Stakes in the Sand: Surveying in the Gulf War

In 1990, US forces arrived in the Persian Gulf with a cornucopia of navigation technologies: not just GPS but also LORAN, TACAN, TERCOM (for cruise missiles), and inertial navigation systems which used laser, electrostatic, or mechanical gyroscopes, as well as old-fashioned manual tools like maps and compasses. So why were US surveyors heading off into the Saudi desert?

The surveyors were from the 30th Engineers Battalion (Topographic), which was deployed to provide map production and distribution, surveying, and terrain analysis services to the theatre. The survey platoon’s work was being done on behalf of the Corps and divisional artillery, which had their own particular navigational needs. Unlike fighter or helicopter pilots, field artillery gunners didn’t have the opportunity to see their targets and make last-minute adjustments to their own aim. Unlike bomber crews or cruise missiles, their fire missions were not planned well in advance using specialized materials. To provide precise positioning information to the guns, each artillery battalion in the Gulf was equipped with two Position and Azimuth Determining Systems (PADS), truck-mounted inertial navigation systems that keep an ongoing track of the unit’s positions. At the heart of the PADS was the standard US Navy inertial navigation system, the AN/ASN-92 Carrier Inertial Navigation System (CAINS).

Like all inertial navigation systems, PADS had a tendency to drift over time. That meant that it required regular refreshes using a pre-surveyed location, or control point. The initial specifications for PADS were to achieve a horizontal position accuracy of 20 meters over 6 hours and 220 kilometers. Actual horizontal accuracy seems to have been far better, more like 5 meters. One reason for the high accuracy was that, unlike an airplane, the vehicle carrying the PADS could come to a complete stop, during which the system detect and compensate for some of the errors by the accelerometers in the horizontal plane.

Unfortunately, the US had exactly one control point in Saudi Arabia, at Dharan airbase (Army Reserve historian John Brinkerhoff says this and several other point surveyed were done with “Doppler based methods.” I assume that means using the TRANSIT satellite system, which determined location on the basis of Doppler shift). Starting from that control point, the 30th’s surveyors extended a network of new control points northwards and westwards towards the Iraqi border. Conventional line-of-sight survey methods would have been too slow, but the surveyors had received four GPS receivers in 1989 and soon got more from the Engineer Topographic Laboratories to equip a follow-up team of surveyors. Eventually, their survey covered 10,000 square kilometers and included 95 control points. Relative GPS positioning took about two hours (according to Brinkerhoff) and offered accuracy to about 10 centimerers (compared to 17 meters for regular GPS use). Absolute positioning – done more rarely – required four hours of data collection and provided accuracy of 1–5 meters.

When the ground war began on 24 February 1991, the two survey teams tried to stay ahead of the artillery, which meant driving unescorted into the desert and marking new control points with steel pickets with reflectors (for daytime) and blinking lights (for night-time). Providing location data through headquarters was too slow, so the surveyors took to handing it directly to the artillery’s own surveyors or just tacking it to the pickets. By the ceasefire on March 1 they had surveyed all the way to 30 km west of Basra. Where the artillery outran the control points they used their own GPS receivers to make a “good enough” control point and reinitialized the battalion PADS there, so all the artillery batteries would at least share a common datum. One thing PADS could do and GPS couldn’t was provide directional information (azimuth), so units that outran their PADS capabilities had to use celestial observations or magnetic compasses to determine direction.

What the 30th Battalion and the artillery’s surveyors did in the Gulf was different enough from traditional survey methods that the some in the army already used a different phrase, “point positioning,” to describe it. In the 1968–1978 history for the Engineer Topographic Laboratories, which designed army surveying equipment, PADS was one of three surveying and land navigation instruments singled out as part of this new paradigm (the others were a a light gyroscope theodolite with the acronym SIAGL and the Analytical Photogrammetric Positioning System).

Brinkerhoff tells the story of the 30th’s surveyors as the meeting of the high and low tech, but the work really relied on a whole range of technology. Most of the GPS surveying was relative positioning that was anchored to previous Doppler surveying. Position and azimuth information was carried forward by inertial navigation, and the position of the firing battery was paired with target information from a forward observer equipped with GPS, an inertial navigation system, or a paper map or from aerial photography which could be interpreted using the aeroplane’s own navigation system or a photointerpreter’s tool like APPS. GPS surveying and navigation did not stay wrapped up with all these other navigational tools for long. The technology was flexible enough to be used in place of many of them. But in the early 1990s, GPS’s success was contingent on these other systems too.

Sources Notes: The story of the 30th and its surveyors appears in John Brinkerhoff’s monograph United States Army Reserve in Operation Desert Storm. Engineer Support at Echelons Above Corps: The 416th Engineer Command (printed in 1992). Further details appear in the Army Corps of Engineers history Supporting the Troops: The U.S. Army Corps of Engineers in the Persian Gulf War (1996) by Janet A. McDonnell and “The Topographic Challenge of DESERT SHIELD and DESERT STORM” by Edward J. Wright in the March 1992 issue of Military Review. Reflections on how the artillery used PADS and GPS in the Gulf come from the October 1991 issue of Field Artillery, a special issue on “Redlegs in the Gulf.” Technical details for PADS are from the ETL History Update, 1968–1978 by Edward C. Ezell (1979).

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A Curious Path for Guidance Technology: MEMS and the Military

At the end of my blog post about laser gryoscopes, I mentioned that pretty much every smartphone now has microelectromechanical (MEMS) gryoscopes or accelerometers inside its case, and that too was development funded by the US Department of Defense. It was pretty much a throwaway observation about I which knew nothing more, so it was very neat to see a whole chapter on government funding for MEMS in a new book from NASA, Historical Studies in the Societal Impact of Spaceflight.

As the chapter’s author, Andrew J. Butrica, explains, a lot of the early research into MEMS was done at and around Stanford University and its Integrated Circuits Laboratory in the 70s. One of the lab’s partners and funders was NASA’s Ames Research Center, whose interest was mainly in the opportunities to use MEMS instruments in biomedical research. Another was the National Institutes of Health, also interested in medical research, which put more than a million dollars a year into the Integrated Circuits lab. A third, and one who had been funding electronics research at Stanford since the 1940s, was the military’s Joint Services Electronics Program. The first MEMS accelerometer, described in a 1977 dissertation by Stanford electrical engineering student Lynn Michael Roylance, was funded for its first two years of development by the Joint Services Electronics Program and in part thereafter by a NASA grant.

What happened next would have seemed really weird if I didn’t already know about the winding path towards military use that the laser gyroscope took. One of the earliest widespread adopters of MEMS sensors was the automotive industry, which used MEMS pressure sensors to measure the air pressure in engine manifolds, MEMS accelerometers to trigger airbags in case of sudden deceleration, and MEMS gyroscopes to guide anti-skid and rollover detection systems. Automobile manufacturers liked MEMS sensors for their small size and reliability, which also made them good for use in guided munitions. Starting in 1990 or so, when the global market for MEMS devices had grown to $480 million (according to the March 1, 1993 issue of Aviation Week and Space Technology), development came full circle and MEMS sensors started turning up in weapons. A quartz tuning fork gyro was integrated into the Maverick anti-tank missile in 1990, while in 1995–6 automotive-grade MEMS components were used to build a prototype guided shell, the Extended-Range Guided Munition (ERGM), for the US Navy.

Interestingly, the sensors in the ERGM were built by Draper Labs, better known for designing extremely precise gryos and accelerometers for use in intercontinental ballistic missiles, who had used an initial government-funded investment in MEMS development to enter the automotive MEMS sensor market. (There’s a lot of good information on those developments, much of it written by Draper Labs staff, in this NATO paper collection.)

Obviously, the use of MEMS in cars and commercial electronics (like the Nintendo Wii and Apple iPhone) were not the only factor in continuing development. From 1992 on, the Defense Advanced Research Projects Agency (DARPA) invested in MEMS research through its Microsystems Technology Office. So did national labs like Sandia, and presumably many others – I’m sure I still only know a small slice of what was going on with MEMS in these years. Still, it’s interesting to see another case of what still strikes me as surprising – development coming full circle from speculative military research through commercialization to practical military use.

The Other Lasers of the Gulf War, Part Three

Part of a three-part series on the development of the laser gyroscope and its military use. Back to Part Two or Part One

Meaning and Legacy
Sociologist Donald MacKenzie, whose book Inventing Accuracy remains pretty much the classic history of inertial guidance development, convincingly argues that there was nothing inevitable about the choices made in the development of these inertial navigation systems. After all, despite widespread military adoption in the mid-1980s, the laser gyro was hardly the only game in town. Despite granting $135 million in development funds to design laser gyro guidance systems for the abortive Small ICBM (aka the “Midgetman”) the US Air Force decided that the laser gyro wouldn’t meet the requirements and borrowed the mechanical gyro system used in the MX ballistic missile instead. Likewise, the F-117 stealth fighter entered service with the precise but off-the-shelf SPD/GEANS INS. Instead, the decisions to fund, buy, and develop technologies like the laser gyro reflected the strategic plans, aspirations, and expectations of technologists and users, as well as sheer coincidence. Charles Stark Draper was right that mechanical gryos would continue to be and to become more accurate for the foreseeable future, but the laser gyro had the promise of a radical technological breakthrough and the sexiness of the very word laser.

The case of the laser gyro also shows how tough it is to pigeonhole a technology as “military” or “civilian” in its origins. Is the laser gyro military technology because much of the initial development money came from military sources? Is it civilian technology because it was the commercial airliner industry that first bought them en masse and made the transition from prototype to standardized product? Does tracing that history help us understand how precision navigation contributes to either sphere of action?

I started looking at the navigational tools applied during the first Gulf War because of Ingrid Burrington’s article on a 1990s protest against GPS because of its military origins (which I commented on here). Writing in the Atlantic, Burrington describes how activists Keith Kjoller and Peter Lumsdaine snuck into a Rockwell International facility in Seal Beach, California and used wood-splitting axes to smash up nine GPS satellites “to slow the deployment of this system (which) makes conventional warfare much more lethal and nuclear war winnable in the eyes of some.”

Interviewed by Burrington twenty-two years later, Lumsdaine was firm that GPS remains “military in its origins, military in its goals, military in its development.” What I wanted to investigate was what that meant in comparison to all the other systems that contributed to the type of aerial campaign launched in the Gulf. Along the way examples dropped into my lap of similar protests against those technologies. Mass opposition to the installation of transmission towers for the Omega radionavigation aid, as opposed to the more precise and more military-used Loran-C. The bombing of a factory for the inertial navigation systems of the Air-Launched Cruise Missile.

Trying to parse the role of the laser gyroscope in the first Gulf War is tough because it was so widespread. I can’t find anyone who writes about using an INS in the Gulf, perhaps because it was such a mundane occurrence. But the development path of the laser gyro shows that calling it a military technology involves making some presumptions about whose contributions mattered. Early inertial navigation was bought and paid for by the military because of its use in strategic (i.e. nuclear) weapons, but within twenty years had trickled down into commercial aviation. The laser gyro was similarly funded in its development by the armed forces, but they went on to shun it as an initial product because it was not yet superior to what they had in service. It was commercial aviation, the previous trickle-down beneficiary, who put up the funds to turn the laser gyroscope into a practical and widespread device. This was technology that was normalized as civilian before it was normal in the military.

Perhaps not coincidentally, alongside the GPS receiver you probably carry in your pocket you also have a set of accelerometers and gyroscopes. Most modern smartphones include microelectromechanical (MEMS) inertial sensors to measure orientation and motion, which is used to do things like change the screen orientation when you turn your phone sideways. (This is a very cool video that explains how a MEMS accelerometer works and how it is manufactured.) Should you be concerned that you’re carrying around a miniaturized, albeit inaccurate, version of the technology mounted on the first ICBMs? Quite possibly, considering that researchers have shown how the gyroscopes in a phone could be used to eavesdrop on nearby audio or keystrokes. But probably not because it was the US Department of Defense that funded its origins.

Source Notes: Not much has been written about the history of gyroscope development. The notable exception is Donald MacKenzie’s exceptional history Inventing Accuracy: A Historical Sociology of Nuclear Missile Guidance. MacKenzie’s history of the laser gyroscope is a separate article, “From the Luminiferous Ether to the Boeing 757: A History of the Laser Gyroscope” (Technology and Culture, July 1993). Paul G. Savage’s paper “Blazing Gyros – The Evolution of Strapdown Inertial Navigation Technology for Aircraft” (originally published in Journal of Guidance, Control, and Dynamics, May/June 2013) was also very useful. Given the absence of broader histories, Flight magazine’s archive was very useful for filling in some details.

The Other Lasers of the Gulf War, Part One

Of the many weapons guidance systems used during the Gulf War, the one with by far the most impact must have been the laser. Though the first laser-guided bombs had been used during the later years of the Vietnam War, it was in the Gulf that they became gold standard for precision guided bombing. Nor was laser guidance only for ordnance dropped from aircraft. US Army attack helicopters used the laser-guide Hellfire missile and US Army artillery fired Copperhead laser-guided artillery shells, although the latter was so expensive that only ninety were used during the entire war.

As important as the laser was to all these precision guided weapons, though, it also had a far more precise and hidden use during the Gulf War. Almost every warplane that flew during the Gulf War was equipped with an inertial navigation system (INS). A precise guide to that airplane’s location even in the absence of navigational signals like GPS, the INS was an essential navigational tool for wartime aviators.

The basic components of each INS are more or less the same: a set of gyroscopes to measure the rotation (and thus the direction) of the vehicle, a set of accelerometers to measure the vehicle’s acceleration, and a computer to integrate the information. In the planes flying in 1991, those gyroscopes were built around a miniature laser. The eerie glow coming from an exposed ring laser gyroscope looks like something from a science fiction movie – military technology blog Foxtrot Alpha says “it looks like something Doc Brown would be working on in his garage.” However, if it hadn’t been for a few lucky breaks and the demands of tens of thousands of economy-class passengers the laser gyro might never have ended up as more than a technological novelty.

The Path to the Laser Gyro
Though the gyroscope was a far older invention, the combination of components that made up an inertial navigation system came together towards the end of the Second World War in the guidance system for the V-2 rocket. They arrived in America after the war, developed by several groups but particularly by Charles Stark Draper and the MIT Instrumentation Laboratory. Inertial navigation systems “drift” as small errors in the measurements by the gyroscopes and accelerometers accumulate and Draper was single-minded in his quest to reduce those errors through advanced design and precision engineering.

The first INSs were expensive and relatively inaccurate but became a vital component of strategic weapons systems, including the first intercontinental ballistic missiles (ICBMs). However, by the early 1960s moderate-cost inertial navigation systems that drifted at rates of only 0.8–1 nautical mile per hour became available for use in military aircraft. Three companies built the majority of them in the United States: Kearfott, Litton Industries (who would later built the INS used in the Air-Launched Cruise Missile and have their Toronto factory bombed as a result), and AC Spark Plug (later AC Delco). A fourth, Honeywell, built high accuracy systems for classified projects such as the SR-71 but failed to seize a substantial share of the wider marked because the technology involved was too classified to be used outside those top secret programs.

The moderate-cost, moderate-accuracy INS quickly spread from the defense sector into the commercial airline market. Early tests by Litton and by Sperry Gyroscope, one of the early gyroscope manufacturers, were followed in 1967 by Boeing’s announcement that AC Delco’s Carousel IV INS had beat out offerings by Kearfott, Litton, and Sperry, as well as Nortronics, to be a standard option on their new jumbo jet, the 747. The following year, American Airlines retrofitted twenty-nine Boeing 707s with INSs built by Litton Industries that had a drift rate of 1.5 nautical miles per hour.

Both expert gyro-builders like Draper and clients like the US Air Force expected the precision of new INSs to grow. The problem was that it wasn’t clear whether that accuracy was either needed or worth the price. Honeywell did successfully sell the Air Force a high-precision INS, accurate to a tenth of a nautical mile per hour, but the Standard Precision Navigator/Gimballed Electrostatic Aircraft Navigation System (SPN/GEANS) only ended up being installed on the upgraded B-52G. As John Bailey told Donald MacKenzie that “we did an awful lot of marketing work on the Strategic Air Command to try to convince them of the advantages of a tenth of a mile per hour system,” and it still took four years and an end-run around standard acquisition procedures to get SPN/GEANS adopted.

As an alternative, INS developers were exploring the idea of a “strapdown” INS, which would abandon the gimballed platform that kept the INS from experiencing the pitch and roll of its platform and instead use the computer to isolate the airplane’s movement through space from its many motions. By omitting the gimballed platform, a strapdown INS would have far fewer moving parts and offer better reliability. Conventional gyros were ill-suited to the demands of strapdown operation so INS developers looked for new gyroscope designs to use instead. The leading contender was the electrostatically suspended gyro (ESG). Unlike traditional gyroscopes that spun a circular rotor on bearings either in gas or fluid, the ESG spun a spherical ball suspended in a vacuum by an electrostatic field. Honeywell, their leading builder, called it “the world’s most perfect gyro.” The Honeywell SPN/GEANS used ESGs to deliver its superior performance, but the technology was also applicable to less precise strapdown applications. Rockwell Autonetics, for example, used the ESG as in their strapdown military INS, the MICRO Navigator (MICRON). By 1974, MICRON was entering the advanced stages of development and the Air Force had budgeted $25 million for full-scale production development.

There was, however, a dark horse in the running to become the heart of the next generation of inertial navigation systems: a “gyro” operating on entirely different physical principles and built around a technology that was itself less than fifteen years old.

To Part Two: Enter the Laser

The Pathfinders of Task Force Normandy

Though the F-117 stealth bomber, the Tomahawk cruise missile, and the laser-guided bomb probably garnered the majority of the public attention and accolades during the first Gulf War air campaign, true aficionados know first shots fired in the war came not from any type of Air Force jet but from two quarters of Army attack helicopters in the Iraqi desert. Their attack on two early warning radar stations, code-named EAGER ANVIL, is yet another example of the apparent transformation that GPS enabled. Led by Air Force special operation helicopters, the joint team known as Task Force Normandy flew more than twenty miles into Iraq, across mostly featureless desert on a moonless night to destroy two radars and open up a gap in the Iraqi air defense network for the Coalition’s air forces to exploit.

The mission’s origins were somewhat convoluted. What began as a planned ground assault by Army special forces infiltrated over the border on foot gradually morphed into a joint helicopter attack by Air Force special operations helicopters and AH-64 Apache attack helicopters from the Army’s 101st Airborne Division. The mission couldn’t be handed over to the Apaches alone because AH-64’s Doppler radar navigation system was, as one aviation officer put it, only “a ball park navigator” that would drift 300–500 meters in a two-hour flight (GAO/OSI-93-4, p.55).

MH-53J Pave Low IIIE. MSgt Dave Nolan, Airman Magazine

MH-53J Pave Low IIIE. Photo by MSgt Dave Nolan, Airman Magazine.

The Air Force’s MH-53J Pave Low III helicopters, on the other hand, had one of the most impressive navigational packages in the US military. What had began as a series of improvements to the Air Force’s combat search and rescue (CSAR) helicopters during the Vietnam War had in the subsequent twenty years become the Air Force’s premier rotary special operations capability. When the Pave Low III went into service in 1979, it had a precision navigation system that included terrain following/terrain avoidance radar, a forward-looking infrared (FLIR) sensor, and a combination Doppler radar and inertial navigation system connected to a projected “moving map” display. The upgrade to the Pave Low III Enhanced configuration in the late 1980s gave the Pave Low community some of the first GPS receivers in the military. Major Ed Reed, one of the program managers, recalled that:

“I went to the first GPS meeting. I was a junior major there and everybody listed all of the aircraft that were going to get GPS and . . . every fighter was covered, every bomber was covered. And then some line in the nineties, the H-53 was going to get it. Wrong answer! I said, ‘Sorry, I’ve got a FAD-1 so I move to the front of the line.’ They said, ‘You can’t do that. We’ve got this list!’ I said, “You’d better call this office and find out if that’s going to be your list at the end of the day. So later I got a nice phone call. They said, ‘You can have the first boxes off the line.’ I said, ‘That would work just fine.’” (On A Steel Horse I Ride, p.229)

Because of this, Task Force Normandy paired four Pave Low helicopters with eight Apaches. Ten miles out from the targets, crew on board the Pave Lows would drop clusters of chemical lights. The Apaches would update their Doppler navigation systems as they flew over the lights, then close in their targets and destroy them with laser-guided Hellfire missiles, rockets, and gunfire.

Despite its challenging nature and the uncertainty surrounding it, the mission went smoothly. After four minutes, twenty-seven Hellfire missiles, 100 rockets and 4,000 rounds of 30mm ammunition, both radar sites were destroyed. No aircraft were lost.

Task Force Normandy’s mission is a great encapsulation of both the contribution GPS made to the Gulf War and the limits of that contribution. GPS made navigation on the mission more or less trivial (though I’m not sure it would have been impossible with the pre-GPS Pave Low navigation computer), but the capability was tied to those helicopters rather than a broader network. To pass navigational information to the accompanying Apache’s, Task Force Normandy had to resort to a supremely low-tech solution.

The problem was that while GPS was global, it was not universal. A GPS receiver knew its location to within ten meters, but that knowledge only had meaning in conjunction with other, less precise information – like maps or the navigational systems on other aircraft. The problem was particularly apparent for search and rescue, the primary mission for the Air Force special operations force. As Lieutenant Colonel Richard Comer, the commander of the squadron which flew the Pave Low in Desert Storm, described it:

We were dealing with coordinates from somebody who was flying out there and doing acrobatics dodging missiles with an INS or Doppler, [which is why] his coordinate wasn’t going to be close to where that person was on our GPS. We didn’t know that. We thought that . . . we should just be able to fly to it and be able to hover above the guy and be able to drop the hoist down through the fog and pick him up. We didn’t know. (CSAR in Desert Storm, p.153)

Even small differences in the systems of coordinates GPS used could make the difference. B-52 bombers that initialized their inertial navigation systems at Diego Garcia using coordinates from WGS72 datum dropped their bombs 400–600 feet away from targets whose coordinates were set using the WGS84 datum. The full value of global positioning, it appeared, only appeared when friend and foes had commensurable a global position.

TERCOM, System and Symbol: Part Three

From Part Two

Direct Action’s bombing of the Litton factory in Rexdale and its assembly line for cruise missile guidance systems reflected discomfort on the Canadian left with the way the Cold War was heating up again after the years of détente and what they saw as an insufficient willingness to put distance between Canada and US foreign policy. Neither it, nor the anti-cruise missile protests, put much specific emphasis on the technology involved. For them, TERCOM itself was just one particular articulation of the US military-industrial complex.

In fact, TERCOM in general was a dead end in military guidance. No other weapons used the same guidance technique, and both the Tomahawk and conventional ALCM used GPS as their primary guidance as soon as practical. I have yet to see any reference to a commercial spin-off from TERCOM either. The idea was more or less a one-off as a guidance technique. It survived into the twenty-first century in only one niche, the nuclear-armed Tomahawk. Because, unlike GPS or other radionavigation systems, there were no outside signals to be jammed or spoofed, TERCOM-assisted inertial navigation remained the sole guidance system on the nuclear-armed Tomahawks even after the conventional versions switched over using to GPS. The last nuclear-armed Tomahawks were only retired in 2013.

On the other hand, TERCOM did demonstrate the value and cost of good mapping, charting and geodetic data. It wasn’t the first system to make use of it – every US strategic bomber and ballistic missile relied on mapping and geodetic information to some extent – but it was the first to demand not just knowledge about Point A and Point B but also about the terrain along the way. That requirement put the Defense Mapping Agency in a bind, forcing it both to go into overdrive and to triage its TERCOM processing work. Recognising that that sort of crash project couldn’t be repeated for every new weapon, the deputy Secretary of Defense issued Program Decision Memorandum 85 (PDM-85) in 1985, which required early military department to “fund with its own resources the cost of unique earth data products.” Though Larson and Pelletiere wrote in the late 1980s that the rule was proving unenforceable, it was a mark of further recognition that this type of information was a critical war weapon.

After the Cold War ended, the Defense Mapping Agency was merged with many of the intelligence community’s imagery creation and analysis office to create the National Imagery and Mapping Agency (NIMA). In 2003, NIMA was renamed the National Geospatial-Intelligence Agency (NGA), a change that reflected the increasing conceptual consolidation of these kinds of information under the umbrella of geospatial intelligence (GEOINT). The term, as the US Geospatial Intelligence Foundation explains, was only about as old as the agency’s new name. But while The Atlantic’s Marc Ambinder could title as story about the agency in 2011 “The Little-Known Agency That Helped Kill Bin Laden,” NGA was pretty deeply embedded in the US national security establishment. More than thirty years after DMA started weaponizing its digital terrain elevation data (DTED), the idea that the military might not only demand detailed maps of its targets but also the underlying data, to transform into a three-dimensional computer model, a physical mockup, or – bringing us right back to the first uses of the DTED – a flight simulator profile (which was, after all, the first use for, back in the 1970s), is old news.

Source Notes: US cruise missiles are pretty widely discussed, so a lot of these posts were cobbled together from a lot of sources. Jay L. Larson and George Pelletiere’s Earth Data and New Weapons (available from DTIC here) was very useful for understanding how the DMA supported TERCOM, and is one of the few places to mention PDM-85. The explanation of how satellite stereophotogrammetry is done comes mostly from the NRO’s internal history Hexagon Mapping Camera Program and Evolution (as reprinted by the Center for the Study of National Reconnaissance). Information about Canadian protests against cruise missile testing and the Litton bombing in Toronto come from John Clearwater’s 2006 book Just Dummies: Cruise Missile Testing in Canada. Ann Hansen, one of Direct Action’s members, published a memoir after he release from prison. Direct Action: Memoirs of an Urban Guerilla offers more but similar details about the Litton bombing and reprints Direct Action’s communique.

TERCOM, System and Symbol: Part Two

Back to Part One

GPS was only one among many guidance technologies that saw their first use in the first Gulf War. One of the others was Terrain Contour Matching (TERCOM), the guidance system behind a trio of American cruise missiles: the sea-launched Tomahawk, Air-Launched Cruise Missile, and ground-launched Gryphon. As Ingrid Burrington reported for the Atlantic earlier this year, GPS provoked some strong feelings that included an axe-wielding attack by peace protesters. TERCOM attracted some of the same attention.

None of the three cruise missile systems were uncontroversial, though the Gryphon attracted the lion’s share of the protests in the European countries where it was to be based (just google “Euromissiles crisis” or “Greenham Common” for a sample). In Canada, US flying tests of the ALCM over northern Alberta as a proxy for the terrain of Siberia led to substantial public protests. Some went beyond vigils, marches, and speeches. Two Greenpeace members climbed the Peace Tower on Parliament Hill in Ottawa to unfurl a banner saying “No cruise, Greenpeace.” An art student, Peter Grayson, threw red ink on a copy of the Canadian constitution on display at the National Archives. In Prince George, BC, an ALCM was burned in effigy, near Wandering River, Alberta, Greenpeace launched a net carried by balloons during one test as a “cruise catcher.”

Canadian involvement with cruise missile development was also the spark for an act of violent protest reminiscent of the Kjoller-Lumsdaine “Harriet Tubman-Sarah Connor Brigade” attack on GPS.

Direct Action in Rexdale
One of the companies building guidance packages for cruise missiles was Litton Systems Canada, the local subsidiary of Litton Industries. On the night of October 14, 1982, the Etobicoke Police Department received a telephone call reporting that there was a blue van filled with explosives parked outside the Litton Systems factory in Rexdale, Toronto. The van, which was filled with 250 kg of dynamite stolen from the British Columbia Highways Ministry earlier that year, was the work of Direct Action, a radical British Columbia group who had already blown up four power transformers on Vancouver Island to protest BC Hydro’s development there. Three of what became known as the “Squamish Five” after their arrest – Brent Taylor, Juliet Belmas, and Ann Brit Hansen – drove out to Toronto to carry out the bombing.

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Their target, Litton Industries’ Plant no. 402, had already been the site of protests against Litton’s cruise missile production contract. Direct Action took pains to avoid any casualties from their bombing. They placed an orange box with two sticks of dynamite and a warning on the van’s hood, then phoned in a warning message to the police. Despite their precautions, the bomb in the van detonated early, putting nine people in hospital. In their post-bombing communiqué, the group apologized for the injuries before going on to condemn Canadian complicity in the nuclear arms race.

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Direct Action’s members soon moved on to other activities, firebombing a series of stories in the Red Hot Video pornography chain and planning the robbery of a Brinks armored car, before they were captured by the RCMP in early 1983. Their attack on the Litton factory had effectively no effect on the work done there. John Clearwater, whose book on the subject documents the eighteen flight tests and the related protests in painstaking detail, reports:

the explosion did not stop cruise missile navigation systems production. In fact, the area in the factory, well insulated from shock and vibration, remained unharmed. The test pedestals on which the delicate instruments were calibrated remained mounted on their steel and concrete columns sunk far into the soil beneath the factory. After the blast, technicians simply rechecked the alignment of the test-beds with the stars and the earth’s axis to ensure the perfection of the TERCOM navigation instruments. Production was not halted. (Just Dummies, page 102.)

Hansen’s own memoir reported that the factory’s work was disrupted for only two days.

Direct Action’s communiqué taking responsibility for the Litton Systems bombing rooted their opposition to the cruise missile in opposition to nuclear war, as “the ultimate expression of the negative characteristics of Western Civilization,” whose “roots lie deep in centuries of patriarchy, racism, imperialism, class domination, and all others forms of violence and oppression that have scarred human history.” They condemned the cruise missile as one of set of weapons “designed for offensive first-strike use” (including the Pershing II, Trident, and neutron bomb), as well as Canadian involvement in US nuclear weapons production: not just Litton’s work on the cruise missile, but also launchers for Lance missiles by Hawker-Siddeley, hull cylinder torpedo tubes for Polaris, Poseidon, and Trident by Vickers, cranes to load Trident missiles by Heeds Inernational, and one component of the MX missile. In the context of Direct Action’s critique, neither inertial navigation nor terrain contour matching was of much specific interest.

Forward to Part Three