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High-Altitude Electro Magnetic Pulse
             What is it –
       Where does it come from
• What I am referring to is a nuclear explosion in
  the ionosphere.
• Missile or exploding satellite 200-300 miles up.
• The free electrons in the ionosphere start
  cascading down knocking loose more electrons
  as they collide with air molecules.
• By the time they reach ground level you have
  50,000 – 150,000 volt low amperage power
  surge that will travel along exposed wiring.
                          Solar Flare
•   http://www.space.com/scienceastronomy/mystery_monday_031027.html
     – In early September in 1859, telegraph wires suddenly shorted
       out in the United States and Europe, igniting widespread fires.
     – "The plasma blob that was ejected from the Sun hit the Earth,"
       he said. That's a relatively routine event. What preceded the
       strike was more unusual. "The blob came at exceptionally high
       speeds. It took only 17 hours and 40 minutes to go from the Sun
       to Earth." Solar storms typically take two to four days to traverse
       the 93 million miles (150 million kilometers).
     – the Northern Lights, solar-induced phenomena more closely
       associated with regions near Earth's North Pole, were
       documented as far south as Rome, Havana and Hawaii, with
       similar effects at the South Pole.
     – An electrical storm that causes fires from telegraph wires across
       two continents would do vastly more damage in our electronic
       society of today.
            Asteroid or Comets
• A meteor just missed us by 45,000 miles the last
  week of Feb 2009. That is only twice as far as
  our communications satellites.
  – It was estimated at 20 yards by 30 yards.
  – Roughly the same size leveling nearly 800 square
    miles of forest in the infamous ―Tunguska Event.‖
  – In 1908. something — presumably a meteoroid, most
    experts say — streaked across the sky and exploded
    at an estimated height of 28,000 feet with a force
    equivalent to 185 Hiroshima bombs, leveling some
    800 square miles of forest. Simulations by the Sandia
    National Laboratories showed that object could have
    been just 90 feet across.
  – Large enough to wipe out transistors worldwide.
• February 24th, 2009 a previously unknown
  comet passed within 38 million miles at its
  closest point. =160 times further than the Moon.
                Why do we care?
• Every transistor not protected from surge would blow up.
• Electrical power stations would not function.
• Your car would stall never to restart until you replaced
  the electronic ignition and fuel injection.
• Your unprotected electronics would be toast.
   –   Radios
   –   TVs
   –   Portable phones and cell phones
   –   Modern automobiles.
• The industry to supply new transistors would probably
  also be toast.
• It could take days, weeks, or even months to restore
• If you have a working radio and power after the event it
  could be weeks before you can transmit to anyone.
  How did we find out about HEMP
• In the early 1960’s we successfully shot down some of
  our own Minuteman Missiles with an Anti-Ballistic Missile
  (ABM) with a nuclear warhead.
• It intercepted the Minutemen in the ionosphere
  destroying the missiles while still in space. There was
  no radioactive fallout as the ABM was a ―clean‖ warhead
  and the warheads in the Minutemen were reduced to
  small chunks of plutonium that fell into the ocean.
   – You can handle plutonium if you don’t inhale any powder or have
     open cuts that would allow it into the bloodstream.
   – Your clothing would stop the alpha particles from the plutonium.
   – There are no gamma rays, etc from the chunks.
• In 1859 telegraph was only 3 years old and a solar flare
  caused enough current to cause fires and shorts
  throughout the system.
             Unintended Results
• 800 miles away in Hawaii
   – Cars stalled, but restarted after 10-30 minutes.
   – Street lights and traffic lights came on during the daytime with
     some burning out.
   – Burglar alarms were set off everywhere.
   – The few transistor devices around back then were toast.
   – There was no harm to any humans except for a few traffic
     accidents when the traffic lights all came on at once.
   – All radio and TV channels were jammed for 30 minutes to an
     hour. Some had cooked equipment.
• 3-4 ABMs over the USA would cause nationwide toast.
• We signed the SALT I ABM treaty to ban ABMs because
  the HEMP could do as much damage than letting the
  missiles hit. The US would recover if we lost a few
  cities. What would happen if we lost all communications
  and our vehicles for a year or two?
• My brother’s metal building construction company put
  their computers in a faraday cage to guard against
• Daily they backed up their data and took the tapes to an
  underground lead-lined vault several stories below
  downtown Oklahoma City.
• Military equipment was designed to prevent HEMP
• The F-16 fly (and other aircraft) by wire was tested by
  putting it on a tall wooden ramp and hit by artificial
  lightening. I only know of one ramp.
• Several EMP room size testing facilities still exist to test
  military radios.
• Aircraft like the E-3 AWACS and the flying command
  post are electronically sealed to protect all the electronic
  gear inside and have Xener diodes to prevent EMP from
  coming through cables to antennas, etc.
   – We had to refurbish some of these for AWACS testing because
     they had fallen into disuse when the Berlin wall fell.
 What has changed in peacetime?
• The faraday cage at the metal building company now
  has holes in the walls for local area network wires. The
  wires are not protected. The metal rubber sealed door
  was replaced with a standard door.
• Much of our military equipment is no longer protected.
• I had to fight (with Boeing help) to keep the E-3 AWACS
  protected. Officially we no longer worry about HEMP,
  but with the radar dish and rest of the antenna farm on
  the AWACS, we kept the aircraft protected for the safety
  of the crew from its own emissions.
• Every thing we own is now full of transistors,
• We laughed at the Mig-25 when we discovered it had
  miniature tube type electronics.
   – Tubes are 1 billion times more resistant than to EMP than
How do you protect your equipment?
• Wrap emergency gear in airtight aluminum foil or keep it
  in an airtight metal box until after the HEMP event but
  insulated from the box itself.
• Does your emergency generator have transistor ignition?
• Build your radio shack as a faraday cage by using
  grounded chicken wire in the walls and roof, sealing the
  metal door with rubber gaskets.
• Air exchangers would have grounded metal filters.
• Install Xener diodes on wires.
• Use major surge protectors. We’re not talking a 100 volt
  power surge…a 100,000 volt surge.
• Keep an old hard wired telephone powered from the
  phone line. Hopefully the phone company is still EMP
  protected (last time I visited one was 15 years ago).
• A simple tube type CW rig should still work.
   Iran or another small country
• Ahmadinejad publically stated he wanted to
  attack the US with HEMP.
• Iran may develop a few warheads.
• Iran has Scud missiles with a 600 mile range.
• Iran has modified a freighter to hide, then launch
  a Scud missile.
• He could therefore launch these from outside
  our territorial waters off our coasts and have
  them explode in the ionosphere.
• Many Arab countries have their own satellites
  orbiting around right now. I don’t know if any of
  them contain warheads.
                  Major War?
• I don’t know whether to believe Russia.
  –   They are still doing military R&D
  –   They are still producing military equipment.
  –   Have plenty of warheads.
  –   Sell whatever to unfriendly countries.
• China is still undergoing a major buildup.
  – An old fashioned diesel submarine on battery power
    can be as quiet as a good nuclear sub.
  – Have plenty of warheads.
  – Sell whatever to unfriendly countries.
• Amateur radio may be critical in the future.
• CW will get out when nothing else will.
• If there were no radio or TV stations, a very simple CW
  radio might go far.
• We might consider protecting emergency radios from
• I have no idea what the odds of an EMP event are – I
  have done little on my own.
   – I used to keep a car that would run afterward.
   – I have an receive only emergency radio wrapped in foil inside a
     metal box.
   – I would like to afford a better stored radio.

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