakistan have developed several long-range subsonic cruise missiles. These missiles have a range of over 1,000 kilometres." Supersonic cruise missiles tend to have shorter ranges.
I also send a link about the US making a gun that has a ramjet shell that reaches 1000miles.But i found more
https://i.pinimg.com/originals/25/a9/29/25a929867e5176b0aff941ed2a5e69b0.jpg
https://www.nextbigfuture.com/2020/...s-could-create-global-trench-warfare-2-0.html
https://www.globalsecurity.org/military/systems/ground/slrc.htm
https://topwar.ru/175469-sverhbolshaja-dalnost-i-optimizm-proekt-strategic-long-range-cannon.html
 
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  • #9
Destroyer500 said:
Thanks, interesting stuff. One quote sticks out to me though:
"The limited literature on this gun is long on heavy breathing and short on details."
 
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  • #10
A 'fixed' gun barrel requires a lot of materiel up-front, represents a 'Big Juicy Target'.

IIRC, German V3 system, which used multiple charges in barrels' 'side-pockets' proved an abysmal failure. Worse, battery could neither dodge nor hide when RAF came knocking. Aren't the massive remnants still deep under their hill, albeit as 'war grave'??
Didn't Gerald Bull begin building that 'Supergun' for Iraq, which could either be the 'benign' zero-stage of a cube-satellite launcher or a 'seriously un-neighbourly' sub-orbital bombardment system ? Too big to hide, and one of the potential targets sent assassins...

IMHO, a super-gun is a very inefficient way to reach ram-jet break-even speed. IIRC, the slew of 50s & 60s ramjet Surface-to-Air missiles (SAMs) had solid first-stage booster rockets, allowing 'zero-length' launch. Then the 'sustainer' lit...

At a pinch, you could 'split the difference' using something like the M551 "Sheridan" AR/AAV. Also, see...
https://en.wikipedia.org/wiki/List_of_gun-launched_missiles
 
  • #11
Destroyer500 said:
firing large artillery shells is going to be a lot more cost efficient than launching a missile
No, it depends entirely on the cost of the shell and gun vs the cost of the missile and launching apparatus. Cost mainly scales with two things. Size and complexity. A 5-6 ton 'artillery shell' with a ramjet engine is going to cost something comparable to a cruise missile of similar size. How much the gun would cost, I can't say.

Destroyer500 said:
.If the US can achieve a 1000mile range with such a small caliber,they dont state the calliber but it certainly isnt 1000mms,then why cant it be done with something bigger using more fuel that uses the same principles ?
What has a 1000 mile range? The 155mm artillery shell in the video had a 150 km range I believe. Did I miss something?
Destroyer500 said:
Its also not really a hypersonic since i dont think it would be able pick up that much speed on its journey
Then why use a ramjet? Ramjets are very inefficient at non-hypersonic speeds.
 
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  • #12
A few (minor?) things to consider:

During/after WWII the U.S. Navy Pacific Fleet was based In Long Beach, Calif. Since much ship construction and repairs were expected, there was a steel plant located about 45 miles inland (Kaiser Steel mill in Fontana, CA.) That was just over the artillery range of a Japanese battleship. In the same general area was the only manufacturing plant on the West coast that had the large machinery needed to bore and rebore the large artillery on our ships. (Parent company was Benchmaster which manufactured punch presses; sold off several decades ago.)

In light of the above, please consider the manufacturing and refurbishing needs of your gun barrel; and how you will transport it.

Also, I'm curious; what reasonable target is within the 1000 mile range of a U.S. based artillery piece?

Cheers,
Tom

p.s. It does sound like an educational, and time-consuming, hobby though!
 
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  • #13
Destroyer500 said:
The height of the shell is going to be 8 meters and the thickness of its side walls i assume 30-40mms.
The controversy of artillery shells built with any kind of 'accelerator' instead of just a 'range extender' is that you need mass to survive the initial acceleration, but in the same time to further accelerate that mass is just a nightmare.

Destroyer500 said:
consider a very high priority millitary project of any very advanced nation of the 30s-40s would be able to achieve in 10 years.
They already had planes and missiles as carriers of any kind of engines. I doubt that anybody, ever dreamed about a plane (-like thing) launched from a cannon that time. They had just enough trouble to push those thin-skinned, fragile airframes to fly.
 
  • #14
Rive said:
They already had planes and missiles as carriers of any kind of engines. I doubt that anybody, ever dreamed about a plane (-like thing) launched from a cannon that time. They had just enough trouble to push those thin-skinned, fragile airframes to fly.
I thought the same thing until today. I give you Albert Fono, a Hungarian engineer who envisioned merging an artillery shell with a ramjet engine all the way back in 1915!

"The outstanding Hungarian engineer Albert Fono was one of the pioneers of jet propulsion. His first invention of this kind the "sertial torpedo" dates back to the World War I, to the year 1915. He wanted to get a solution for increasing the range opf filed-artillery guns. According to the inventor's conception the gun-launched projectile could be united wit a ramjet propulsion unit by which the body gained acceleration. By this means it was possible to attain a long range even at low initial velocities, and heavy shells could be fired from guns of small weight. Fono submitted his invention to the Austro-Hungarian Army H.Q. but the proposal was rejected. Long after the war Fono took up the problem of jet propulsion again. He elaborated in 1928 the "air-jet engine" which was suitable for high-altitude supersonic aircraft and applied for a German patent. In an additional patent application the propulsion unit was adapted for subsonic speeds too. The patent were granted in 1932 with the priority date of May 1928 as these are the earliest which cover all the essentials of present aircraft and missile air-breathing jet engines."
ref: https://web.archive.org/web/20160303232806/http://iaaweb.org/iaa/Studies/history.pdf
Page 136 of the PDF.
 
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  • #15
Drakkith said:
No, it depends entirely on the cost of the shell and gun vs the cost of the missile and launching apparatus. Cost mainly scales with two things. Size and complexity. A 5-6 ton 'artillery shell' with a ramjet engine is going to cost something comparable to a cruise missile of similar size. How much the gun would cost, I can't say.What has a 1000 mile range? The 155mm artillery shell in the video had a 150 km range I believe. Did I miss something?

Then why use a ramjet? Ramjets are very inefficient at non-hypersonic speeds.
I dont know if it would cost that much but a single shell should cost less than a WW2 missile like the V2 which is what im aiming at.
The US talked about a 1000mile range which is 1800km in 2019
https://i.pinimg.com/originals/25/a9/29/25a929867e5176b0aff941ed2a5e69b0.jpg
https://www.nextbigfuture.com/2020/...s-could-create-global-trench-warfare-2-0.html
https://www.globalsecurity.org/military/systems/ground/slrc.htm
https://topwar.ru/175469-sverhbolshaja-dalnost-i-optimizm-proekt-strategic-long-range-cannon.html
But i dont think that my "project" could achieve such huge ranges with so ineficient engines,talking about some theoretical advanced ramjet of the 1940s,thats why i propose 1000km.
The gun cannot launch the shell faster than 900m/s with WW2 tech in mind and in such a caliber i dont think that even in modern times we could have it go faster.Unless we filled the guns barrel with electromagnets or something and apart from the propellant the shell was accelerated via them (talking about modern times) but even then i doubt it can go faster than 1300m/s.I havent calculated it but its a rough guess.Now ramjets can fire up at lower speeds and of course the thing will accelerate to a higher speed,especially in its descend but how much can that be with 1940s tech ? I dont think they had advanced ceramics back then :D On the other hand the V2 on its descend reached very high speeds so maybe its doable ?
 
  • #16
Tom.G said:
A few (minor?) things to consider:

During/after WWII the U.S. Navy Pacific Fleet was based In Long Beach, Calif. Since much ship construction and repairs were expected, there was a steel plant located about 45 miles inland (Kaiser Steel mill in Fontana, CA.) That was just over the artillery range of a Japanese battleship. In the same general area was the only manufacturing plant on the West coast that had the large machinery needed to bore and rebore the large artillery on our ships. (Parent company was Benchmaster which manufactured punch presses; sold off several decades ago.)

In light of the above, please consider the manufacturing and refurbishing needs of your gun barrel; and how you will transport it.

Also, I'm curious; what reasonable target is within the 1000 mile range of a U.S. based artillery piece?

Cheers,
Tom

p.s. It does sound like an educational, and time-consuming, hobby though!
The gun barrel will be transported via ship,rail or some specialized truck-trucks.I do understand that this wont be easy at all but o well :) Manufacturing will require a completely new set of tools and machinery unless naval gun manufacturing plants can somehow be repurposed but i doubt it
The thing with the US is that it doesnt have any suitable target so it will have to transport it to allied nations like Britain,France or something that can use them against a variety of targets if the need arises.In general the US will only manufacture and transport them not use them.
Initially i though with a few guns on Anchorage maybe Japan could be hit but then i saw how big of a distance that is and i reconsidered.
I consider it a fun hobby and the feasibility of this idea will decide weather or not i will make a scale model out of it :)
 
  • #17
Rive said:
The controversy of artillery shells built with any kind of 'accelerator' instead of just a 'range extender' is that you need mass to survive the initial acceleration, but in the same time to further accelerate that mass is just a nightmare.They already had planes and missiles as carriers of any kind of engines. I doubt that anybody, ever dreamed about a plane (-like thing) launched from a cannon that time. They had just enough trouble to push those thin-skinned, fragile airframes to fly.
That mass doesnt really have to be accelerated that much in my opinion.Since the shell will follow a ballistic arc the hardest part will be the ascending one.Also as i said at point it would be nice if the shell geometry could be altered to utilize at "low" altitude the lifting body principle.That would save even more fuel and maybe extend the range.

Drakkith said:
I thought the same thing until today. I give you Albert Fono, a Hungarian engineer who envisioned merging an artillery shell with a ramjet engine all the way back in 1915!

"The outstanding Hungarian engineer Albert Fono was one of the pioneers of jet propulsion. His first invention of this kind the "sertial torpedo" dates back to the World War I, to the year 1915. He wanted to get a solution for increasing the range opf filed-artillery guns. According to the inventor's conception the gun-launched projectile could be united wit a ramjet propulsion unit by which the body gained acceleration. By this means it was possible to attain a long range even at low initial velocities, and heavy shells could be fired from guns of small weight. Fono submitted his invention to the Austro-Hungarian Army H.Q. but the proposal was rejected. Long after the war Fono took up the problem of jet propulsion again. He elaborated in 1928 the "air-jet engine" which was suitable for high-altitude supersonic aircraft and applied for a German patent. In an additional patent application the propulsion unit was adapted for subsonic speeds too. The patent were granted in 1932 with the priority date of May 1928 as these are the earliest which cover all the essentials of present aircraft and missile air-breathing jet engines."
ref: https://web.archive.org/web/20160303232806/http://iaaweb.org/iaa/Studies/history.pdf
Page 136 of the PDF.
If it wasnt for this guy i wouldnt even say what im saying at this thread
 
  • #18
Destroyer500 said:
That mass doesnt really have to be accelerated that much in my opinion.
If you give up on the unrealistic ramjet and go with 'simple' RAP or Base Bleed , then it's barely doable within the limits of the era, though still clearly in the 'wunderwaffe' calibre.

Drakkith said:
I thought the same thing until today.
Nice ideas, yes: indeed. I did not know about that.
Nice drawings too.

But on the engineering side he was way too early to even consider them in depth.
The proper foundations for supersonic stuff was laid in the late 40's: before and without that it was barely an idea.
 
  • #19
Rive said:
If you give up on the unrealistic ramjet and go with 'simple' RAP or Base Bleed , then it's barely doable within the limits of the era, though still clearly in the 'wunderwaffe' calibre.Nice ideas, yes: indeed. I did not know about that.
Nice drawings too.

But on the engineering side he was way too early to even consider them in depth.
The proper foundations for supersonic stuff was laid in the late 40's: before and without that it was barely an idea.
It was barely an idea because they didnt care for it nor did they have the money they needed http://enginehistory.org/Rockets/LorinRamjet/LorinRamjet.shtml
If there were more people and a lot more funding thrown into research then ramjets would be a thing earlier.
The concept was theorized 25 years before the 30s and if in the interwar period more development was done on them then who knows how good would they be by the 30s.Hell 25 years before the 30s they were playing with the idea of using them on artillery shells so what if they cared to integrate the idea in the interwar period instead of the postwar one ? Technology of this kind advances only once people are interested to pour energy and time on it.If Verner von Braun wasnt asked to make a rocket in the 40s that could be weaponized the tech wouldnt be there up until the early-mid 50s.Which means that rockets wouldnt be understood as well up until the mid to late 60s.And we may not have been to space or the moon or anything up until the late 70s.
Of course thats purely a hypothesis but again and its a hypothesis where everything else in the "timeline" remains the same but again as i said if enough energy and time is poured into something it can be done far faster that if its left to be developed and discovered naturally.
Now i didnt come to this forum to discuss about the feasibility of it but to prove it or disprove it with actual formulas and what not.I also came here because the formulas that CHAT GTP provided were changing every time i asked it.If anyone would be willing to help me calculate the ISP,efficiency,thrust per kg,fuel consumption,mass and volume of a hypothetical ramjet i would be greatfull.I have already found a lot of formulas on the internet but dont know how to use them and since the drawing board stage is all well ever get for such a project like mine formulas are all that matters.
For example i found these https://www.aoe.vt.edu/people/faculty/lowe/air-breathing-propulsion-calculator.html https://physicscalc.com/physics/drag-equation-calculator/
https://www.grc.nasa.gov/WWW/k-12/airplane/ramth.html But i have to already know certain of the values im going to use which i dont.Apart from that i dont really know how certain of these values can be found while others i dont even recognize.Its not my job after all :)
Edit;Could the lifting body principle be used on the said shell along with ramjet on the low altitudes were gonna be using it ?
Also base bleed and RAP as was mentioned can not extend the range as far i would like so theyre mostly out of the question without the ramjet incorporated
 
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  • #20
Destroyer500 said:
Now i didnt come to this forum to discuss about the feasibility of it but to prove it or disprove it with actual formulas and what not.
Using the equations for a ballistic projectile, and simplifying things to assume no air resistance and a flat surface, a projectile with a range of 1,000 km would require an initial velocity of around 3300 m/s and would achieve a height of over 400 km above the Earth. It would take about 475 seconds from launch to impact.

Let's say that the 1st quarter of that time is within the atmosphere (ballpark guess). We have roughly 2 minutes from launch until our ramjet no longer works because we are outside of the atmosphere. Assuming a launch velocity of about 800 m/s, the ramjet would have to make up about 2500 m/s in 120 seconds. That's an average acceleration of about 21 m/s2, or just over 2 g's. But we didn't actually launch at 3300 m/s, so we can add another minute or two to our time and perhaps reduce our acceleration requirement a smidge.

That's all a very, very rough calculation but I hope it gives you some idea of what you're asking. Is it doable with 1940's tech? With great effort and expense, probably. Is there any reason to do this? No, not at all. It's an absolute waste of resources. You just have a more expensive version of the V1 cruise missile that's even less accurate.
 
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  • #21
Drakkith said:
Using the equations for a ballistic projectile, and simplifying things to assume no air resistance and a flat surface, a projectile with a range of 1,000 km would require an initial velocity of around 3300 m/s and would achieve a height of over 400 km above the Earth. It would take about 475 seconds from launch to impact.

Let's say that the 1st quarter of that time is within the atmosphere (ballpark guess). We have roughly 2 minutes from launch until our ramjet no longer works because we are outside of the atmosphere. Assuming a launch velocity of about 800 m/s, the ramjet would have to make up about 2500 m/s in 120 seconds. That's an average acceleration of about 21 m/s2, or just over 2 g's. But we didn't actually launch at 3300 m/s, so we can add another minute or two to our time and perhaps reduce our acceleration requirement a smidge.

That's all a very, very rough calculation but I hope it gives you some idea of what you're asking. Is it doable with 1940's tech? With great effort and expense, probably. Is there any reason to do this? No, not at all. It's an absolute waste of resources. You just have a more expensive version of the V1 cruise missile that's even less accurate.
Then the alternative is a lifting body with ramjets design.But we dont need to go super high for that nor super fast.Yes i know lifting body designs are for reentry vehicles but i read that they work for lower speeds as well.Lifting body principle in my mind seems to work like a flying paper plane.
I consider such firepower worth the hustle.Accuracy will not be such an issue cause there are ways to fix it but thats not what i want to talk about currently
 
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  • #22
It strikes me that you are not listening to what you are being told. Presumably, you asked your question on this forum because you recognize that at least some of the folks here know what they are talking about. Why do that and then not listen? You seem to be trying to force a particular solution to a problem that doesn't exist.
 
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  • #23
Destroyer500 said:
Now i didnt come to this forum to discuss about the feasibility of it
Apparently, you are after some kind of stempunk-like feeling: modern, cutting edge design projected back in time and done with unsuitable level of technology, regardless the realities.

x2MgsY81vKV_i2jKGbqCIjy1_2Xkjqd8GOAhklB5a9c.jpg


I think this still can be discussed, but should be a nominate for the Sci-fi parts of the forum instead.
 
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  • #24
Destroyer500 said:
Then the alternative is a lifting body with ramjets design.But we dont need to go super high for that nor super fast.
Yes, you do. It doesn't matter what tweaks you make to your design. If you want a 1,000 km range without strapping wings on it and making it a long range cruise missile then you MUST launch it on a ballistic trajectory into space. It either flies the entire way like an aircraft, or you are launching it into space. And if you're launching it into space, then it's going to follow a trajectory close to what I gave.
Destroyer500 said:
I consider such firepower worth the hustle.Accuracy will not be such an issue cause there are ways to fix it but thats not what i want to talk about currently
I can't fathom how you could drastically improve accuracy with 1940's era technology. Germany could barely hit London at a range of 200-300 km with V1's and V2's. Increasing the range 3x-5x more is only going to make things more difficult.
 
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  • #25
Drakkith said:
Yes, you do. It doesn't matter what tweaks you make to your design. If you want a 1,000 km range without strapping wings on it and making it a long range cruise missile then you MUST launch it on a ballistic trajectory into space. It either flies the entire way like an aircraft, or you are launching it into space. And if you're launching it into space, then it's going to follow a trajectory close to what I gave.

I can't fathom how you could drastically improve accuracy with 1940's era technology. Germany could barely hit London at a range of 200-300 km with V1's and V2's. Increasing the range 3x-5x more is only going to make things more difficult.
I never said im not going to strap some wings on the thing :) Even modern ramjet artillery shells have small wings.I was baffled at first at the extreme height the shell would reach and i knew i had forgotten to say something.Basically what i aim to do with this "project" is eliminate the fuel required by a rocket booster to get the shell to an adequate enough speed for the ramjet to fire up.If i wanted to rocket boost the payload throughout its entire journey i would need a very big booster,a lot of fuel and at that point its basically a ballistic which is too costly per unit.Basically i imagine my shell as being a mixture between an artillery shell,a cruise missile and a glide bomb.The cost will be high for the guns and the whole emplacement though so its not a total win win.Im using the same arguments the people that were going to built the US SLRC used by the way :) Other than that i can only think of a rail launched missile that will be rocket boosted up until the speed the ramjet requires and then it will fly pretty much like the shell.I dont know though how much fuel will something of this kind require for the boosting and how expensive per unit will it end being due to that.The V2 was 12 tons and 10 of those were the fuel and oxidizer.
From wikipedia we read
Some later V-2s used "guide beams", radio signals transmitted from the ground, to keep the missile on course, but the first models used a simple analog computer
Dr. Friedrich Kirchstein of Siemens of Berlin developed the V-2 radio control for motor-cut-off (German: Brennschluss).[16]: 28, 124  For velocity measurement, Professor Wolman of Dresden created an alternative of his Doppler[39]: 18  tracking system in 1940–41, which used a ground signal transponded by the A-4 to measure the velocity of the missile.[3]: 103  By 9 February 1942, Peenemünde engineer Gerd deBeek had documented the radio interference area of a V-2 as 10,000 metres (33,000 feet) around the "Firing Point",[40] and the first successful A-4 flight on 3 October 1942, used radio control for Brennschluss.[15]
https://en.m.wikipedia.org/wiki/V-2_rocket Its on the technical section
I am certain that countries like the US that were far better in electronics than the Germans could make something even more reliable when it comes to the guidance.
Im gonna do the same for the shell but i will place antenas on trucks throughout the whole path of the thing so that any huge deviation can be corrected.The targets are still going to be cities or factories so we dont need to be extremely accurate but we need to at least have a handful kilometers margin of error not tens of kilometers margin of error.
Im happy that i get a little bit attention on this even though it may sound as a silly idea so thanks again to everyone that has answered my questions or expressed a criticism of any sorts thus far
 
  • #26
Destroyer500 said:
i will place antenas on trucks throughout the whole path of the thing so that any huge deviation can be corrected
This is possibly the very worse part of your not very good idea.
 
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  • #27
Destroyer500 said:
Basically i imagine my shell as being a mixture between an artillery shell,a cruise missile and a glide bomb.
The altitude and time in atmosphere figures @Drakkith calculated are telling. It means you cant just split the difference and make it half ballistic and half ramjet, it has to be almost all one or the other. Either it exits the atmosphere altogether as a ballistic artillery shell or it's an all atmospheric cruise missile boosted by a gun instead of a rocket.

Obviously the accuracy can be good if you add a guidance package....

Making an artillery shell a replacement for a cruise missile to save a bunch of money sounds good, but you can't make it cheap just by calling it an artillery shell. What makes artillery shells cheap is that they are simple. When you strap on a bunch of cruise missile features it will be as expensive as a cruise missile regardless of what name you give it. Ultimately here the main thing you end up saving is the booster.
 
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  • #28
Tomahawk:
3. Subsonic is a feature, not a bug. With all the emphasis on supersonic and hypersonic missiles and with the improvements in air defenses, that might make Tomahawk seem like a fuddy-duddy by comparison.

But there are good reasons to keep producing the Tomahawk, even with its slower speeds.

“The benefit of the sub-sonic missile is range,” Clark said. “Being sub-sonic means its also able to travel at a more fuel-efficient speed. So, the fact that the Tomahawk can travel more than 1,000 miles is a function of the sub-sonic speed. To get that kind of range out of a super-sonic missile you’d need something much larger.”
https://www.defensenews.com/naval/2...aded-tomahawk-heres-5-things-you-should-know/
 
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  • #29
russ_watters said:
Ultimately here the main thing you end up saving is the booster.
Well... Not exactly. That 'artillery boosted cruise missile' will start up with some really wild acceleration, and withstanding that requires quite the design and materials.

It's not just laziness that the road of artillery shells from the simple time delay fuse to proper electronic guidance took that long.
 
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  • #30
phinds said:
This is possibly the very worse part of your not very good idea.
Theres no better way i can think off to guide the thing.which mostly means to correct its path in this case,at that time
russ_watters said:
The altitude and time in atmosphere figures @Drakkith calculated are telling. It means you cant just split the difference and make it half ballistic and half ramjet, it has to be almost all one or the other. Either it exits the atmosphere altogether as a ballistic artillery shell or it's an all atmospheric cruise missile boosted by a gun instead of a rocket.

Obviously the accuracy can be good if you add a guidance package....

Making an artillery shell a replacement for a cruise missile to save a bunch of money sounds good, but you can't make it cheap just by calling it an artillery shell. What makes artillery shells cheap is that they are simple. When you strap on a bunch of cruise missile features it will be as expensive as a cruise missile regardless of what name you give it. Ultimately here the main thing you end up saving is the booster.
Its impossible to have it exit the atmosphere and then come back,achieve such ranges and call it a conventional cannon.The only logical option is for it to be a mix between a ballistic shell,atmospheric cruise missile and a ramjet.Without the ramjet there is really no way one can achieve a balance between payload and fuel and in no way one can propel the thing at huge ranges with a standard booster.The US SLRC cannon would use a ramjet and would also launch the thing at great heights to achieve its 1000mile range but im not talking about 1000 miles here.
russ_watters said:
Nice find
Rive said:
Well... Not exactly. That 'artillery boosted cruise missile' will start up with some really wild acceleration, and withstanding that requires quite the design and materials.

It's not just laziness that the road of artillery shells from the simple time delay fuse to proper electronic guidance took that long.
Electronics will survive no problem https://en.wikipedia.org/wiki/Proximity_fuze If the Americans can put a proximity fuse on an 155mm shell then they can surely make electronics that will survive inside a 1000mm shell.Now as i said its wont really be proper guidance more like correction just like on the V2.

I have been on multiple forums and discussed a lot of ideas of mine.I will defend them as much as that makes sense so keep critisizing and thinking of ways to show me it cant be done and i will do the opposite for as long as possible.All of this of course changes if and when you show me an argument that really makes my idea redundant or at least highly unlikely the way i think of it or if i myself at some point find evidence against it.Think of it as some sort of duel ... but with words
 
  • #31
phinds said:
It strikes me that you are not listening to what you are being told. Presumably, you asked your question on this forum because you recognize that at least some of the folks here know what they are talking about. Why do that and then not listen? You seem to be trying to force a particular solution to a problem that doesn't exist.
There hasnt been a single forum where i have proposed a single thing and people agreed no matter what the topic was.So disagreement is something im used to and i dont consider it as evidence for anything.Even on gaming forums where i used to hang out when that was a hobby of mine where there isnt anything really of importance being discussed people disagree on some of the most basic things,when in certain cases it works against them and everyone has an opinion of their own.Millitary forums are even worse since there the only thing one can do without a lot of disagreement and frustration or frowned faces behind the screen is asking for pictures or some sort of document or book.And the thing with military forums is that you cant propose a thing because they take it like an insult if it goes against their opinion.Just go on any one of them and do a post about something an army doing a different attack or anything and all the grumpy grandpas wake up because you arent supposed to say that because something.
I dont work that way and i will not work that way.If something seems like it could be done then i will do everything i can to prove it and if i cant ill disprove it.
On the military forums my threads werent less than 20 pages long which is usually how much it took for someone to seriously consider what i was saying and either tell me that it couldnt be done with actual evidence or just tell me it could be done but in a different way.
Now you are smarter than them and because im bored of going in circles if you really want to disprove me it will happen if;1)you show me that the guidance system of something like the V2 wont fit inside the shell or even if it fits that it wont communicate properly with the outside world 2)you show me that with a 10 year development time and a lot of resources a highly efficient ramjet for the time or a way to propel the shell at such a distance is not achievable 3)show me that the fuel needed inside the shell will be too much and thus there isnt enough space to even propel the thing for that long.
If one of the above problems cannot be solved in any way then i will accept it and move on.If im not given an example,like it was done above where a purely balistic shells parameters were calculated,or some sort of example from tech of the era that research was being done upon but due to limitations of the time they couldnt get it to be any better and the problem wasnt that they didnt care to research the thing,then i will accept defeat and go home.Its not just out of stubornness its also about learning something.If im just being told it cant be done im really learning nothing.I want to know why it cant be done,if that is the case.
 
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  • #32
Destroyer500 said:
I am certain that countries like the US that were far better in electronics than the Germans could make something even more reliable when it comes to the guidance.
We weren't THAT much more advanced than Germany. The limiting factor in using radio beams is probably that the accuracy depends on the size of the receiving antennas (larger is better), the wavelength of the signal (smaller is better), and the separation between the transmitting towers (larger is better, within reason). The size of the antenna is set by the size of the projectile while the wavelength of the signal depends on the equipment you have available and how well the different wavelengths travel through the atmosphere and over the horizon.

Note that there were several navigation methods using radio waves as guidance signals. Even aircraft carriers commonly used them to help get their aircraft back to the ship after a mission. But none were so accurate that you could use them to guide a pilot-less aircraft to a target smaller than the size of a city.
Destroyer500 said:
Im gonna do the same for the shell but i will place antenas on trucks throughout the whole path of the thing so that any huge deviation can be corrected.
Where is this supposed to be launched from?
Destroyer500 said:
The targets are still going to be cities or factories so we dont need to be extremely accurate but we need to at least have a handful kilometers margin of error not tens of kilometers margin of error.
Factories require a margin of error in the scale of tens of meters, not kilometers.
Destroyer500 said:
I have been on multiple forums and discussed a lot of ideas of mine.I will defend them as much as that makes sense so keep critisizing and thinking of ways to show me it cant be done and i will do the opposite for as long as possible.
It is easy to defend an idea that is vague or that ignores all realistic constraints.
Destroyer500 said:
Now you are smarter than them and because im bored of going in circles if you really want to disprove me it will happen if;1)you show me that the guidance system of something like the V2 wont fit inside the shell or even if it fits that it wont communicate properly with the outside world 2)you show me that with a 10 year development time and a lot of resources a highly efficient ramjet for the time or a way to propel the shell at such a distance is not achievable 3)show me that the fuel needed inside the shell will be too much and thus there isnt enough space to even propel the thing for that long.
No one can do this because we don't have any actual specifications on anything except the size of the projectile. How big is the engine? How much thrust can it provide? How much fuel does it use at various speeds and altitudes? What altitude will your 'projectile' primarily travel at? How much drag will it have? How much fuel can it carry? How large and heavy is the guidance system, hydraulics, compressed air tanks, batteries, and/or whatever else you need to control the projectile?

I realize that you don't know any of this information, but neither do we. What would you like us to do?
 
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  • #33
Drakkith said:
We weren't THAT much more advanced than Germany. The limiting factor in using radio beams is probably that the accuracy depends on the size of the receiving antennas (larger is better), the wavelength of the signal (smaller is better), and the separation between the transmitting towers (larger is better, within reason). The size of the antenna is set by the size of the projectile while the wavelength of the signal depends on the equipment you have available and how well the different wavelengths travel through the atmosphere and over the horizon.

Note that there were several navigation methods using radio waves as guidance signals. Even aircraft carriers commonly used them to help get their aircraft back to the ship after a mission. But none were so accurate that you could use them to guide a pilot-less aircraft to a target smaller than the size of a city.

Where is this supposed to be launched from?

Factories require a margin of error in the scale of tens of meters, not kilometers.

It is easy to defend an idea that is vague or that ignores all realistic constraints.

No one can do this because we don't have any actual specifications on anything except the size of the projectile. How big is the engine? How much thrust can it provide? How much fuel does it use at various speeds and altitudes? What altitude will your 'projectile' primarily travel at? How much drag will it have? How much fuel can it carry? How large and heavy is the guidance system, hydraulics, compressed air tanks, batteries, and/or whatever else you need to control the projectile?

I realize that you don't know any of this information, but neither do we. What would you like us to do?
I have no comment on the radio guidance other than to post something i found http://www.v2rocket.com/start/deployment/leitstrahl.html
hjfghj.PNG

So it worked as i somewhat imagined

The shell is going to be launched from the gun that wont change.

On the website above it sais at some point "To hit a target within a 250 meters radius and 250 km's away" so i guess they went with 1 meter deviation for every kilometer ? So i guess in 1000km 1km deviation ? Of course its not a rocket so it work exactly like that but im just making a guess.Maybe if the plane guidance Fritz X style can reduce that deviation before the descent.

I had already written the specifications for such a shell and also some information about the engine and was about to hit send when i found out about a guy called Wolf Trommsdorff and he had exactly the same ideas as me,excluding the guidance and the giant guns
https://en.topwar.ru/165108-aktivno-reaktivnye-snarjady-v-trommsdorffa-germanija.html
https://www.fliegerrevuex.aero/mach-35-interkontinentalflugkoerper-der-luftwaffe-1944/
https://www.secretprojects.co.uk/threads/trommsdorff-projects-ww2.6832/
https://en.topwar.ru/163751-aktivno...teljami-konstrukcii-a-lippisha-germanija.html
https://min.news/en/military/f804cb68e1665e6312dc0b10a2830cb3.html

If you open this website and then book he is mentioned in the early days section https://dl.begellhouse.com/fr/download/article/0ef8891227c0632e/IJEMCP2105(1)-38741.pdf
 
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  • #34
Nik_2213 said:
IRC, German V3 system, which used multiple charges in barrels' 'side-pockets' proved an abysmal failure. Worse, battery could neither dodge nor hide when RAF came knocking. Aren't the massive remnants still deep under their hill, albeit as 'war grave'??
I knew it as "Hochdruckpumpe" - it was rendered inactive by repeated allied bombings.
https://en.wikipedia.org/wiki/V-3_cannon

Gerald Bull made a supergun from 2 16-inch (40.64 cm) naval rifles. It was not mobile but static land based.
https://en.wikipedia.org/wiki/Project_HARP

Nik_2213 said:
IIRC, the slew of 50s & 60s ramjet Surface-to-Air missiles (SAMs) had solid first-stage booster rockets, allowing 'zero-length' launch.
BOMARC used 2 ramjets with a rocket motor for launch (climb phase).
https://en.wikipedia.org/wiki/CIM-10_Bomarc

Snark was another long range cruise missile
https://en.wikipedia.org/wiki/SM-62_Snark1 km/s would be Mach 2.9, so not quite hypersonic but definitely supersonic, and with such a speed, the vehicle would have to fly at relative high altitude to have sufficient range and avoid aerodynamic heating and hydrodynamic forces. One might look at the performance of the SR-71, from what is available in the open literature.

An initial lauch could use a electro-magnetic launch system. I visited a facility that launch small projectiles at up to 3 km/s.
 
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  • #35
Astronuc said:
I knew it as "Hochdruckpumpe" - it was rendered inactive by repeated allied bombings.
https://en.wikipedia.org/wiki/V-3_cannon

Gerald Bull made a supergun from 2 16-inch (40.64 cm) naval rifles. It was not mobile but static land based.
https://en.wikipedia.org/wiki/Project_HARPBOMARC used 2 ramjets with a rocket motor for launch (climb phase).
https://en.wikipedia.org/wiki/CIM-10_Bomarc

Snark was another long range cruise missile
https://en.wikipedia.org/wiki/SM-62_Snark1 km/s would be Mach 2.9, so not quite hypersonic but definitely supersonic, and with such a speed, the vehicle would have to fly at relative high altitude to have sufficient range and avoid aerodynamic heating and hydrodynamic forces. One might look at the performance of the SR-71, from what is available in the open literature.

An initial lauch could use a electro-magnetic launch system. I visited a facility that launch small projectiles at up to 3 km/s.
I know of the V3,Bull and yesteday found out about BOMARC.Snark ive never heard off

Havent done much research on the SR-71 but i remember that it was using a scramjet so thats a bit too far fetched for the ww2 era

Electro magnetic launch ? So the projectile is fired by a standard gun and is then accelerated ? But isnt that a railgun ? Also dont railgun throw just tungsten rods so no actual explosive payload or am i wrong ?
 
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