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During the battle off the coast of Hong Kong, Leatherback emits an electromagnetic pulse

disabling Striker Eureka, and at least briefly, some of the systems at the Shatterdome, but not Gipsy Danger, as Gipsy is "analog" and apparently not affected by the EMP blast despite being at the Shatterdome where other electronics were shut affected.

How is this Jaeger different? It is nuclear powered, but like the other units, it is controlled by electronic systems. Nuclear or no, its systems should have been disabled like everything else.

eis
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phantom42
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  • I don't remember the scene that good anymore, but wasn't that jaeger powered down when the EMP blast was released? – LarissaGodzilla Oct 18 '13 at 14:05
  • @bumbumfish They don't specifically say if it was powered up or not at the time, but after the blast hits, Tendo and Stacker are talking about how they're out of options when Raleigh says that Gipsy was not affected because she was analog instead of digital. – phantom42 Oct 18 '13 at 14:09
  • well... in that case. Maybe it had extensive shielding against radiation. How else would the pilots live with a nuclear turbine under their feet? – LarissaGodzilla Oct 18 '13 at 14:15
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    "Gipsy was not affected because she was analog instead of digital." That alone is nonsense. In fact, digital chips with tiny circuit lengths are less affected by EMP than a longer circuit that carries an analog signal. Personally I thought it was a bit of a stretch that their earlier Jaeger was nuclear powered (as apparently was the Jaeger piloted by Stacker) yet a latter one was powered by ..50 diesel engines?!? – Andrew Thompson Nov 30 '13 at 02:41
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    Pacific Rim was a movie about giant robots punching monsters in the face. Don't think about the plot too hard, it isn't supposed to make sense. – Draco18s no longer trusts SE Jan 25 '16 at 20:41

4 Answers4

22

EMP disables digital transistor-based electronics, but old digital valve-computers are unaffected as they rely on ionised gas to control the gating instead of transistors. An analogue computer could similarly be immune to the effects of an EMP, depending what it was constructed out of.

Nick
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    +1: This is a good, textual explanation of the mechanics of how this could happen. Meta-textually, that part of the film could be read as a reference to Giant Robo. It's the same sort of angle: The newer, better energy source doesn't work because of interference by the enemy, but the heroes still have an older model giant robot at their disposal. – Matt LaFave Oct 18 '13 at 16:37
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    @MattLaFave It's a classic trope, used in many movies and stories in general, to explain why some older system is having an edge or why the protagonists are losing technology/advantages. Take Battlestar Galactica as an example. It's been the only Battlestar surviving (other than Pegasus), just because it's been too old to be affected. Side note: Wouldn't the Jaeger work as a cage, keeping the EMP out (see Faraday's Law)? – Mario Nov 24 '13 at 10:48
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    This is nonsense. The Americans thought the Russians were being very cleaver in using valves in Mig jet fighters, in order to try and counter EMP (operative word 'try'). Soviet sources later joked about this. The reason they used valves was 'cost/availability of new tech.'. Further, longer 'non-tube' circuits in the aircraft would be affected. So the valve based equipment - even if it still worked - would be relying on other circuits that would almost certainly fail. – Andrew Thompson Nov 30 '13 at 02:47
  • @Mario "Older Is Better" mentions both those cases. – Nick T Jul 12 '17 at 18:09
  • To users thinking of following @NickT's link: WARNING: TVTROPES. Your time is in danger. – Delioth Jul 12 '17 at 21:00
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Another possibility is that, on top of an ionised gas circuit, the Danger used steam valves and pneumatics, which worked on steam from its nuclear reactor, to move itself, rather than motors and electrical pump hydraulics. This would mean that if it got hit by an EMP, the ionised gas circuit would survive and there would be no effect on the actuators, as they are non-electric.

lfurini
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Kalium_Puceon
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0

This may be similar to the known "fly by wire" approaches used for the airplanes.

Some planes are "flown by wire" but are stable enough to be controlled by a human pilot without computer assistance. Such planes often have the "direct law" mode when the control is electric but not computer-mediated. As I understand, the simple electronics survived.

Differently, some military jet fighters are intentionally made "unstable", to be more agile. Such plane loses stability and crashes near immediately when a human pilot is left without continuous computer assistance. They have redundant computers, but if all are lost, such planes are not flyable.

Hence it seems possible to me that the older Gipsy has the "direct law" and can be operated without the computer assistance when the newer, faster and more agile Eureka lacks this capability.

h22
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A likelihood is that the writer just didn't know very much about what he was talking about. Here's my take. Gipsy was powered down, and the "solid iron hull, no alloys" may have allowed for some sort of EMP hardening. I don't know. But, to serve the purpose of "America saves the Day" she was unaffected.

As for the "Fifty diesel engines per muscle strand" part, I think they were talking about equivalent horsepower. Crimson Typhoon, the three armed chinese Jaeger was described with that quote. I think that the reactor was generating enough power from it's reactor to be equivalent to fifty diesel engines. As we saw in the intro where an early pilot is rigged up clenching his fist and in the background we see an unarmored prototype Jaeger arm match his movements, there are cable mechanisms. So those are probably said muscle strands, meaning lots of horsepower, perfect for face-punching.

armorhide406
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