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Jefffar wrote:The use of the big guns in AA role was mostly to try to break up an incoming air attack. The time of flight meant that all but the luckiest of shots would be not close enough to damage an individual aircraft, but a volley of big shells bursting amoung an incoming squadron would likely do a considerable amount of damage (note that most of the target aircraft were actually metal, but so thin skinned that the Japanese style incindiary shells could expect to have a chance of ignighting the fuel tanks).

I have never stated San Shiki shells were effective. My link is actually US trajectory tables of 16" high capacity high explosive shells.

This goes back to wether or not a Mac II was a capable anti air platform.

obsessed wrote:This goes back to wether or not a Mac II was a capable anti air platform.

Was the HWR-00-Mk.II Monster technically capable of anti-aircraft fire? Yes.

As powerful and long-ranged as its guns are, it should have no trouble reaching aircraft flying at altitudes well above the domain of normal combat aircraft and reach those altitudes at distances of close to 100km.

The OSM spec. for the HWR-00-Mk.II Monster has four acknowledged types of shells... the most common being variable-yield thermonuclear reaction shells, but also including high-explosive, armor-piercing, and anti-aircraft shells.

Is it an effective anti-aircraft platform? No. It doesn't have enough ammunition for a sustained defense, and it doesn't have the mobility or elevation capability to confront aircraft that are maneuvering or flying at close range.

It's not designed to be an anti-aircraft platform. It if was, it would be designated a Surface Defense Robot or Air Defense Robot. What it's designed to do is punch variable yield reaction warheads into enemy ships and formations at considerable distance... be they in the air or on the ground.

R Ditto wrote: ...
A 406mm HE shell is roughly 2000 pounds IIRC, and even if just 1,000 pounds of that was HE, ...
I also think of how 406mm shells tend to leave 50ft wide blast craters in the ground.

I am not an explosives expert, but have been researching military and explosives SO MUCH in the last 15 years, I MUST be on FBI watchlists.

Anyway, the 1930s and 1960s stockpile 406mm shells did not carry the weights of explosive you presented. The 50 foot crater is correct (15 meters wide and 6 meters deep) when the AP shell struck concrete.

Well known data for the Mark 13 or 14 406mm high capacity shell weighed 862 kg and packed 69.66 kg of Comp B. There are NO published blast radius of the HC round. Questionable data says 200 yard frag radius. There's also a website stating that a german tiger tank was flipped on its side from a near impact. Even the HC blew from 3 to 4 meters concrete depending on range out to 38 km.

The Mark 8 Armor Piercing round weighed 1225 kg with 18.55 kg of Comp B. It would penetrate from 8 meters concrete at 9 km to 4.6 meters concrete at 38 km. Its ARMOR penetration was 664 mm at 9 km, and 241 mm at 38 km.

I can not find any data on US 406mm number of fragments, or their weight or their velocity, but I did find data on German 380mm HC shells which were 800 kg with 64.25 kg of explosive filler. (TECHNICAL REPORT No. 372-45 GERMAN FIRE EFFECT TABLES August 1945 http://www.kbismarck.com/german-fire-effect-tables.html )

One cannot simply scale 127mm naval or 155mm howitzer shells up to 406mm, although I wish it were that simple. The 406mm HC shell carried enough Comp B that CONCUSSION over-pressure alone:
- 69 kpa (10 psi) at 16.5 meter radius,
- 28 kpa (4 psi) at 27.6 meter radius,
- 14 kpa (2 psi) at 44.4 meter radius,
- 6 kpa (1psi) out to 86 meter radius,

See http://en.m.wikipedia.org/wiki/Effects_ ... explosions (see direct effects) or http://en.m.wikipedia.org/wiki/Overpressure for what sort of damage would be inflicted.

Note: these blast overpressure estimates for the 406mm HC do NOT take into affect the fragments. Again, no proper data is available.

obsessed wrote:Well known data for the Mark 13 or 14 406mm high capacity shell weighed 862 kg and packed 69.66 kg of Comp B. There are NO published blast radius of the HC round. Questionable data says 200 yard frag radius.

Either way, any comparison to World War II-era military hardware is horrifically ill-advised when trying to estimate the capabilities of the Monster's 40cm cannons. Technology's come a long, LONG way since Mk.7 Naval Gun in the modern world, to say nothing of the Robotech world (or the Macross world, a setting even more advanced than Robotech).

After all, the Viggers 40cm liquid-cooled cannons mounted on the production models of the HWR-00 series destroids boast a maximum range more than four times that of the Mk.7 16 inch naval gun (160km vs the Mk.7's 38km). I can't find any figures for the Mk.7's margin of error at maximum range, but the Monster has its listed at less than 10m.

Seto Kaiba wrote: ...
Either way, any comparison to World War II-era military hardware is horrifically ill-advised when trying to estimate the capabilities of the Monster's 40cm cannons. Technology's come a long, LONG way since Mk.7 Naval Gun in the modern world, to say nothing of the Robotech world (or the Macross world, a setting even more advanced than Robotech).
...

Sorry, I get long-winded.

Blast Radius:
I am saying EVEN the ancient 1930s HC shell has enough Comp B explosive to inflict 69 kpa (10 psi) at 16.5 meter radius. That's 54 feet, meaning 20 foot RPG blast radius is too low in my opinion.

Yes, if the Comp-B were replaced with more powerful explosives, the blast radius and fragment range would increase.

Accuracy:
Even dumb 16" rounds land within a 200 yard box.
Laser guidance gives a CEP of 10 m. GPS guidance under 5 m.

A 1939 16" AP round cost $500 (estimate $8,500 inflation cost). Adding laser guidance kits to mortars, artillery, even bombs costs between $7,000, $15,000 to $22,000.

By contrast already designed laser guided copperhead 155mm costs $33,000 per shell. An excaliber 155mm costs $55,000 per shell.

http://forum.worldofwarships.com/index. ... ge__st__60
http://www.ww2f.com/topic/43340-bb-main-gun-accuracy/

obsessed wrote:I am saying EVEN the ancient 1930s HC shell has enough Comp B explosive to inflict 69 kpa (10 psi) at 16.5 meter radius. That's 54 feet, meaning 20 foot RPG blast radius is too low in my opinion.

Brother, EVERYTHING in the RPG is off in one direction or the other... you're not s'much preaching to the choir as you are the college of cardinals.

Virtually everything in the Macross Saga book is shortchanged, and virtually everything in the Masters and New Generation books is overstated. That's just the nature of the beast. I'd expect quite a bit more from the ridiculously advanced and powerful explosives the range alone tells us must exist. 'course, if they'd kept the Macross 'verse's reaction shells for it, we'd be looking at blast radii measured in kilometers. (.26km fireball radius, .6km 20psi+ air blast radius, 1.25km 5psi+ air blast radius for the shells used on the Mk.IP-type.)

obsessed wrote:Even dumb 16" rounds land within a 200 yard box.
Laser guidance gives a CEP of 10 m. GPS guidance under 5 m.

's that at maximum range, or nominal effective range?

Admittedly, even getting within 10m of the target from 160km away is pretty damned impressive for an artillery piece.

Iowa class battleship, 16 rounds shot at 25,000 yatds (22.6 km), 50% of rounds landing inside a 200 x 200 yard box.
16 rounds shot at 36,000 yards (32.9 km), only 3 rounds landed inside the box. That's 18.75%

Why fire a puny laser guided SRM, when you can send 800 kg of 16" shell ? All you need is a laser designator 650 feet to 12 mile range (198 m to 19 km).

And I'm going to keep ignoring this 160km artillery nonesense

Note: A CEP of 10 m means 50% of round land within 10m, 43 % land from 10 to 20m, and 7% land from 20 to 30m. Also 0.2% land outside 30m.

obsessed wrote:Why fire a puny laser guided SRM, when you can send 800 kg of 16" shell ?

Why send a 16" 800kg HE shell when you can send what amounts to a radiation-free mini-nuke and do far more damage to the enemy? Why wait until the enemy is 32km or closer? Why not send it from a couple hundred kilometers away?

obsessed wrote:And I'm going to keep ignoring this 160km artillery nonesense

's the official spec for the HWR-00-Mk.II Monster's 40cm guns... it's what the original creators put down as their range in the original Macross's production materials, and what the RT2E RPG says the range for the guns is (because they copied from the OSM).

Mind you, those 40cm cannons are also the Monster's shortest-ranged weapon... those Raytheon LSSN-20G missile launchers have a 300km+ range.

Seto Kaiba wrote:...
Mind you, those 40cm cannons are also the Monster's shortest-ranged weapon... those Raytheon LSSN-20G missile launchers have a 300km+ range.

I never did understand Monster guns versus missiles. Even modern AIM-54 carries a 61 kg warhead 190km. Using LRM damage table works, but blast radius is still low.

I am still working on a viable 406mm blast radius. Yes, based on physics. Don't hate me.

obsessed wrote:I never did understand Monster guns versus missiles. Even modern AIM-54 carries a 61 kg warhead 190km. Using LRM damage table works, but blast radius is still low.

Palladium's missile table is a big load of nonsense most of the time for Robotech and Macross, and the damage values assigned to guns often seem to be completely arbitrary. It's one of the reasons a straightforward effort to create errata for the Macross II book turned into a near-complete rewriting of the entire book.

They NERF a lot of stuff... the Monster got hit pretty bad with the wiffle bat.

obsessed wrote:I am still working on a viable 406mm blast radius. Yes, based on physics. Don't hate me.

'kay! My blast radii for the reaction warheads the Mk.IP used are also projected using real physics and the known blast yield of the shells.

Palladium has always hedged things towards Player Character survivability in order to keep the campaign going. Rules which make it possible to quickly kill characters are generally labelled as optional.

Jefffar wrote:Palladium has always hedged things towards Player Character survivability in order to keep the campaign going. Rules which make it possible to quickly kill characters are generally labelled as optional.

Which is one of the reasons the Monster entry makes so little sense... one of the things that got NERFed the worst was its survivability. It got demoted from "armored well enough to resist a near-miss with a nuclear warhead, no problem" to "armored with cake, crepe paper, and wishful thinking".

PCs aren't expected to use MACs, but they may have to kill one.

Jefffar wrote:PCs aren't expected to use MACs, but they may have to kill one.

With what, harsh language? It's no threat if the bloody thing can be taken down easily... and writing the game with the assumption that people WOULDN'T use one of its signature designs is just bad practice.

Seto Kaiba wrote:

Jefffar wrote:PCs aren't expected to use MACs, but they may have to kill one.

With what, harsh language? It's no threat if the bloody thing can be taken down easily... and writing the game with the assumption that people WOULDN'T use one of its signature designs is just bad practice.

Equally bad practice would be to make something that has a "I win button" for its main weapon.
And stopping MAC II's is pretty easy you use missiles the go to weapon of choice for causing destruction.

Still... The 160 km 40cm gun range sounds like Bull. Sounds like they literally took the range from Gerrald Bull's "project HARP".

It fired a 170 mm 180kg sabot round at 3600 m/s from a 16"/100 barrel (that's FOUR times the muzzle velocity of the naval 16"/50).

Bull I say... Bull

actually you can reach 40+ miles with a 155mm if you have rocket boosted shells.

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

http://en.wikipedia.org/wiki/Rocket-assisted_projectile

http://www.globalsecurity.org/military/ ... ns/rap.htm



however 100miles/160 km might be stretching it for 20th century derived tech.

obsessed wrote:Still... The 160 km 40cm gun range sounds like Bull. Sounds like they literally took the range from Gerrald Bull's "project HARP".

It fired a 170 mm 180kg sabot round at 3600 m/s from a 16"/100 barrel (that's FOUR times the muzzle velocity of the naval 16"/50).

Bull I say... Bull

I don't see why it would be bull. The German's Paris Gun type (WW1) has a demonstrated range of 130km, and is in the 200mm class (so smaller than the 400mm of the Monster).

Then there are various proposals for launching unmanned payloads into space with "canons", which means they have to reach a specific altitude (160km and travel nearly 5km per second at minimum). Now these are much bigger than a Monster, but it shows that cannons are at least theoretically capable of the job. And the HARP sent an object into suborbital flight regime (for the altitude listed its speed was insufficient to be considered in orbit)

No one has a sense of humour? I was making a pun http://www.google.ca/url?q=http://en.m. ... vE7YUk6AxA

The over 160km soulds exactly like they took Bull's gun range as Mac II.

Still no one gets the joke? ... no one? Bahahahaha

P.S. Railway guns fired from 15 shots per hour (1 shot every 4 mins), to 2 shots per hour (1 every 30 mins). Sure, fire a Mac II salvo 170mm reduced bore sabot round 160 km, wait over 40 seconds ( THREE melees until time on target). Oh, and you're sitting out the NEXT SIXTEEN melees because you're reloading... Good luck!

Okay, this is the last time I will post about 40cm blast radius: 40 feet
(11.5 meters rounded up) per shell

Actual defined 406cm blast damage from 69.66kg Comp B:
- 11.5 meters radius / 20 psi / Concrete demolished / near 100% troops killed (internal organ rupture, ear drum rupture, many torn off limbs)
- 16.5 meters radius / 10 psi / Concrete heavily damaged / nearly 50% fatalities / force will knock troops off their feet (or off rooftops)
- 24.5 meters radius / 5 psi / brick buildings collapse / fatalities and universal injuries (hit by building debris and concussion blast)
- 33.4 meters radius / 3 psi / wood buildings destroyed / troop serious injuries (some fatalities begin)
- 44.5 meters radius / 2 psi / moderate damage brick and wood buildings / flying debris wounds troops
- 86 meters radius / 1 psi / broken windows

BLAST RADIUS will mostly affect light MDC targets (aircraft, missiles, troops in body armor) and SDC targets (troops in the open, buildings, bridges). A single 33mm steel armor is enough protection. Anything above an APC carries over 33mm, even spaced, ceramic, composite, and even thicker RHA. A main body of mecha could not be penetrated, but sensors, exposed missile pods, antenna, spotlights, etc, will take heavy concussion damage. There simply isn't enough fragment mass nor kinetic energy to fully penetrate armor.

The bredth or width of most mecha is approx 10 meters, 15 meters for Zendraedi, and 24 meters for a Mac II. Units would not be close enough to receive damage (Modern tank doctine has a platoon moving 50 yards between tanks to reduce casualties FM 17-30)

A salvo from all 4 barrels would still disperse each round within the CEP area, within the 38 km range. Laser guidance still a good game addition for a 10 meter CEP as long as the target is illuminated by a laser designator.

Happy game play to all.