Happy Belated Veterans Day: GIs and GPS

By Joe Summerlin

A few years ago, I found myself trekking along Town Branch Creek in Bolivar, Missouri noting areas that were impaired, taking photos, and storing waypoints on my smartphone. I mused at how easy it was to load information and tell a story about this little watershed from a device that fit firmly in the palm of my hand. Then it dawned on me. Just fifteen years earlier, I had witnessed the birth of handheld GPS devices in the U.S. Army. I then thought, “I am getting old. Maybe some of the younger generation would like to know about the predecessor to devices they take for granted today.” This blog will discuss the capabilities of handheld GPS devices in the early 1990’s, specifically the Precision Lightweight GPS Receiver (PLGR.)

The PLGR or “plugger” was one of the first mass produced handheld GPS devices used by conventional forces in the U.S. Army. It saw its first real combat test in 1991 during the Gulf War. The concept was simple: use existing military and secure government satellites to orient a soldier on the battlefield. At the time there were 24 satellites in orbit and this puppy needed three for accurate lat/long data or four for lat/long plus elevation data.

Many of the negative characteristics of the design of this beast were made by engineers to ensure longevity and meet the requirements set by U.S. Army leaders. Note the lack of a full color display. This was designed on purpose using liquid crystal displays to ensure an ambient light source would not give away the positions of soldiers on the field. This also made it incredibly difficult to read where you were. The display was also compatible with night vision goggles. Unfortunately, I always peeked under my goggles and pushed the “light” button or used a red-filtered lens and shined it on the display.

The PLGR was bulky, boxy and not a product to sell to the masses. The buttons were clunky and there were only twelve. In order to store a waypoint you had to arrow through a bunch of poorly written menus. Sometimes when you wanted to store a waypoint, you would find yourself scrolling through a menu for 10 minutes. When you did actually store a waypoint, you would have to clunk your way back to the main menu by using a series of guesses, some luck, and maybe some sort of magic ritual. My secret was to hit the power button and wait for the 7 minute reboot.

I haven’t even touched on the size of this monster. Hand held – yes, only if you had Shaquille O’Neal-sized hands. The PLGR weighed a mere 2.75 pounds or about the equivalent of one canteen of water.

The PLGR was large for two reasons. First, micro technology was not as advanced, and second, soldiers lose small items. It used 634 AA batteries (maybe it just seemed like it did) and the battery life was about 2 hours. We learned to conserve battery power by turning it off and using the maps in our pockets. Only when we were lost (which never happened because we are the U.S. Army) did we pull it out to get our bearings.

Well, there you have it, the smartphone’s grandpappy. Next time you are in the car listening to that speak n’ spell voice demanding “TURN RIGHT,” just think to yourself, if it weren’t for the military and those veterans that tested and used this stuff I might have just made a left turn at Albuquerque.

 

Joe Summerlin is an Environmental Scientist in EPA Region 7 who works with the Agency’s NEPA program. He served in the U.S. Army for 14 years as a Cavalry Scout and a CH-47D Chinook  helicopter pilot.