For Questions That Don't Merit Their Own Thread

[ARS]

Why in land warfare (especially for tanks), a cannon with a caliber 120-150 mm is considered as main gun while in naval warfare a cannon with a caliber 120-150 mm (especially for battleships) considered merely as secondary weapon, with cannons of 300-400 mm caliber taking their place as heavy main gun?

Edited January 11, 2019 by ARS

[p1t1o]

1 hour ago, ARS said:

Why in land warfare (especially for tanks), a cannon with a caliber 120-150 mm is considered as main gun while in naval warfare a cannon with a caliber 120-150 mm (especially for battleships) considered merely as secondary weapon, with cannons of 300-400 mm caliber taking their place as heavy main gun?

Engagement range, nature of likely targets and size/mass of carrier vehicle vs. size/mass of weapon+ammunition.

A 300mm tank cannon round would be practically unstoppable, but your tank would weigh 500tons and have a max land speed of 3mph and a vehicle range of 30miles (wild guesses obviously, but you get it). It would also be impossible to camouflage and a sitting duck from the air.

Battleships are now obsolete, along with their armaments, main guns are now missiles and naval guns top out around the 155mm mark these days, give or take, for land targets and smaller, closer targets not worth a $500,000 missile.

Edited January 11, 2019 by p1t1o

[kerbiloid]

2 hours ago, ARS said:

cannons of 300-400 mm caliber taking their place as heavy main gun

Long time ago, in a galaxy far-far away. WWI, post-WWI, still not carved post-WWI.

Btw in those days tanks had 40-90 mm.

So, both tanks and ships became ~120 mm more or less simultaneously.
(Old Soviet 115 mm and NATO 105 mm, modern Soviet/Russian 125 mm and NATO 120 mm, 127 mm naval)

***
Sturmtiger, 380 mm.

Spoiler

 

Edited January 11, 2019 by kerbiloid

[p1t1o]

1 hour ago, kerbiloid said:

Sturmtiger, 380 mm.

  Reveal hidden contents

 

That is actually a very good point and something I did not consider with my earlier response, it is literally a tank with battleship-calibre weapon!

However, not the right kind.

That particular 380mm weapon, amongst other of its contemporaries, could indeed be devastating against tanks (heck, even modern tanks, if using modern technology) with a shaped charge. But in reality they would be of very little anti-tank use. They are more closely related to mortars, have a very short (few hundred m) ranges, not really accurate enough to target vehicles (esp. moving ones, projectile too slow) and are designed for demolition of fortifications.

In my earlier comment I was imagining a 300mm kinetic anti-tank weapon, which would be huge, essentially identical to a 300mm battleship gun.

 

FunFact: 380mm projectile for Sturmtiger was rocket-assisted:

 

290mm "dustbin" projectile for Churchill AVRE (similar class of vehicle) :

 

 

Another FunFact - shaped charges are powerful, there exist today, shoulder-launched RPG variants that can penetrate frontal MBT armour.

https://www.telegraph.co.uk/news/uknews/1551418/MoD-kept-failure-of-best-tank-quiet.html

(no poop they kept it quiet, thats a no-brainer. "Hey enemies! This weapon can damage our tanks!")

IIRC the tank was actually missing its usually applique ERA panels on the front, which disagrees with this article, but I could be wrong/misremembering.

RPG-29, penetrated frontal armour of a Challenger II. However, internal effects were limited to partial destruction of drivers left foot, and more minor injuries to rest of crew.

Edited January 11, 2019 by p1t1o

[magnemoe]

3 hours ago, kerbiloid said:

Long time ago, in a galaxy far-far away. WWI, post-WWI, still not carved post-WWI.

Btw in those days tanks had 40-90 mm.

So, both tanks and ships became ~120 mm more or less simultaneously.
(Old Soviet 115 mm and NATO 105 mm, modern Soviet/Russian 125 mm and NATO 120 mm, 127 mm naval)

***
Sturmtiger, 380 mm.

  Reveal hidden contents

 

Yes and large guns was also used on land, including the larges gun ever used 
https://en.wikipedia.org/wiki/Schwerer_Gustav

On ground you have practical limit on how heavy something can be, it has to move around pretty fast it has to be able to cross bridges and similar. Engines during WW2 was also much weaker for their size. Some of the WW2 heavy tanks came up to this limit and modern main battle tanks are at it but engines are way better also bridges has been updated to handle heavy trucks but many 3rd world countries could not use M1 or Challenger efficient as to many bridges are to weak. 

You can build an very large ship, but you would have an hard time putting an schwerer gustav on one, yes an German leader wanted to do that but the navy had no problems with counter arguments. 
US largest artillery is 155 mm, Russia has 200 mm but its a bit to huge and the operation is an problem. Modern artillery has to be able to move shortly after firing as they will be shot back at. Russia also has an 240 mm mortar carrier. 
Russia has always focused more on artillery both cannons and rockets than the US who has relied more on air-power. 

US navy will start moving over to 155 mm guns on larger new ships, this is mostly as most of the work on smart shells is in 155 mm.
Going much larger and rockets are more practical, yes they are more bulky, another reason why navy want smart shells. On land simply having more trucks with rocket launchers often make more sense. 
 

[kerbiloid]

13 minutes ago, magnemoe said:

Russia also has an 240 mm mortar carrier. 

And meet 406 mm Kondensator (self-propelled howitzer) and 420 mm Transformator aka Oka (self-propelled mortar) (1957).
 

Spoiler

 

Their mine (750 kg, 45 km),

 

.
Other pikchaz.
http://alex-news.ru/rossijskoe-vpk-114/

Edited January 11, 2019 by kerbiloid

[magnemoe]

5 minutes ago, kerbiloid said:

And meet 406 mm Kondensator (self-propelled howitzer) and 420 mm Transformator aka Oka (self-propelled mortar) (1957).
 

  Hide contents

 

Their mine (750 kg, 45 km),

 

.
Other pikchaz.
http://alex-news.ru/rossijskoe-vpk-114/

Or the US gun who shot an nuke. The 200 and 240 mm was in use this century. 

Love the shell however so aerodynamic, and yes an option to railgun might simply be an larger caliber gun with discarding sabot. 
A shame the breach of the Iowa's was cracked or they might have outlasted the B52  
No I don't like the B52, they look like transports, all other bombers from B17 to B2 look cooler

[Gargamel]

14 hours ago, ARS said:

Why in land warfare...

It's just Newton's second law.   It's the mass of the vehicle that determines how big a gun you can carry.   A tank is heavy, but a battleship is even heavier, so they can carry even bigger guns.  So what would be a main gun on a ship would send a tank flying just shooting it, let alone being able to move the dang thing to start with.   So the bigger guns are consider the main weapons, regardless of the vehicle. 

 

[KG3]

10 hours ago, Gargamel said:

It's just Newton's second law.   It's the mass of the vehicle that determines how big a gun you can carry.   A tank is heavy, but a battleship is even heavier, so they can carry even bigger guns.  So what would be a main gun on a ship would send a tank flying just shooting it, let alone being able to move the dang thing to start with.   So the bigger guns are consider the main weapons, regardless of the vehicle. 

 

How about a recoilless riffle?  You can fire a relatively large gun from just a jeep, just don't be standing behind it when it goes off!  

[Lisias]

Is there a Add'On to automatically fill a craft with random generated tourists?

I'm aware that Ship Manifest allows creating "temporary" tourists, but I have to do it one by one and I have a airliner with 288 seats to fill! Something that would just "filler up" the empty seats with random generated tourists would be a plus!

Edited March 20, 2019 by Lisias
tasting my own medicine :)

[kerbiloid]

1 hour ago, KG3 said:

You can fire a relatively large gun from just a jeep, just don't be standing behind it when it goes off!  

So, put a 40 cm wide pipe at 2 meters height and get out from the tank to load it from back with a shell with double amount of powder because usually it has lower projectile initial speed.

Edited January 12, 2019 by kerbiloid

[KG3]

7 hours ago, kerbiloid said:

So, put a 40 cm wide pipe at 2 meters height and get out from the tank to load it from back with a shell with double amount of powder because usually it has lower projectile initial speed.

Well, I guess there is a reason they don't use recoilless riffles so much these days. 

[kerbiloid]

6 hours ago, KG3 said:

Well, I guess there is a reason they don't use recoilless riffles so much these days. 

As well as the pistol rocket-bullets from the sci-fi of 1950s.

[AlbertKermin]

Question- what is the orbital period for a stable  low polar orbit of Saturn's moon Titan?

I'm working on editing my second book, and my version of RSS is broken, so I can't double-check my numbers.

Edited January 13, 2019 by AlbertKermin

[kerbiloid]

15 hours ago, AlbertKermin said:

orbital period for a stable  low polar orbit of Saturn's moon Titan

T = 2 * pi * sqrt(R³ / (G * M)) = 2 * pi * sqrt(2574730³ / (6.67*10^-11 * 1.3452*10²³)) ~= 8666 s = 2^h24^m26^s

Edited January 14, 2019 by kerbiloid

[AlbertKermin]

5 hours ago, kerbiloid said:

T = 2 * pi * sqrt(R³ / (G * M)) = 2 * pi * sqrt(2574730^3 / (6.67*10^-11 * 1.3452*10²³)) ~= 8666 s = 2^h24^m26^s

Um- thanks? That's using the radius at the surface, not above the atmosphere, though.

[YNM]

23 minutes ago, AlbertKermin said:

Um- thanks? That's using the radius at the surface, not above the atmosphere, though.

Atmosphere thickness is roughly 1200 km, so multiply the surface value by about 1.3 .

[KG3]

On ‎1‎/‎13‎/‎2019 at 1:11 AM, kerbiloid said:

As well as the pistol rocket-bullets from the sci-fi of 1950s.

Those old Gyro-Jet bullets were awesome!   The only problem they really had was that if the target you were aiming at was close enough to hit (2-3 meters tops) the bullet would be going so slow that it would just bounce off.  At the distances it took for the bullet to reach lethal velocity it would be traveling in a very random direction!  

[p1t1o]

2 hours ago, KG3 said:

Those old Gyro-Jet bullets were awesome!   The only problem they really had was that if the target you were aiming at was close enough to hit (2-3 meters tops) the bullet would be going so slow that it would just bounce off.  At the distances it took for the bullet to reach lethal velocity it would be traveling in a very random direction!  

Its a sad thing almost. The first manufacturing run of the ammunition had a defect that compromised the thrust nozzles, meaning that all of the ammunition in existence had lacklustre performance and reduced accuracy (spin stabilised by angled rocket exhaust. Compromise the exhaust and you compromise the accuracy.) 

It was not uncommon for a round not even to make it to the end of the barrel as the weapons were re-cocked by the bullet as it was fired and with the below-spec thrust, they sometimes didnt manage it. (And yeah, I imagine you could put your hand over the barrel and stop it)

Unfortunately for rocket-gun enthusiasts, the under-performing weapon made so few sales, to nobody's surprise, that another manufacturing run on the ammunition was not feasible financially and the rocket-gun died behind a desk.

It did see some service in Vietnam though, and those who used it liked it alot. They admitted it had no power at close range, but the sound it made ("ZWIIIP" apparently) was unusual and hard to recognise, and did not originate from the shooter's location, meaning that your position was given away much less when firing, which I imagine is all the more important in jungle warfare.

[magnemoe]

56 minutes ago, p1t1o said:

Its a sad thing almost. The first manufacturing run of the ammunition had a defect that compromised the thrust nozzles, meaning that all of the ammunition in existence had lacklustre performance and reduced accuracy (spin stabilised by angled rocket exhaust. Compromise the exhaust and you compromise the accuracy.) 

It was not uncommon for a round not even to make it to the end of the barrel as the weapons were re-cocked by the bullet as it was fired and with the below-spec thrust, they sometimes didnt manage it. (And yeah, I imagine you could put your hand over the barrel and stop it)

Unfortunately for rocket-gun enthusiasts, the under-performing weapon made so few sales, to nobody's surprise, that another manufacturing run on the ammunition was not feasible financially and the rocket-gun died behind a desk.

It did see some service in Vietnam though, and those who used it liked it alot. They admitted it had no power at close range, but the sound it made ("ZWIIIP" apparently) was unusual and hard to recognise, and did not originate from the shooter's location, meaning that your position was given away much less when firing, which I imagine is all the more important in jungle warfare.

Yes its naturally pretty quite as no explosion. 
Thought it would be perfect for an grenade launcher. Much larger bullet and rocket so should be easier to make while hard to make them less accuracy at range and nothing you will shot at close range with anyway. No recoil. However the larger rocket might easy burn the shooter. 

[Gargamel]

On 1/12/2019 at 8:55 AM, KG3 said:

How about a recoilless riffle?  You can fire a relatively large gun from just a jeep, just don't be standing behind it when it goes off!  

Probably bumping an older question...   But there's a limit to how big of a gun that jeep can carry before it's suspension collapses.   On a battleship, they'd just use that gun to wake the crew in the morning....

[sh1pman]

6 hours ago, magnemoe said:

Yes its naturally pretty quite as no explosion. 
Thought it would be perfect for an grenade launcher. Much larger bullet and rocket so should be easier to make while hard to make them less accuracy at range and nothing you will shot at close range with anyway. No recoil. However the larger rocket might easy burn the shooter. 

Just think. .75 cal gyro-jet with explosives inside. Tungsten tip for armor penetration. Steel jacket to generate shrapnel upon explosion. Fired with full-auto machine gun.

[StrandedonEarth]

Speaking of Gyro-jet, rocket-propelled bullets, does anyone remember Runaway, from 1984?

Sorry about that, some people may have been trying to forget that turkey

[KG3]

1 hour ago, StrandedonEarth said:

Speaking of Gyro-jet, rocket-propelled bullets, does anyone remember Runaway, from 1984?

Sorry about that, some people may have been trying to forget that turkey

or better yet

[kerbiloid]

7 hours ago, sh1pman said:

.75 cal gyro-jet with explosives inside.

A three-staged pistol bullet. 1st stage - starter, 2nd - booster, 3rd - apogee in-flight corrections,

7 hours ago, sh1pman said:

Tungsten tip for armor penetration.

Forget the tungsten. Only uranium, only hardcore.

7 hours ago, StrandedonEarth said:

does anyone remember Runaway, from 1984?

It should have a "suspended stand-by" in-flight mode: to wait behind a corner until a target sticks the head out to have a look.