Electromegnetic Pulse: The Continuing Threat To Our Command And Control Systems

AUTHOR Major Larry D. Hosler, USMC

CSC 1989

SUBJECT AREA - C4

EXECUTIVE SUMMARY

TITLE: ELECTROMAGNETIC PULSE: THE CONTINUING THREAT TO OUR

COMMAND AND CONTROL SYSTEMS

THESIS: The widespread use of the integrated circuit, such as

those used in computers and most other modern electronic

devices, has increased the possibility of severe degradation

or possible total destruction of our command and control

networks by the phenomenon known as Electromagnetic Pulse

(EMP).

ISSUE: The miniaturization of computer systems and other

electronic control devices, made possible by the use of inte-

grated circuits, has allowed for their use in places where it

has previously been impossible. They are now commonly found

in all communications systems as well as satellites, missiles,

airplanes, etc. Unfortunately, the design of the integrated

circuit makes it very suspectable to being destroyed or

disabled by the induction of a sharp increase in voltage such

as that caused by EMP. The phenomenon of EMP is one resultant

of an atmospheric nuclear detonation which can cause an

emission of electrons with a peak of up to 50,000 volts per

meter. For example, a detonation at an altitude of 200 miles

above the central United States would bathe the entire United

States and parts of Canada and Mexico in EMP. This would

essentially shut down all unprotected electronic devices. A

tremendous threat to our national security is posed by the

vulnerability of our Defense Command and Control system to

EMP. This system, which consists of a world wide communica-

tions network of telephones, command posts, special circuits,

and satellites designed to link both military and civilian

leaders, is a notable target. In the last several years, many

of our systems have been hardened in some manner to reduce

that vulnerability. The problem is, we have only scratched

the surface and protecting all of our systems may not feasible

for years to come, if at all.

CONCLUSION: Future efforts should be directed toward

designing new command and control equipment that is properly

protected and in improving our capability in validating system-

level EMP vulnerability. Each new item of equipment in the

command and control spectrum procured by the Department of

Defense should be analyzed more for its survivability than for

just its cost.

ELECTROMAGNETIC PULSE: THE CONTINUING THREAT TO OUR COMMAND

AND CONTROL SYSTEMS

OUTLINE

THESIS STATEMENT. The widespread use of the integrated

circuit has increased the possibility of severe degradation or

possible destruction of our command and control networks by

the phenomenon known as Electromagnetic Pulse (EMP).

I. The introduction of high-tech into our command and

control systems

A. Development of the Computer

1. The Electronic Numerical Integrator and Computer

(ENIAC)

2. Vacuum Tubes to the Integrated Circuits

B. Computers and the Military

II. Electromagnetic Pulse

A. Definition

B. Causes and Effects

1. Functional Damage

2. Operational Upset

C. Trinity Nuclear Test at Alamogorado, New Mexico,

1945

D. Fishbowl Test Series, 1962

III. Proposed Corrective Measures

A. Increased use of Satellites

B. System Shielding

C. Filter Networks

D. Fiber-Optic Circuitry

E. High-Speed Zener Diode

IV. EMP and the Soviets

V. Future Innovations

A. Improve Testing Capability

B. Develop Methods for Validating EMP Hardness

C. Design of New Systems

ELECTROMAGNETIC PULSE: THE CONTINUING THREAT TO OUR COMMAND

AND CONTROL SYSTEMS

The completion of the world's first fully operational

electronic computer, the Electronic Numerical Integrator and

Computer (ENIAC) by John Mauchly in 19491 has opened up an

avenue of technology which has progressed at a rapid pace. In

a period of a mere forty years computers have changed

tremendously in size, internal makeup, computing time, and

memory. ENIAC occupied 15,000 square feet, contained 19,000

vacuum tubes, had little internal storage capacity, and was

programmed by plugging and unplugging some 6,000 switches

which covered three walls. In fact, the first computer used

commercially was a variation of the ENIAC, called the Univac

I, and was installed by the U.S. Census Bureau. 2

During the late 1950's, the cumbersome vacuum tube was re-

placed by the transistor which drastically reduced the size of

the computer. For example, by using transistors in place of

vacuum tubes, ENIAC would have been reduced from house size to

something like that of a small room. Today as technology con-

tinues to progress, large scale integration (entire circuitry

held on a semiconductor chip) has enabled first hundreds, then

thousands, and now millions of individual units of information

to be compiled on one slice of semiconductor.3

Computers are now able to process data at a tremendous

pace, have increase memory capability, and are yet a fraction

of the size of the original computer. As a result of this

progression, computer technology has been integrated into

every part of our society. However, none seem to utilize the

computer more than the military as the problems they encounter

offer ideal situations for computer use. Defense has also

been the mainstay of research and development in areas such as

interactive computing, networking, data management, graphics,

image processing, natural-language understanding, and speech

understanding.4

Ideally, the military needed something which could analyze

large amounts of data, give accurate results, and make

accurate predictions in a relatively small time frame. Since

the computer was able to perform all these functions, the

military integrated computer technology into every part of its

organization, especially in communications. It is estimated

that the military now spends in excess of 20 billion dollars

per year on this type of technology and that expenditure is

expected to double within the very near future. An example of

the sophistication of the systems utilized by the military is

afforded by the Defense Command, Control, and Communications

System (C3) which consists of a worldwide communications net-

work of telephones, command posts, special circuits, and

satellites designed to link both military and civilian

leaders. Other examples of communications systems that are

heavily dependent on computer support are the Strategic Air

Command (SAC) in Omaha, Nebraska and the North American

Defense System (NORAD) which is located under Cheyenne

Mountain in Colorado.

As stated before, the miniaturization of integrated cir-

cuits has allowed the military to install computer systems for

communication purposes in places where it has previously been

impossible. They are now commonly installed in satellites,

missiles, airplanes, etc. These monumental advancements in

technology, while vastly improving our defense systems, have

in turn created some unique problems to our national security.

The widespread use of the integrated circuit, such as those

used in computers and most other modern electronic devices,

has increased the possibility of severe degradation or poss-

ible total destruction of our command and control networks by

the phenomenon known as electromagnetic pulse (EMP).

EMP is defined as:

"Earth-bound gamma rays from a nuclear explosion

in space eventually hit air in the upper atmos-

phere and knock out Compton electrons, which are

deflected by the earth's magnetic field and

forced to undergo a turning motion about the

field lines. By a complex mechanism, these

electrons emit EMP, which at ground level can

radiate over thousands of miles with a peak

strength of 50,000 volts per meter and can be

picked up by any metal object.5"

By exploding a nuclear warhead 200 miles above the central

United States, the entire United States and parts of Canada

and Mexico would be bathed in EMP which would essentially shut

down the entire power grid throughout the United States, caus-

ing instant pandemonium. All electrical plants would shut

down and telephone lines would go dead, basically shutting

down our entire economy and rendering us helpless and very

vulnerable to enemy attack. The effects of EMP was rather

graphically depicted in the movie The Day After, in which a

simulated nuclear attack deactivated all the automobiles due

to the failure of their electronic ignition or digital control

systems. This occurred even though the additional effects of

the detonation, the shock and thermal wave, were of no

consequence because of the distance from the point of impact.

To put this in a better perspective, consider the fact that

EMP could induce voltage across all electronic circuits to the

level of megavolts whereas the circuits are designed to

operate on but a few volts.

Even if a warhead were detected in time to destroy it, the

destruction itself would cover the United States with EMP.

Needless to say, it would have a tremendous effect on all

electronic systems throughout the United States, including our

defense systems which as previously indicated are heavily

dependent on computers to control the passage of information

throughout its vast network. One defense strategist stated,

it would perform an electromagnetic lobotomy on computer

memories and knock out unprotected communication systems from

coast to coast.6 To bring it down further into the tactical

level, a detonation at an altitude of just 20 miles would more

than cover the area a dispersed carrier battle group would be

operating in. While the ships themselves would survive, the

communications, sensors, and weapons systems would be

disrupted or at least rendered inoperative.7

EMP could effect the system in two ways: (1) functional

damage -- a catastrophic failure that is permanent, such as

burnout of a device or component thus rendering it incapable

of executing its entire range of functions; and (2) operation-

al upset -- temporary impairment such as a change in the state

of switches or flip-flop circuits.8 The amount of damage

would depend to a large extent on the conductor. A conductor

can range from something as obvious as long power and tele-

phone lines to an innocent water line. The defense systems

with it's web of copper cables, microwave towers, switching

centers and command posts would pick up a large amount of

EMP. Equipment does not even have to be connected to the

conductor. Energy from the pulse can be transmitted to the

equipment by electric or magnetic induction or by direct

coupling. Also, EMP can serve as a trigger mechanism by

producing arcing or a change of state, which in turn, allows

the normal operating voltage to cause damage to a piece of

equipment.9 It also seems the more the state-of-the-art the

electronics are, such as with integrated circuits, the more

susceptible they are to EMP damage. In fact, it has been

found that vacuum tubes are 10 million times less susceptible

to EMP than are integrated circuits.10 For susceptibility

of various items to EMP, see Table I.

The military first became aware of EMP in the late 1950's

and early 1960's. The concept was not entirely new, as it had

been predicted as early as 1945 during the Trinity tests at

Alamogordo, New Mexico that a nuclear explosion would generate

some type of electromagnetic field. A more detailed under-

standing of the force and type of electromagnetic field

generated by this type of explosion was discovered during the

Fishbowl series of high-altitude atmospheric tests which were

conducted in the Johnson Islands. Even during these tests,

due to the sophistication of their equipment, the scientists

were able to detect only limited effects. However, in

Honolulu, Hawaii, 800 miles away, the street lights and power

lines broke down and burglar alarms rang throughout the city.

Research attributed these effects to EMP which came from the

high altitude atomic bursts at Johnson Island.11 Further

testing of nuclear weapons at various altitudes was planned in

order to further evaluate the effects of EMP but had to be

stopped after high altitude nuclear testing was banned with

the signing of the Test Ban Treaty.

The threat of EMP to ground-based communication system is

swaying many military personnel in favor of using satellites

for handling long-haul communication. In fact, plans are now

under way to equip the launch control centers of the 1000

Minutemen missiles throughout the United States with satellite

ground stations. Originally these missiles had been built

with four separate channels to the outside world: two by cable

(one for telephone and one for teleprinters), one by high-fre-

quency radio, and one by ultra-high-frequency radio.12 Even

though now there will be five separate ways of commanding the

Minutemen missiles, there is still some doubt of the messages

getting through due to the threat of EMP. Also hooked to the

satellite ground stations are most of the B-52 strategic

bombers as are the airborne command posts. Satellites, though

are not immune to EMP.

There is another type of electromagnetic pulse called

"system generated EMP" (SGEMP) which is emitted from a high

altitude nuclear blast. SGEMP refers to the electric field

that can be generated by the interaction of nuclear (or

ionizing) radiations, particularly gamma rays and x-rays with

various solid materials present in the electronics systems.

Effects include forward-and back-scatter of electrons and

external and internal current generation.13 Basically, the

solid material interacts with gamma and high energy x-rays and

generates an electrical field which can cause damage or

disrupt the on-board electrical systems, thus rendering the

computers controlling communications to an inoperative state.

Also, satellites are even more susceptible if not sufficiently

hardened against EMP. However, in determining the computers

to be installed in satellites, their designers tend to use

more state-of-the-art technology to stay within the specified

weight limitations. Thus, the potential for damage is even

greater than ground based systems in this regard.14 Also,

satellites are very vulnerable to the satellite killers put in

space by the Soviets or the possibility of a direct nuclear

hit. One of our newest satellite systems, the Milstar, will

be a real cut above currently employed satellites. This world-

wide military communications system has not only been hardened

but also designed to be jam-resistant.

As early as the mid 1970's the Department of Defense alone

was spending $250 million per year on EMP testing using simu-

lated nuclear explosions. They were unable to test sufficient-

ly the military communications system due to its extensive

size. However, limited testing on portions of the Autovon

Network by simulated bursts of EMP created a large degree of

damage. Even today with the ongoing tests on all of the vast

defense communications systems, we have no exact idea of how

extensive the damage will be from a nuclear explosion.15

The positive side is that as a result of all the testing

and research done in the area of electromagnetic pulse, there

are potential solutions to the problem. Shielding cables and

systems, wave guides, filters, rearranging circuit layouts,

and increasing grounding techniques are but a few of these

solutions. Unfortunately, for every good point there is a

negative side. Each of these EMP protective devices could add

additional costs to the systems as well as possibly adding

undesired bulk.

Another possible solution is the use of fiber optics.

This is the wave of the future on all systems as it allows for

the placement of larger quantities of communications channels

into a much smaller space than the current copper electrical

wire requires. But the most positive part is that fiber

optics does not pick up EMP and, therefore, does not transmit

the pulses that damage the integrated circuits.16 The nega-

tive side is that the cable must at some point interface with

electronic systems. This means that to insure EMP suppres-

sion, the threat must be eliminated where optical signals are

converted to electronic signals. The addition of Zener diode

switches at this point for example allows for the energy to be

shunted to ground instead of into the equipment. The combina-

tion of fiber optics cable and the Zener diode provide for a

very workable but not all encompassing solution to EMP

protection. At this point, there are numerous methods to

protect a circuit from the energy surge caused by EMP. Each

has its inherent limitations and that, coupled with the

variety of items that must be protected, reinforces the fact

that there is no such item as the perfect protective package.

Another problem that faces the military is the perceived

awareness of EMP by the Soviets. In 1976 a MIG-25 was flown

into Japan by a Soviet defector. At the time, the MIG-25 was

considered to be the world's hottest airplane and is still

today considered to be a very good intercept airplane. During

inspection of the airplane it was discovered that the engine

was of the highest technology; however, the airplane's body

was made of steel instead of titanium and the electronics used

vacuum tubes throughout, but the circuits were far from being

antiquated.17 This led many people to speculate as to

whether the Soviets were more aware of the problems of EMP

than we were and countering the problem by designing their

systems accordingly.

A tremendous threat to our national security is posed by

the vulnerability of our defense systems to EMP. However, we

must make a concerted effort to ensure that increased EMP

protection is an active program throughout the Department of

Defense. It would be inconceivable to think that we could

provide blanket protection for our whole defense command and

control network but certain key areas must be protected and we

can build from there to reduce the threat. An example is the

program instituted in the 60's to protect the Polaris, Minute-

man II and Minuteman III, and Poseidon missiles. As a result

of this testing, standards were established for the survivabil-

ity of strategic systems and is now in use in the protection

of all strategic missiles along with numerous other systems.

Any effort made at protecting the most critical electrical

circuits will achieve a significant reduction in its vulner-

ability to EMP. We fully understand the phenomenon of EMP and

minimum protective standards have been established. The

challenge now lies in promoting the implementation of EMP

protective devices in all future defense command and control

systems. This effort must be accomplished early in the

acquisition cycle. It has been proven over and over again

that any effort at modifying or changing a fielded item of

equipment results in costs that often exceed the original

production model. We certainly can get caught up in the all

to often repeated cycle of obtaining an item of equipment only

because it was the cheapest on the market. The public hue and

cry over the procurement of the B-1 bomber is a prime example.

Many critics had demanded that the Air Force procure

commercial aircraft such as the Boeing 747 as a replacement

for the existing B-52 bomber fleet. On the surface, the

modified Boeing 747 costs half as much as a B-l and could be

configured to carry almost a third (48 versus 30) more air

launched cruise missiles. The major difference and certainly

one of the factors for its overall cost was that the B-1 had

its avionics and electronics systems hardened against the

effects of EMP. As an example, an effort in the 1970's to

harden a Boeing 747 to be used as a flying command post for

the president resulted in a cost increase of five times the

price of a plain commercial model.18 Each new item of equip-

ment in the command and control spectrum procured by the De-

partment of Defense should be analyzed for its survivability,

not just for its cost.

While we understand the phenomenon of EMP and protective

standards have been established, there still exists a require-

ment to validate a systems vulnerability. As previously

stated, we are no longer allowed to conduct atmospheric nu-

clear testing so facilities were established in various parts

of the country for the expressed purpose of exposing equipment

and systems to electromagnetic waves similar to those that

would result from a nuclear blast. These installations are

capable of conducting tests on items as large as the B-1

bomber but uses electronic equipment to generate the waves

vice any nuclear device. Facilities like these are essential

to our required testing but unfortunately, they have come

under the close scrutiny of the environmentalists. As a

result of a suit filed by an organization known as the

Foundation on Economic Trends all of these test facilities

were shutdown in April of 1988. The suit claimed that the EMP

testing was effecting living organisms and could cause cancer.

Environmental studies were conducted and as a result all but

one of the facilities were reopened and testing resumed.19

The most recent setback for continued EMP testing was aired on

the TV series Sixty Minutes on March 5, 1989. During that

show a segment was dedicated to discussing a recently filed

lawsuit by a Boeing employee claiming that he had contracted

Leukemia as a result of working at a Boeing EMP test site.

Preliminary inquiries were inclusive but it was determined

that an above average amount of workers who had similar expos-

ure to this electronically generated EMP as the individual

filing the suit had died from leukemia or like diseases. This

lawsuit will most certainly add fuel to the fire already

started by the environmentalists. Should these test sites be

eliminated as were the high altitude nuclear tests we could be

severely restricted in our efforts to adequately test the

effects of EMP.

As stated previously, a tremendous threat to our national

security and our entire society is posed by the vulnerability

of our command and control systems to EMP. In the last few

years, many of our systems have been hardened in some manner

to reduce their vulnerability. Unfortunately, we have only

scratched the surface and protecting all of our systems may

not be feasible for many years to come, if at all. However,

our future efforts should be directed to designing new systems

that are hardened and improving our capability in system-level

EMP testing. This testing should not only be effective in

validating the EMP hardness of the item tested but shouldn't

compound the problem by causing some environmental catastro-

phe. These efforts at reducing our vulnerability to EMP has

to be done at all levels. It must go from the communicator in

the field and his proper grounding system all the way to the

most critical communications nodes that control our defense

command and control systems. Just by looking throughout the

current command and control systems it can be seen that we are

continuing to make improvements, but have we really done as

much as we should have considering the phenomenon of EMP has

been known about for over twenty-five years.

It is ironic to think that in the case of EMP vulnerabil-

ity, it would appear that state-of-the-art is not always the

best. Maybe those collectors of antique radios and other

electronic devices that used the archaic vacuum tube or owners

of the pre-electronic ignitions cars will have a tremendous

market should there ever be a nuclear incident.

TABLE I

DEGREES OF SUSCEPTIBILITY TO THE EMP

Most Susceptible

Low-power, high-speed digital computer, either transistorized

or vacuum tube (operational upset)

Systems employing transistors of semiconductor rectifiers:

Computers and power supplies

Semiconductor components terminating long cable runs

Alarm systems

Intercom system

Life-support system controls

Some telephone equipment which is partially transistorized

Transistorized receivers and transmitters

Transistorized 60 to 400 cps converters

Transistorized process control systems

Power system controls and communications links

Less Susceptible

Vacuum-tube equipment that does not include semiconductor

rectifiers:

Transmitters Intercom systems

Receivers Teletype-telephone

Alarm systems Power supplies

Equipment employing low-current switches, relays, meters:

Alarms Panel indicators and status

Life-support systems boards

Power system control panels Process controls

Hazardous equipment containing:

Detonators Explosive mixtures

Squibs Rocket fuels

Pyrotechnical devices

Other:

Long power cable runs employing dielectric insulation

Equipment associated with high-energy storage capacitors

Least Susceptible

High-voltage 60 cps equipment

Transformers, motors Rotary converters

Lamps (filament) Heavy-duty relay, circuit

Heaters breakers20

ENDNOTES

1Christopher Evan, The Making of the Micro: A History of

the Computer (Van Nostrand Reinhold Co., New York, 1981),

p. 82.

2Gerald W. Brock, The U.S. Commuter Industry, (Ballinger

Publishing Co., Cambridge, MA, 1975), p. 13.

3Evan, p. 84.

4Michael L. Dertouzos and Joel Moses, The Computer Age: A

Twenty-Year View, (MIT Press, Cambridge, MA, 1979), p. 95.

5William J. Broad, "Nuclear Pulse (I): Awakening to the

Chaos Factor," Science, Vol. 212, (May 29, 1981), p. 1010.

6William J. Broad, "Military Grapples with the Chaos

Factor," Science, Vol. 213, (Sep 11, 1981), p. 1228.

7Lieutenant Commander Richard A. Guida, U.S. Naval Reserve,

"Nuclear Survivability," Proceedings, (Dec 1985), p. 118.

8Samuel Glasstone and Philip J. Dolan, The Effects of

Nuclear Weapons, (United States Departments of Defense and

Energy, 1977), p. 524.

9Glasstone and Dolan, p. 521.

10 Broad, (5/29/81), p. 1010.

11Broad, (5/29/81), p. 1010.

12William J. Broad, "Nuclear Pulse (III): Playing a Wild

Card," Science, Vol. 212, (Jun 12, 1981), p. 1249-1250.

13 Glasstone and Dolan, p. 521.

14Michael King and Paul B. Fleming, "An Overview of the

Effects of Nuclear Weapons on Communications

Capabilities," Signal, (Jan 1980), p. 524.

15William J. Broad, "Nuclear Pulse (II): Ensuring Delivery

of the Doomsday Signal," Science, Vol. 212, (Jun 5, 1981),

p. 1116.

16Broad, (6/5/81), p. 1117.

17Broad, (6/5/81), p. 1012.

18Guida, p. 120.

19"Woodbridge facility dormant pending environmental tests,"

Stafford County Sun Plus, Gary Graig, (Jan 19, 1989), p.1.

20Glassstone and Dolan, p. 525.

BIBLIOGRAPHY

Broad, William J., "Nuclear Pulse (I): Awakening to the Chaos

Factor," Science, 212, (May 29, 1981), p. 1009-12.

Broad, William J., "Nuclear Pulse (II): Ensuring Delivery of

the Doomsday Signal," Science, 212, (Jun 5, 1981), p.

1116-20.

Broad, William J., "Nuclear Pulse (III): Playing a Wild

Card," Science, 212, (Jun 12, 1981), p. 1248-1251.

Broad, William J., "Military Grapples with the Chaos Factor,"

Science, 213, (Sep 11, 1981), p. 1228-29.

Brock, Gerald W., The U.S. Commuter Industry, (Ballinger

Publishing Co., Cambridge, MA, 1975), p. 13.

Connally, Ray, "Military Standard in Jeopardy," Electronics,

55 (Feb 10, 1982), p. 1056.

Dertouzos, Michael L. and Moses, Joel, The Commuter Age: A

Twenty-Year View, (MIT Press, Cambridge, MA, 1979), p. 95.

Evan, Christopher, The Making of the Micro: A History of the

Computer Van Nostrand Reinhold Co., New York, 1981, p. 82.

Fielder, David M., LTC, ARNG, "Protecting Against Electromag-

netic Pulses," Signal, (Apr 1988), p. 45-53.

Fishman, Katherine Davis, The Computer Establishment, Harper

and Row, New York, 1981.

Garbely, Rudy, "Shielding Electronic Components from Nuclear

Effect," Defense Electronics, (May 1987), p. 151-7.

Glasstone, Samuel and Dolan, Philip J., The Effects of Nuclear

Weapons, (United States Departments of Defense and Energy,

1977), p. 514-541.

Guida, Richard A., Lieutenant Commander, U.S. Naval Reserve,

"Nuclear Survivability," Proceedings, (Dec 1985), p.

116-121.

King, Michael and Fleming, Paul B., "An Overview of the

Effects of Nuclear Weapons on Communications Capabili-

ties," Signal, (Jan 1980), p. 59-66.

Soper, Dr. Gordon K. and Casey, Dr. Kendall F., "Understanding

the EMP Threat," Defense Electronics, (Nov 1987), p.

156-169.

Special Report, "Centralized Command systems Being

Modernized," Aviation Week and Space Technology, 116, No.

23, (Jun 7, 1982), p. 80-1.

"Woodbridge facility dormant pending environmental tests,"

Gary Graig, Stafford County Sun Plus, (Jan 19, 1989), p.l.