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Can the coil and capacitor (condenser) magneto/spark plug ignition system as exists on most general aviation aircraft survive an EMP? Let's talk about a standard Lycoming or Continental engine. How about most turbine engines? I'll use a PT-6 as an example. I assume the FADEC would be toast? How about other parts of the electrical system such as the battery? Is there any data or research on this?

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Can the coil and capacitor (condenser) magneto/spark plug ignition system as exists on most general aviation aircraft survive an EMP?

Like anything it depends on the EMP's strength, the angle of incident to the device and the device in question. The various things in an aircraft will break down for different reasons. But for the rest of this lets assume an EMP that is sufficient to fry stuff. A magneto will suffer toasted coils as the induced current could potentially generate enough heat to degrade the resin coating on the wire they use on coils. It should however be noted that the magneto is more than likely shielded to prevent interference with avionics which will play out in your favor here.

How about most turbine engines? I'll use a PT-6 as an example. I assume the FADEC would be toast?

Most likely yes. Again the unit is generally housed at least in some capacity in a shielded case but modern PCB components don't play nice with large induced currents. Turbines do have an Igniter system that may see some damage depending on the severity.

How about other parts of the electrical system such as the battery?

Things like interior lights will most likely blow out, batteries (depending on type and casing) could go. Overheating is a concern if enough current is forced over the line.

Is there any data or research on this?

There is some Mil-Specs (MIL-STD-1541 (USAF)) out there that cover it for the military. This question covers it for airliners. You can find at least one book on the topic here. There was a lot of research on this that pertains to missile systems as one anti-missile defense was to detonate a nuke in front of the oncoming unit. If the blast did not take it out the resulting EM field would fry what ever guidance and control systems were on board (assuming it was not ballistic). As such, work went into making the units EMP hardened. I'm not sure that work is very public though. The soviets were big users of vacuum tubes as they believed them to be far less susceptible to EMP's. It looks like this company does testing and research on EM hardened aircraft.

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Concerning ignition, and if no semiconductors are used (some capacitor-discharge systems use SCRs) there is little possibility of any damage, since coils, capacitors or mechanical switches can withstand very high transient currents.

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    $\begingroup$ Do you have any supporting data that explains this? I had exactly the same feeling but no data. $\endgroup$ – Pugz Jun 22 '17 at 11:01
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All electrical devices are susceptible to EMP to varying degrees. EMP causes a disruption in the electrical and magnetic field (see Wikipedia).

The magneto uses magnets and coils to generate AC pulses. When a strong magnetic or electric field passes through such a system excess current and voltage would likely be introduced and so a device who's operation depends on magnetic fields would likely falter (though maybe not fail) during a magnetic event.

One concern is that all discrete electric components have sub-components (usually insulation) that have a maximum breakdown voltage. The wires in a coil have a thin insulation on them to keep from shorting to other coils or the component body. A high voltage spike could cause that material to fail and create a short.

Another concern is that large currents amplified via transformers could cause other components (and even the transformers themselves) to fail like during the 1989 geomagnetic storm. In your aircraft a few critical items could cause a similar failure. The ignition coil could amplify current flow on the battery side of the system. While a fuse would likely blow in this scenario it's conceivable that a string of smaller pulses wouldn't trip the breaker and could damage the battery or other components on that system.

If a high voltage/high current system like a power station can be effected it seems likely that a close pulse to an aircraft would cause similar failure, or at least degradation, to discrete electrical components.

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    $\begingroup$ Transformers are vulnerable to geomagnetic storms because power lines make excellent antennas and pick up a lot of power. In the absence of large antennas, it's unlikely that simple components, like coils, will be damaged by EMP. $\endgroup$ – xxavier Jun 22 '17 at 15:07

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