EMP pulse vs car.

[Nor_Cal_Grown]

Get a mechanically injected diesel. Zero electricity needed to run. If the starter dies, you can bump start it or use compressed air.

[Alaric]

Also, although I'd trust calgunners with darn near anything over the average civi, I'm still curious does anyone have any sources (i.e. books, articles, scientific journals, etc)?

Here's a good source: http://www.empcommission.org/reports.php

Although it's a novel, I also found the book One Second After to be very informative on this subject.

Regarding circuit breakers and surge protectors, common thinking is that they would be of no use to stop damage from an EMP because of the milliseconds it takes for them to trip. Apparently one of the aspects of an EMP is the speed at which it travels.

[IntoForever]

everything depends with EMP. You never know. However it is the electronics that are affected. Electromagnetic parts such as starters and relays will not be affected. However most alternators have voltage regulators that are microprocessor based. These could be fried. Many older cars have alternators with electromagnetic voltage regulators. These should be fine, So if you have a 1974 VW beetle, Your radio wont work but the car will run just fine.

So my truck and motorcycle are screwed, my '56 VW is safe.
I know someone who claims to have built a HERF gun, showed me schematics but he is 5150, homeless half the time and loony all the time so I don't believe him. Claims he's knocked out a car with it before.

[sholling]

Any active component will most likely be toast. It would likely depend on the design of the car's quasi finite state machine. I'm an electrical engineer but no automotive expert so I'm not sure how all the electrical components are tied together. But I would imagine there is some kind of 'safe to start' finite state machine that receives signals from sensors in the brake lines, engine temp, etc that determines its OK to start the car. These signals require a lot of conditioning to maintain their integrity from start to finish which requires a lot of circuity that could be damaged from EMP/EMI. I could be way off but that's how things are done in my industry, I assume its similar for the automotive industry.

That would be a modern computer controlled engine management system - you can fry the computer inside with a static charge that's barely noticeable to a human.

If you go back to a pre 1970 car technology with a 100-150 amp alternator or generator and calculate what it takes to fry that device, and what it takes to burn points (protected by the condenser) beyond use, and fry a condenser (a fairly beefy little capacitor) designed to absorb a good sized charge, or what it takes to fry a 20,000 volt coil, or fry a heavy duty starter solenoid found the a GM truck. I'm not saying it can't be done but I think you'd have to be so close that the driver doesn't need headlights because he already glows in the dark.

Open questions for everybody:

1. How did Professor Oppenheimer and General Farrell get home from the Trinity test?
2. How did the crew of Enola Gay get back to base?

Hint: They didn't walk.

[4acae86]

The poor mans solution is to find a pre 1974 truck with a coil and points. Unless the blast is close enough to melt the tires odds are it'll start. But keep a spare points and condenser just to be safe. Think about how much power it takes to blow 100 amp alternator or a starter solenoid.

That is how I keep my old 68 pickup.... it has an electronic ignition (aftermarket), but I keep points and a few tools in the truck. I also keep the battery when I am not driving it. I also keep a spare solenoid and distributor laying around.

[Alaric]

Open questions for everybody:

1. How did Professor Oppenheimer and General Farrell get home from the Trinity test?
2. How did the crew of Enola Gay get back to base?

Hint: They didn't walk.

Good questions, but a little misleading too. The bombs used on Japan were relatively low yield and not "tuned" for maximum EMP production, but rather for maximum physical damage. Nor were they dropped at very high altitude for maximum EMP coverage range, but again for maximum damage inflicted on the cities.

Some countries (Russia, China, Iran, the US) have all done R&D on EMP tuned nukes and incorporated them into their war plans. It's hypothesized that as few as two high-yield EMP tuned nukes detonated at high altitude in strategic locations over the US could effectively zap the entire country.

Suffice to say, yes, older tech is more resistant to EMP, but is not entirely immune either.

[GrizzlyGuy]

I know someone who claims to have built a HERF gun, showed me schematics but he is 5150, homeless half the time and loony all the time so I don't believe him. Claims he's knocked out a car with it before.

That's theoretically possible, is this his rig?



You can buy schematics, parts or fully assembled EMP/HERF generators here. Even a small one should be capable of knocking out a car's EFI computer if you were to open the hood and get very close to it. To do what they show in the video you'd need a lot more horsepower.

[anthonyca]

Get a mechanically injected diesel. Zero electricity needed to run. If the starter dies, you can bump start it or use compressed air.

I've got one. It will even run on waste vegetable oil.

[LMT4ME]

Good info on a mechanically injected diesel. Aren't the new was have electronic fuel injection? BTW a surge protector will not help the transient spike of an EMP is too fast.

[killmime1234]

Mechanically injected bio-diesel FTW?

So large capacitors are resistant to EMP it sounds like?

It has also just occurred to me what an investment a little pull-start two-seater go kart would be. The only thing I need are some spark plugs kept in the microwave!

And regarding:

Open questions for everybody:

1. How did Professor Oppenheimer and General Farrell get home from the Trinity test?
2. How did the crew of Enola Gay get back to base?

...from what I have read (this is from wikipedia so take it with a grain of salt), EMP "...only occurs within the severe blast radius for detonations below about 10 km altitude." So basically even if the cars around you still exist in this zone, you probably won't; and thus, my question pertains to the more practical situation in which a massive EMP is generated by an upper atmosphere detonation.

[LMT4ME]

Good questions, but a little misleading too. The bombs used on Japan were relatively low yield and not "tuned" for maximum EMP production, but rather for maximum physical damage. Nor were they dropped at very high altitude for maximum EMP coverage range, but again for maximum damage inflicted on the cities.

Some countries (Russia, China, Iran, the US) have all done R&D on EMP tuned nukes and incorporated them into their war plans. It's hypothesized that as few as two high-yield EMP tuned nukes detonated at high altitude in strategic locations over the US could effectively zap the entire country.

Suffice to say, yes, older tech is more resistant to EMP, but is not entirely immune either.

Low altitude nuke detonations (Hiroshima/Nagasaki /ICBMs etc) causes localized EMP. If a nuke is detonated 1km above the ground the EMP will only travel a very limited distances (several100s of miles). An EMP burst altitude of 400-600 km will travel thousand of miles. In addition, a high altitude burst will activate the ionosphere enhancing the effect. One burst above Wisconsin could take out most of the US. There was a US Congressional committee that looked into an EMP attack. It concluded that we are in good shape = kiss our a** goodbye. They promptly stopped reviewing the issue since there was no reasonable way of dealing with the scenario. Interestingly, other counties (India for example) has acknowledged a preemptive EMP strike as one it's most gravest concerns.

[sholling]

...from what I have read (this is from wikipedia so take it with a grain of salt), EMP "...only occurs within the severe blast radius for detonations below about 10 km altitude." So basically even if the cars around you still exist in this zone, you probably won't; and thus, my question pertains to the more practical situation in which a massive EMP is generated by an upper atmosphere detonation.

I'm a big believer in the threat of EMP and have endlessly debated those that claim it's overblown but I just don't see a mechanism for EMP damaging a pre-1970s car. Computer controlled devices and cars yes easily. Transformers and streetlights yes because tens or hundreds of thousands of miles of the electrical grid would act as a gigantic collection antenna.

The idea (no disrespect intended to anybody) of keeping spark plugs in a microwave to protect them from EMP is a great example of an overreaction. Spark plugs make their living turning a 10,000-150,000 volt charge from the coil into a spark. If it can handle that thousands of times a minute it'll deal with an EMP burst just fine. At worst keep a spare condenser and coil and be prepared in the very unlikely event that you need to hot wire and/or push start it. Better yet disconnect the battery and ground strap on the "TEOTWAWKI-mobile" and store it with the body/frame grounded.

I would expect to lose some or all of the electronics in the house, any portable electronics.

[maxicon]

This is a nearly impossible question to answer, though you could attack it statistically if you had the numbers.

An EMP's strength drops with distance and with a variety of other factors, so it's difficult to assume a field strength.

To be shielded, a part doesn't need to be completely enclosed by a Faraday cage, it only needs to be shielded from the pulse, which is traveling in a straight line (barring magnetic field disruptions and reflections), by the car's steel. For instance, sensitive parts under the hood are better protected than, say, a radio that could be seen through the window glass from the direction of the explosion, or dashboard components behind plastic.

Motorcycles are going to be in worse shape, since they have little steel around their control components.

To improve the survivability of pre-electronics cars, you could do simple stuff like shielding the coil and voltage regulator. Yes, the coil generates high voltage, but a pulse could induce high enough currents to burn the fine wires out if you were close, and a shield would be easy to make.

Spark plugs are not at risk, and most car wiring isn't either.

In other words, this is something that's almost impossible to plan against, except for some proactive shielding. How about a metallicized car cover? Anything that drops the pulse field strength will increase the odds of survivability.

[bohoki]

fear of emp is like being afraid of aliens and zombies

they only happen if a nuke is set of at high altitude

[stix213]

It depends upon shot placement

I lol'd