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The incredibly bad, postapocalyptic tv series Revolution begins with a mysterious event that causes all electrical systems to fail all over the globe. Even batteries don't work anymore.

In the first episode, after the "event" airplanes immediately start falling out of the sky in flat spins.

This had me thinking: which airplanes could survive an EMP-type event (FN1) that fries all electronics and renders electrical systems unusable? This means that even RATs would not be a viable choice.

Piper cubs and other single-engine planes with purely mechanical linkages could still keep on gliding and land safely.

I don't think any large airliner currently flying could make it. Could even a B-17 or DC-10 make it with no powered electrical systems -- just on unpowered hydraulics alone?

Bonus question: if they did fall out of the sky, I'm assuming it would be in lawn dart mode and not in flat spins?

Footnote 1: While the apocalypse event in Revolution turns out to not be an EMP, you can assume it was something similar for the purpose of this question.

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    $\begingroup$ For what it's worth, the 727 had a manual reversion system for the control surfaces in case of hydraulic failure. The 747-100 and -200 required hydraulics, but the hydraulic valving was controlled by cabling, not electronics. $\endgroup$ – Terry Dec 20 '14 at 4:06
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    $\begingroup$ @Radu094 Technically speaking, Air Force One does not designate a given airframe, but any USAF aircraft with the President aboard. Usually, of course, it's one of the two 747-200s, tail numbers SAM28000 and SAM29000. The SAM stands for Special Air Mission as I recall. $\endgroup$ – Terry Dec 20 '14 at 9:13
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    $\begingroup$ @Terry They actually did get that right toward the end of the movie. "Liberty Two Four is changing call signs - Liberty Two Four is now Air Force One!" $\endgroup$ – a CVn Dec 20 '14 at 16:52
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    $\begingroup$ @Kevin I expect the radios would be able to couple the pulse to at least a few other sensitive systems (autopilot & FMC at the very least) - the antennas make nice penetrations in the skin's pulse shielding ability (as do the windows). We could just borrow someone's A-380 for a low-altitude flyby of the Navy's EMPRESS antenna and zap it to test though :) $\endgroup$ – voretaq7 Dec 21 '14 at 6:06
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    $\begingroup$ One suggestion to make the question more clear: Since the event in Revolution had nothing to do with an EMP, it would be good to drop the reference to the tv show completely, or on he other hand, drop the reference to EMP if you want to know what happens when all electrical energy ceases to exist. The answers are different for the two scenarios and are muddying up the answers. $\endgroup$ – Lnafziger Dec 22 '14 at 1:06
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Older airliners use hydraulics and cables attached to the pilot controls. Some RATs power the hydraulics directly as well so limited control is still possible then. The pilots would get a workout but the plane would safely touch down.

However planes with entirely fly-by-wire systems (no current airliner is completely fly-by-wire) will be completely uncontrollable apart from shifting weight and would glide to the ground. They are made stable so they won't just enter a spin and pancake into the ground.

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  • $\begingroup$ "They are made stable so they won't just enter a spin and pancake into the ground." - does this mean they will default into a glide and land on their belly and not just lawn dart? $\endgroup$ – RoboKaren Dec 20 '14 at 3:44
  • $\begingroup$ @RoboKaren yes, it's because the horizontal stabilizers will pitch the plane up when it speeds up and down when it slows down leading to a stable glide path. $\endgroup$ – ratchet freak Dec 20 '14 at 4:17
  • $\begingroup$ A stable glide to earth sounds potentially survivable in a good number of cases, yeah? $\endgroup$ – raptortech97 Dec 20 '14 at 4:31
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    $\begingroup$ @raptortech97 There are cases where light aircraft with an unconscious pilot ran out of fuel and basically landed themselves in a field, with the pilot walking away with only a few cuts and bruises. Such a nice outcome is by no means guaranteed, but if circumstances conspire to give the plane a nice flat landing area with no mountains or trees to crash into "just gliding into the ground" is eminently survivable. $\endgroup$ – voretaq7 Dec 20 '14 at 5:12
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    $\begingroup$ All Airbus aircraft are demonstrated controllable with complete electrical failure. They would be pretty difficult to land if the electronics didn't at least partially recover (because the backup only allows controlling pitch and yaw and roll only via yaw-roll stability), but it would still be possible. Well, they probably don't count as "completely fly-by-wire" then; only some fighters do (that are fitted with ejection seats too) do. $\endgroup$ – Jan Hudec Dec 21 '14 at 21:38
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Well the key to an airliner (or any other vehicle) surviving a real EMP would be having engines and flight control systems that don't require any kind of computer assistance. Hydraulic control systems powered directly by the engine and not relying on a computer to operate the valves would continue to function, as would cable-driven control systems. Simple electric motors may also continue to operate (larger motors tend to be EMP-resistant, in smaller motors there's a chance the EMP could burn out the windings or arc over and destroy the brushes) which means we can assume you'd still be able to pump fuel into the engines of most jet airliners.

Thinking along those lines I imagine the remaining DC-3 fleet would be almost entirely unfazed by an EMP (save for any retrofitted avionics, radios, etc. which would likely be fried). Similarly the Boeing 707 would probably not have a problem, nor would early-generation DC-9s, 727s, and 747s - you would lose any retrofitted flight management computers, but they are generally not essential to operation in the earlier-generation aircraft.
There are probably several other models still in service (or hanging around various boneyards) which are at least somewhat EMP-resistent.


If we assume a Revolution-style apocalypse where absolutely nothing using electricity works you're rather worse off: only aircraft which have cable-driven controls (or hydraulic backups with manual valve actuation & direct pressurization from the ram air turbine) would have functional flight controls. Thats a much smaller subset of the fleet these days, but the planes do exist - as Terry pointed out the 727 and 747 both have non-electric control systems available.

If we assume magnetos can still generate a spark the DC-3 other planes of its generation would be the clear winner: The engines would continue to run until stopped (the engine-driven fuel pumps would continue to feed the engine fuel). Aircraft like this could even possibly be restarted (using shotgun starters or pull starters, and a little help getting fuel to the engine until the mechanical fuel pump could take up the job).
If we assume magnetos would also stop working then at least you'd have flight controls and the ability to make a controlled emergency landing somewhere as you could in the other planes mentioned.

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The answer depends on the strength of the EMP at the aircraft location. This obviously depends on the distance from origin and strength at source.

Aircraft do have some immunity from EMP, they don't just fall from the sky if you make sparks with a 12V car battery 35,000 feet below them.

Here's an extract from Report of the Commission to Assess the Threat to the United States from Electromagnetic Pulse (EMP) Attack.

enter image description here

enter image description here EMP simulator HAGII-C testing a Boeing E-4 aircraft. (Wikipedia)

I've read that many modern FBW aircraft (including Airbus and Boeing) still have some fallback manual control of basic flight controls.

However if all your navigation and communication systems are fried and ATC is completely dead, your chances of gliding to an essentially uncontrolled nearby airfield and making a good landing must be quite small. Especially at night, in the rain, with a new moon.

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Having been in the Air Force and worked on bombers and fighters that can carry nuclear weapons all systems avionics and electronics are shielded from EMP. They are not “one time use” and we want them to return. We have divert bases that some may make it to for refuel and rearming Tierra Del Feugo is one such place. Away from strategic baes in the northern hemisphere. B-52s have been shielded and actually have a lead lined curtain that the pilots pull across the inside of the forward facing cockpit glass. Special grounding on the electrical systems for electronics and avionics direct the electrical pulse away from equipment and mechincal devises that have sensors. Normal passenger aircraft do not receive such attention to detail and any communication equipment would be knocked out. However certain types of engines would remain in operation. What would affect our Air Craft the most is the radioactive blast wave if they were static on the Browns. The Enola Gay flew through the EMP and returned to base along with the second camera airplane, though a lot of film on it was ruined. The two aircraft that dropped bombs on Nagasaki also returned to base without incident.

Aircraft that dropped test bombs on Bikini Atoll never had any problems returning to base. We have developed weaponary that can deliver an EMP without a nuclear explosion, but what's in the works now are lasers

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