Terrain Analysis, Soviet Style

Yesterday the folks over at Wired posted a really neat article on the Soviet Union’s military mapping program during the Cold War titled Inside the Secret World of Russia’s Cold War Mapmakers.

Russian Map makers

The author seems to imply that the Russians were better at this sort of thing than the US was. Oh pish-posh. I spent most of my 23 year career in the US Army doing this very same thing – compiling what we called terrain intelligence (now called geospatial intelligence) and placing it onto annotated maps or, more commonly, map overlays. This was GIS long before there was GIS.

But while the former Soviets have done a wholesale dump of their formerly classified terrain intelligence data onto the commercial market to make a few bucks, the US and NATO studies are likely still classified and remain under lock and key.

The Soviets and the US (and our NATO partners like the British and Germans) approached the task in the same way – use every available source, from readily available tourist maps to ‘technical intelligence’ (aka, spy satellites) and on-the-ground observers (aka, spies) to compile extremely detailed map-based studies. In my field we tended to concentrate on factors that would directly impact Army ground operations, things like soil conditions, vegetation types, ground slope, road and bridge capacities, building densities in cities and towns, airport and landing zone data, river and stream conditions and much more.

What made the Soviet’s job so much easier is that the West’s open societies gave them virtually unrestricted access to accurate, detailed mapping data compiled for civilian use. A Soviet military attache assigned to their embassy in Washington DC could simply walk out of his embassy compound and stroll a few blocks to one of several well stocked map stores in the US capital. This included, I’m sure, the excellent map holdings over at the National Geographic Society. The US Geological Survey’s map store was just a short drive away in Reston, VA and I’m sure the Soviet Embassy was one of its best customers.

This military attache’s counterpart in the US Embassy in Moscow couldn’t do the same thing. The Soviets simply didn’t sell or give away maps of their territory. Most mapping data, even the most innocuous, was considered classified. That meant we had to get the data some other way. Of course I’m sure we did our share of bribing, cajoling, blackmailing and stealing to get copies of their maps (remember now, this was a cold war; we weren’t playing patty-cake), but we also very quickly developed out ‘technical intelligence’ capabilities – again, spy satellites – that allowed us to accurately map vast areas of the Soviet Union and her client states from space. It is said that the Defense Mapping Agency was the single biggest consumer of spy satellite imagery during the Cold War.

So dear reader, rest assured that while the Soviets were spying on us to develop highly accurate map and geographic intelligence data we were doing the exact same thing to them. We just haven’t seen the need to sell our intelligence on the open market to make a fast buck.

– Brian

Terrain Models

WWII Terrain Model Making

Models.  No, not the gal.  What she’s working on.  This is a shot of a WWII defense worker creating a 3D terrain model based on the aerial photo she’s holding in her hand.

The US Army (and, I suspect, the Marine Corps) loves terrain models, and the use of terrain models for operational and tactical planning, from Army corps all the way down to squad level, has been part of our doctrine since before WWII.

Utah Beach Terrain Model

 US Army officers and NCOs studying a terrain model of Utah Beach before the D-Day landings in June, 1944

A terrain model is nothing more than a 3D representation of a portion of the earth’s surface. For the US military it serves as an adjunct to the topographic map and helps Soldiers better visualize the steps or phases of the operation they are about to execute.

A terrain model can be something as simple as an impromptu sand table scratched out on the desert floor by a squad leader somewhere in Iraq, or a highly accurate, scaled and detail correct product built by modeling experts.

Impromptu sand table

 An impromptu ‘sand table’ set up by a small unit leader to walk his Soldiers through a tactical operation. The white tape represents roads and the boxes and ammo can represent the various buildings. Crude, but effective

One of the best examples of a professionally done military terrain model is the prison camp model code named ‘Barbara’ that was built to support the US Special Operations raid on the Son Tay Prison camp in North Vietnam. The model was built by professional modelers working for the CIA and was based on Corona satellite and SR-71 reconnaissance photos.  Even the heights and crown diameters of the trees in and around the compound were properly scaled so the pilots could evaluate the best areas to set their helicopters down.

SonTay Raid Terrain Model 'Barbara'

 The terrain model code named ‘Barbara’ that was constructed in 1970 to support the planning for Operation Ivory Coast, the raid on the Son Tay prison camp in North Vietnam. The goal was to free American POWs reported to be imprisoned there. While the raid found no prisoners it was considered a success because it was executed without a hitch and so unnerved the North Vietnamese that they instituted better care and prison conditions for all American POWs

And sometimes your ‘allies’ are so lacking in map reading and military operational skills that the only way to get the point across is to walk them through the operation using a terrain model.

3rd Battalion, 3rd Marines terrain model in Afghanistan

3rd Battalion, 3rd Marines in Afghanistan, walking members of the Afghan National Army and Police through the phases of a joint military operation using a terrain model

While the use of sand tables and terrain models is ingrained in how we train our small unit leaders, doctrine addressing just who was responsible for building the more formal and complex terrain models was always lacking. The problem I frequently ran into as a Terrain Analysis Technician (Warrant Officer) in charge of small detachments of enlisted Terrain Analysts was that our commanders frequently associated ‘terrain analysis’ with ‘terrain model’ and assumed that making terrain models was my job. I actually had one Engineer brigade commander lecture me on how he knew with absolute certainty that terrain analysis units were specially trained in making terrain models and that we even had special modeling equipment as part of our equipment authorization. It also didn’t help that we often had talented artists in our terrain analysis units who enjoyed making terrain models and would often sell their services around the command headquarters. (Yes, I’m talking about you, Mark Nielander!)

There was a US Army Forces Command (FORSCOM) regulation that prohibited using Army terrain analysis and topographic units to make terrain models, but that never slowed down eager senior commanders who just couldn’t live without a terrain model. In one memorable episode in the mid-90’s the III Corps Commander at Fort Hood, LTG Tom Schwartz, directed a large scale terrain model of our operational area in Korea be set up inside the headquarters building for an upcoming joint exercise. My boss, the III Corps G2, looked me in the eye and said “get it done”.  I helpfully passed him a copy of the FORSCOM regulation. Without even glancing at it he dropped it into the trash can, looked me in the eye again and said “get it done”. Yes sir, yes sir, three bags full.

Thankfully the Deputy G2 had wrangled a bunch of sharp NCOs from both the G2 and G3 sections to do the actual work, so all I did was advise.  Over the Christmas 1995 holiday season a terrain model of the central Korean peninsula emerged that filled the entire floor of one of the headquarters building atriums (and if you’ve ever been in the III Corps headquarters building you know how big that space is). It was made out of crushed newspaper and spray foam insulation, with hand painted details. The G2 even had little airplane models buzzing overhead on special wires to represent the early UAV systems he had at this disposal. The model was so big that our standard laser pointers didn’t have the power or reach to highlight the key areas. One of our sharp NCOs ran over to the post theater and borrowed a portable theater light with a spot filter. We set the light up on the second floor of the atrium overlooking the terrain model and used that as the ‘pointer’.

By the time model was done it was like a carnival sideshow, with folks from near and far dropping in to marvel at what had to be the most outlandish and cheesy terrain model ever built. General Schwartz loved it.

Today the digital world is awash in ‘terrain visualization’ software. Given the high resolution imagery and elevation datasets available for just about anywhere our military forces fight it is easy to generate realistic and accurate computer models almost on the fly. But still, nothing satisfies like a physical model (just like nothing satisfies like a paper map). That’s why digital-to-solid terrain modeling systems have come on strong in the past several years.  As this picture shows, when you’ve got to gather up a bunch of folks to look at a key piece of terrain nothing fits the bill like a real terrain model.

Fort Irwin Terrain Model

A solid terrain model of Fort Irwin, California, generated from digital data by Solid Terrain Modeling, Inc. The model was first shown at the 2003 ESRI International User Conference in San Diego. Since this show the technology has gotten faster, cheaper and easier to use

So what’s on the horizon? I’m waiting for the first cheap desktop solid modeling printers to hit the market so I can crank out 3D models of my favorite fishing holes. Canon? Epson? HP? Anyone?

– Brian


The Frost Course

…or how I learned to live on coffee and Tylenol for two weeks.

In the military there are certain rights of passage, like your graduation parade at the end of basic training, or making your fifth parachute jump and getting your silver parachutist wings, or getting your butt chewed by the First Sergeant for showing up late for formation, or going down to Yadkin Road and getting your first tattoo (you old Fort Bragg veterans will know what I’m talking about).

In my old field, terrain analysis, one of the rights of passage was successfully completing the Frost Course. No, the Frost Course didn’t have anything to do with the weather, and it wasn’t a poetry reading class. The Frost Course was considered a master class in the use of stereo aerial photography for landform analysis and military terrain analysis.

The course was developed by Dr. Robert E. Frost while working for the US Army’s Engineer Topographic Laboratories (ETL) where he headed up ETL’s Center for Remote Sensing.


As I once heard Dr. Frost explain it, the analyitical techniques taught in the course were developed over several decades of research based on aerial photo analysis in support of a wide variety of military and civil projects for the Army Corps of Engineers. His work dated all the way back to WWII and Purdue University, where he pioneered many of the aerial photo pattern analysis and terrain analysis techniques that would become the backbone of later Army terrain analysis training.


Dr. Frost began his career at Purdue University, where pioneering research in the use of aerial photography for terrain and resources analysis began in the late 1920’s.  Frost worked at Purdue with both Professor Bushnell and another aerial photo analysis pioneer, Dr. Donald Belcher before moving over to the Army Corps of Engineers


L1/Korean War 1950-1953/pho 28

During WWII the Army Corps of Engineers vastly expanded the use of aerial photography for mapping and terrain analysis. This demand was triggered by pioneering work done in the 1935 – 1941 time period by both Army topographic engineers and researchers at places like Purdue University who developed the aerial camera systems and analytical processes and tools needed to exploit this new resource

Dr. Frost noted that he expanded this work into historical terrain analysis while acting as an expert witness in a string of court cases brought against the Corps of Engineers. Starting in the 1970’s the Corps of Engineers became a favorite target of the environmental movement. The Corps was an easy mark. It was involved in billions of dollars of public works projects across the United States, most involving waterways improvements. In mid-20th century parlance ‘improvements’ mean draining wetlands, building dams and levees, dredging rivers and digging canals. A favorite joke of the day went like this: “Why don’t Corps of Engineer officers help their wives with the dinner dishes? Because they can’t stand the sight of running water!”

At some point the Corps of Engineers turned to Dr. Frost to see if he could develop evidence to prove that Corps projects were not responsible for the impacts the plaintiffs were seeking damages for. Dr. Frost figured the best way to approach the problem was to look at the history of the project areas as shown in successive years of aerial photography and try to determine the what was causing the issues the land owners and environmentalists were so upset about. Dr. Frost and his team at the Center for Remote Sensing went through the vast aerial photo archives of the the USGS, NOAA, the Soil Conservation Service, the Department of Agriculture, the Tennessee Valley Authority, state and local agencies, private aerial survey companies and even the Corps of Engineers’ own holdings to build a library of historical aerial photography covering various Corps’ project areas. Much of this photography went back into the 1930’s and predated by decades the projects that were in dispute.

Dr. Frost’s team then applied the aerial photo analysis techniques developed over decades of research and field study to establish a terrain analysis ‘timeline’ of the changes that took place over the project areas. More often than not Dr. Frost and his team were able to prove that the Corps of Engineers’ activities were not the proximate cause of the issue. Things like historical land use changes, flood and drought cycles, poor erosion control, poor land management practices or other human or environmental impacts that had nothing to do with the Corps’ activities were frequently identified as the root cause of the problem.


OK, who’s gonna’ pay?

In the late 1970’s the Army recognized the growing demand for terrain analysis products needed to support military planning and operations. The decision was made to establish Engineer terrain analysis teams at the division, corps and echelons above corps levels. The analysis processes the Soldiers in these units used were based on techniques developed by ETL’s Terrain Analysis Center. Dr. Frost and the Center for Remote Sensing were key resources the Terrain Analysis Center turned to for help developing the aerial photo analysis techniques that needed to be taught to the hundreds of enlisted analysts and warrant officer candidates that would make up these new terrain analysis teams.


Germany 1985. Soldiers of the 517th Engineer Detachment (Terrain Analysis) use a zoom transfer scope (ZTS) to create terrain overlays using aerial photography. The study was done to support the V Corps REFORGER 85 exercise. The overlay will depict soil types that are least able to support off-road vehicle traffic. The techniques used to analyze the imagery were developed by Dr. Frost and his team at the ETL Center for Remote Sensing and the ETL Terrain Analysis Center. CW2 Tim Butler, the detachment’s terrain analysis technician and an early graduate of the Frost Course, is at the ZTS


The resulting analysis for REFORGER 85 was used daily to predict areas at high risk for maneuver damage based on soil type, moisture content and ground temperature.  After the exercise V Corps announced that this analysis saved an estimated $1 million dollars in maneuver damage claims compared to previous REFORGERs

At some point Dr. Frost decided to package his experience and analysis techniques as a formal class, and the Frost Course was born. This course took the elementary photo analysis processes taught in the terrain analysis classes at the Defense Mapping School and expanded them to cover a wide range of topics beyond military applications, adding course content in geology, soils science, forestry, agriculture, hydrology, transportation and urban analysis. Woven into the course were college-level requirements in analysis, research and thesis defense.  It was a master class in aerial photo analysis for topographic and terrain analysis.


Dr. Frost’s ‘Statement of Principles’ for the Frost Course

Starting in the early 1980s Dr. Frost taught his class regularly at the Defense Mapping School (DMS) at Fort Belvoir, VA. Unlike so much US Army military training at the time the Frost Course was actually challenging; Dr. Frost forced you to analyze and think. There were no multiple choice questions in his course. You discussed a particular terrain issue, reviewed applicable analytical techniques, were presented with a problem, sent off to do the analysis and then came back to present your results and defend your conclusions. While you couldn’t actually fail the Frost Course, the competition to get into the class was so tough that only highly motivated Soldiers attended, so the quality of the output – skilled terrain and topographic analysts – was quite high.

The Frost Course was taught in modules (called ‘Problems’), with each module teaching a particular analytical process based on things like landform, pattern, hydrological, transportation or urban analysis. Each module consisted of some instructional material, references, an assignment sheet and a set of stereo aerial photos.

Frost Course Module 3

Frost Course Problem 3, Pattern Recognition


Frost Course Module 3 blow-up

Problem 3 required detailed analysis of a stereo triplet to determine the landforms, drainage, vegetation, cultural and land use patterns. These are current photos taken of the coursework I completed in 1995.

The joke was that when you showed up for the Frost Course you got issued two things – a pocket stereoscope and large bottle of Tylenol. That’s because you spent 6 hours each day in class staring at stereo photos and then you went home and spent another couple of hours peering through the stereoscope as you worked on your homework assignment. Headaches due to eye strain were the norm.

Marty Feldman

Frost Course, Day 1 – eyestrain is starting to set in…

I met Dr. Frost back in 1982 when he visited us at Fort Bragg. The Engineer Topographic Laboratories (ETL) sent him to pitch the idea of having him teach his class at Fort Bragg. The Army had a growing demand for terrain analysts and DMS couldn’t train them fast enough. The idea was that the Frost Course would enhance the skills of the terrain analysts already assigned to Fort Bragg, provide a good foundation of skills for those Engineer Soldiers interested in becoming terrain analysts and provide additional training to a number of photo interpretation analysts from the Intelligence units on Fort Bragg. It was far cheaper to bring Dr. Frost to the students than it was to send the students to Dr. Frost. Sadly, the senior Engineer commanders on Fort Bragg disagreed and the idea was nixed. The XVIII Airborne Corps Assistant Corps Engineer at the time commented, “Why should we pay for training these guys (terrain analysts) already get when they go to DMS?” Obviously this idiot wasn’t listening when Dr. Frost clearly and concisely laid out the differences between what our terrain analysts learned in their basic classes at DMS and what his course provided.

Over the next decade I sent dozens of Soldiers from my units to the Frost Course at DMS. While many of my battalion and brigade commanders questioned the value of the course I knew that the Soldiers would come back better analysts. Being selected to attend was viewed as recognition that a Soldier was ‘on his (or her) way’; headed for greater rank and responsibility. I even used attendance at the Frost Course as a reenlistment incentive – “Pssst – hey Specialist Jones, sigh up for another three years and I’ll get you a seat in the next class.” It was surprising the number of Soldiers who took the offer.


Another Soldier, SPC Cantu, reenlists for the Frost Course. In this case I was even able to wrangle him an assignment to the Topographic Engineering Center. He still owes me a beer

But I never got to take the course from Dr. Frost. I would send Soldiers at the drop of a hat but my superiors never seemed to think it important that I attend. Dr. Frost retired in 1990 but before he left he handed responsibility for teaching and updating the class over to Major John Jens, who worked at the Topographic Engineering Center (the successor to ETL) at Fort Belvoir. In 1995 I was sent to the Defense Mapping School for my Warrant Officer Advanced Course. Since only two of us showed up for the Advanced Course that year the course coordinator had little for us to do. We were supposed to work on a nebulous ‘research paper’ but that was it. I could have wandered the hallways and counted floor tiles for a month and still graduated at the top of my class. One day right after I arrived I picked up a DMS course catalog and saw that John Jens (now retired) was scheduled to teach the Frost Course the next week. I looked over at the course coordinator and said, “I’ve never been through the Frost Course. I think I’ll sit in on it.” “Sure,” he replied “sounds like a good idea.” He went back to his Washington Post crossword puzzle relieved that he wouldn’t have to babysit me for another few weeks.

A month ago I was going through some old Army paperwork and unearthed all of the Frost Course modules I worked on in John Jens’ class back in 1995. Looking through the aerial photos and study papers triggered a wave of nostalgia and caused me to write this post. But more to the point, since 1995 I’ve had literally hundreds of hours of additional education and training in terrain analysis, geospatial analysis, graduate level work in geography, geodesy and surveying and a broad range of industry specific geospatial software training. I can honestly say that nothing I’ve been taught since 1995 has approached the analytical rigor that the Frost Course demanded. It was (and hopefully still is) that good.

– Brian