AT-AT "maximum firepower"

[SylasGaunt]

I think the explosion was the generator blowing up not the laser bolt.
It doesn't make sense that full power shots would be 130kt when the normal shots couldn't have been much more than a gigajoule judging by various ground impacts. If the AT lasers were really so powerful they could of wiped out the trench line in one shot.

There is a reason why artillery normally uses a bunch of 155mm airbursts or DPICM shells against exposed infantry rather then firing one shell from a 280mm nuclear artillery piece or a 600mm mortar.

Because then the other side starts throwing nukes back at you. The rebel infantry were exposed, a low kiloton blast into the middle of their position should have pretty well wiped out the defenses altoghether.

[Darth PhysBod]

SylasGaunt; I dont care to speculate as to why General Veers didnt fire maximum firepower shots into the rebel defence. Who knows? who cares? it has no relevence, its a red-herring. All I'm interested in is scaling the pretty fireball(s) and therefore how much energy is involved.

[Darth PhysBod]

Hey Evil S'tan, could you do some work on these pictures? Or you could check them out on your own copy of TESB:

Probably a couple pounds worth or so, depending on what the special effects coordinator/safety guy let them play with that day .
Seriously those appear in the live action filmed on location (in Norway?), they would have had to be pretty small for the safety of the extras.

[Sea Skimmer]

Hey Evil S'tan, could you do some work on these pictures? Or you could check them out on your own copy of TESB:

Probably a couple pounds worth or so, depending on what the special effects coordinator/safety guy let them play with that day .
Seriously those appear in the live action filmed on location (in Norway?), they would have had to be pretty small for the safety of the extras.

Unlikely there was more then an ounce of explosives as a detonator, if any. Those are gasoline explosions, which is what's used by special effects crews for most blasts.

A couple pounds of explosives wouldn't give you a fireball like that.

[Sea Skimmer]

I think the explosion was the generator blowing up not the laser bolt.
It doesn't make sense that full power shots would be 130kt when the normal shots couldn't have been much more than a gigajoule judging by various ground impacts. If the AT lasers were really so powerful they could of wiped out the trench line in one shot.

There is a reason why artillery normally uses a bunch of 155mm airbursts or DPICM shells against exposed infantry rather then firing one shell from a 280mm nuclear artillery piece or a 600mm mortar.

Because then the other side starts throwing nukes back at you. The rebel infantry were exposed, a low kiloton blast into the middle of their position should have pretty well wiped out the defenses altoghether.

Actually its because its totally unnecessary, notice how you don't address the point of very large conventional guns being used against soft targets in combat. Veer's fire worked perfectly fine, shattering the defence and allowing for a steady advance. Additional fire was unneeded.

Indeed while many Rebels ran off, that's an advantage if anything. They would have little chance of escaping but would proved useful personal for show trials, interrogation and torture driod calibration.

[Ender]

I find it ammusing that people are so used to challenging ICS by using the "Well why didn't they use the 200 GT here? or Here?" and looking to tear into rationalizations that when presented with calcs from the movies, they still fall into habit of using the old method of attack.

Refute the assumptions of the calcs or challenge the math if you are going to go after this.

[Howedar]

It seems plausible to me that the Rebel defensive positions were powered by the generator (or the generator allowed them to fire at higher power). Firing on the generator would neutralize the defenses in one fell swoop.

[Darth Wong]

Let's get something straight, Sylas: the "why didn't they use it here?" argument is a valid rebuttal for theories about high firepower. It is not a valid rebuttal for observations of high firepower. Think about this. By your "logic", we can refute Hiroshima's firepower by noting that bombs dropped in Vietnam were clearly in the sub-kiloton range

Also: their mission was to destroy the shield generator SO THAT VADER COULD LAND TROOPS. If they just wanted to kill all the Rebels, they could have done that in myriad other ways, such as simply shooting at the base instead of the generator. But in case you were too stupid to figure out the plot of the film, Vader wanted prisoners.

[SylasGaunt]

You are trying to generate doubt by pointing out what you see as inconsistencies, but these inconsistencies are hardly of the "scientific impossibility" magnitude, and you fail to provide a consistent alternate hypothesis.

Explain what this line of questioning is supposed to prove. Are you trying to prove that the guns were weak? Too bad you can't explain the size of the initial blast, then.

Actually no. There's nothing wrong with the math that I can see so it's not that I'm questioning.

Are you trying to prove that they were being stupid? The front-line was a minor nuisance to them; why waste max-firepower blasts (for which you don't know the recharge time) on units that are not a threat?

Suppose the use of this blast drains their weapons for a while? Wouldn't it be stupid to use it on anything other than the primary target, particularly when you're being harassed by local air support?

A shot like that into the Speeders when they were launching probably would have solved that problem. If Veers only had one AT-AT I could see him witholding but I seem to recall him having at least 3, maybe four (been a while since I've seen ESB).

From what we see of other Imperial officers arrogant would probably be a better word to use than stupidity.

You are trying to generate doubt by pointing out what you see as inconsistencies, but these inconsistencies are hardly of the "scientific impossibility" magnitude, and you fail to provide a consistent alternate hypothesis.

As I said, there's nothing wrong with the math that I can see. And ES seems to have covered it pretty well.

Evil S'tan: I'm not sure if you covered this but the second fireball seems to, in the video clip supplied, form from two fireballs merging toghether. I'd get a screencap but Media player won't let me see the video if I turn my hardware acceleration down to get one. Mind taking a look at that?

[SylasGaunt]

NM no screencap needed you can see it in pic 7

[His Divine Shadow]

Here are some comments from SB, I decided to post them here, with Shrike's permission.

You know, I find that scaling sort of hard to believe, given that the alleged 3+ megaton fireball does not produce a mushroom cloud. A nuclear groundburst will create a mushroom cloud, so why wouldn't a megaton-level explosion from a blaster shot?

http://nuketesting.enviroweb.org/hew/Nwfaq/Nfaq5.html

Interesting how all the rebels should be getting at least first (and quite possibly up to third) degree burns from the large explosion. Plus they'd then get knocked over by the 2-3 PSI shockwave. But where's the shockwave? Hoth is covered in blown snow, even a 16 kT explosion should have a highly visible shockwave, never mind that of a 130 kT or even a 3.4 MT detonation.

You know, I find that scaling sort of hard to believe, given that the alleged 3+ megaton fireball does not produce a mushroom cloud. A nuclear groundburst will create a mushroom cloud, so why wouldn't a megaton-level explosion from a blaster shot?

Actually you don't get to see the explosion long enough for it to form into a mushroom shaped cloud

The closest we get is this:
<image>

shortly after this scene, the video cuts to Han and Leia inside the base and you never get to see the fireball fully develope into a mushroom cloud.

Interesting how all the rebels should be getting at least first (and quite possibly up to third) degree burns from the large explosion. Plus they'd then get knocked over by the 2-3 PSI shockwave. But where's the shockwave? Hoth is covered in blown snow, even a 16 kT explosion should have a highly visible shockwave, never mind that of a 130 kT or even a 3.4 MT detonation

They probably are geting burned. But they are also in sub zero temperature environment and are fully dressed in winter clothing. Their faces are likely burned though but you only catch a glimps of them running away and you never actually see what happens to them from a frontal viewpoint.

Plus we don't see the explosion long enough to see its full effects. The shockwave wouldn't reach them instantly and we only see them running when the blast first occurs and not enough time after the blast to see them get the full force of the explosion.

You should get something from the first blasts though. More than a flash anyhow.

[His Divine Shadow]

Oh, a followup:

They probably are geting burned. But they are also in sub zero temperature environment and are fully dressed in winter clothing. Their faces are likely burned though but you only catch a glimps of them running away and you never actually see what happens to them from a frontal viewpoint.

Actually I threw that out as more of an interesting point, I didn't consider it worth following up on for exactly the reasons you posted. I just thought you guys might find the long term effects worth noting. Anyhow, a giant flash should have had the rebels instinctively throwing their arms up to shield their faces, turning away, etc, as they were facing directly towards the generator when it blew.

[Galaxy]

I don't understand how the distance is figured at more than 17km.

[Boba Fett]

It seems plausible to me that the Rebel defensive positions were powered by the generator (or the generator allowed them to fire at higher power). Firing on the generator would neutralize the defenses in one fell swoop.

What?

Maybe I misunderstand you but both the Golan DF.9/B anti-infantry tower and the Atgar 1.4 FD P-tower has it's own generators just like E-WEBs.

The generator itself was only responsible for the shield, that's why they call it shield generator.

[Spanky The Dolphin]

I don't understand how the distance is figured at more than 17km.

Veers: "Distance to power generator?"

AT-AT Pilot: "One seven decimal two eight."

[Boba Fett]

I don't understand how the distance is figured at more than 17km.

Veers: "Distance to power generator?"

AT-AT Pilot: "One seven decimal two eight."

I never knew SW is SI compatible...

[Galaxy]

oh i guess i missed that part

[Darth PhysBod]

I really dont see a problem with the size of the generator deduced (1.8Km) and thus the explosions:
The reactor on an ISD is 140m across, that on the Executor is probably around 1.5Km across and we know that the Rebel generator on Hoth was capable of holding off any attack from the entire Death squadron.

[Darth Wong]

Where did this 3 megaton figure come from? I thought we were talking about kiloton-range, which is hardly unreasonable for the obliteration of a structure more than a kilometre long.

[Connor MacLeod]

Where did this 3 megaton figure come from? I thought we were talking about kiloton-range, which is hardly unreasonable for the obliteration of a structure more than a kilometre long.

That was the third assumption, and it was clarified that it only applies IF the explosion was not the result of the generator exploding.

[Connor MacLeod]

Err.. explosion was rated at 6.8 MT due to size - 3.4 per gun I think for the max power volley.

I agree t hough, tht the MT range sounds too high

[Darth PhysBod]

Where did this 3 megaton figure come from? I thought we were talking about kiloton-range, which is hardly unreasonable for the obliteration of a structure more than a kilometre long.

We are talking about kiloton range yield for the bolts, the megaton figure (6.comes from scaling the fireball in the last pic which is much larger (~6Km), but then it is a secondary explosion.

[Darth PhysBod]

Err.. explosion was rated at 6.8 MT due to size - 3.4 per gun I think for the max power volley.

I agree t hough, tht the MT range sounds too high

Its more likely that final explosion is due to the generator exploding, I did say that, but people at sb.com seem to have fixated on that rather than the more likely kiloton range yield for the bolts.

[Connor MacLeod]

Additional notes:

http://www.theforce.net/swtc/walkers.html#atat


That gives stats on the AT-AT. We know they have a top speed of 60 km/hr , or almost 17 m/s. Saxton seems to indicate that the walkers moved 10 meters per step every second, which might help clarify things.

[Darth PhysBod]

Its more likely that final explosion is due to the generator exploding, I did say that, but people at sb.com seem to have fixated on that rather than the more likely kiloton range yield for the bolts.

Sorry that's incorrect, I didnt actually make that clear in the inital post when I've checked, I said:

" It is not clear weather or not this is due to the generator cooking off or the result of the AT-AT shots.If it is the generator cooking off why the relatively small explosion? after all this generator was capable of holding off any bombardment from the entire Death Squadron."

followed by:

"...and possibly as high as 3.4 MT per bolt if the final fireball was not the result of the generator 'cooking off'."

I should have made it clear I think its more likely the final explosion is the result of the generator exploding and not as a result of the bolts impacting.