Ground Sensor Lifer

The view from our “room” in Musa Qala, Afghanistan.

History is full of examples of successful military surprises.  Examples of effective early warning strategies are more difficult to find, but they range from the simple to the sublime. Animals such as dogs, horses, and even guinea hens have been used to warn of the enemy’s approach. According to the ancient historian Livy, the Romans used geese to detect a night attack on Rome by the Gauls in the 4^th century BC. Trip wires and noise makers are another classic example of long-used early warning devices. Don’t forget scouts and observation and listening posts. As early as the Vietnam War, radio and electronic detectors were also used to alert the presence and movement of men and materiel.  

High ground has always been considered essential for observation, usually supplemented by watchtowers, like those positioned along Hadrian’s Wall in Britain and the Great Wall of China. Aviation took high ground to another level. In May 1863, an observation balloon of the Army of the Potomac detected General Lee’s Army of Northern Virginia moving across the Rappahannock to engage in the Gettysburg Campaign.

USMC Early Warning Capabilities

Remote sensor capabilities entered the scene in September 1966 when Secretary of Defense Robert McNamara established the Defense Communication Planning Group (DCPG). The DCPG was tasked with developing a system to monitor the movement of supplies and men from North Vietnam to South Vietnam via the Ho Chi Min Trail. Under their auspices, the Navy was tasked to develop an RSS (Remote Sensor System) for deployment in Vietnam later that year.

The first operational sensors were deployed thirteen months later. The Air Force utilized intelligence collected from the sensors to direct strike aircraft onto enemy targets. In response to the mounting pressure on the Marines fighting at Khe Sahn, elements of the RSS were redirected to support them.

Seismic and acoustic sensors were air delivered and emplaced by ground reconnaissance elements around the 26^th Marine Regiment’s defensive perimeter, focusing on possible ingress/egress routes. As the North Vietnamese began to attack, the sensors provided a limited role in intelligence collection on enemy artillery and mortar positions. However, their value regarding enemy movement contributed to the Marine victory.

What is USMC Ground Sensor Platoon today?

2nd GSP platoon pic, a week before we deployed to Iraq.

Fifty years later, Ground Sensor Platoon has morphed into a small specialized unit that seeks out and monitors insurgency and high-value targets for offensive operations. They also prevent larger-scale infantry units from ambush, improvised explosive devices, or other types of attacks. GSP is classified as an intelligence unit but holds firm to our infantry background.

A GSP team consists of four Marines, three 0311s (Infantry), and one 0621 (Radio Operator). Teams are usually led by a Corporal (E-4) or Sergeant (E-5). On deployment, teams are individually attached to an assigned infantry battalion in an AO (Area of Operations). Although the role of sensors is primarily surveillance, target indication, and early warning, they can and have been utilized in many more roles, such as force protection, sniper support, and target visual identification (VID).

8621 Training

To obtain my secondary Ground Sensor MOS and security clearance, I was ordered to attend an eight-week Sensor Surveillance Operators Course (SSOC) at the Navy/Marine Corps Intelligence Training Center (NMCITC) in Dam Neck, VA. I learned basic intelligence, mapping, equipment, planning, monitoring, reporting, and emplacement techniques. The training gave me the ground-level skills to deploy ground sensors in combat operations.

Diversionary Tactics

Picture by Thumper of the terrain surrounding Now Zad.

I’ve employed ground sensors in several countries for various missions. Each country had its own set of challenges. In Afghanistan, the terrain was medieval. I vividly remember using my E-Tool for the first time and feeling like I was mining for precious metals. It was loud, and it was hard. It was volcanic rock, devil’s ground.

There was the terrain and the local population, but they rarely ventured beyond their village or town. Because of this, they knew every blade of grass, every rock formation, and every disturbance to the land. We had to use diversionary tactics to insert our team, usually in the dead of night.

An example is a mission we conducted with Sniper Team 4, “Erebus 4”. Our mission was to deploy a Scorpion sensor equipped with a day and IR camera. The S-2 wanted our team to surveil a village east of the Musa Qala District Center. Snipers would provide overwatch.

At 0200, we set off from the District Center in a five-vehicle (MATVs) mounted patrol. The patrol advanced to a position west of and overlooking the village next to a wadi. It was a good 50-foot drop to the bottom of the valley floor if you lost your footing. The patrol came to a halt on a strip of road out of view of the village below. EOD was in the lead vehicle, and they pushed forward 200 meters while the remaining vehicles stayed static. Ten minutes later, a massive explosion broke the silence of the night. That was our cue. EOD had set off a controlled detonation up ahead. We dropped off the vehicles and crept towards the ridgeline, establishing a 360-degree defensive position. There were six of us, four snipers, and two sensor operators. The remaining vehicles took off like a bat out of hell, providing a mini sandstorm that covered our team’s movement. Diversion executed.

As the sounds of the escort patrol disappeared, I started to see lights flashing on and off on the opposite ridgeline. First, it was a flash off to the right, then two flashes off to the left. It looked like the Taliban was directly in front of our insert position. I thought to myself, “Fuck, they saw us.” We observed for a couple of hours, and the lights finally dimmed.

Tools of the Trade

TRSS

One of the few times I marched the platoon during training in Quantico, VA.

I was trained on Tactical Remote Sensor Systems (TRSS) sensor system in Dam Neck. TRSS systems include seismic, acoustic, magnetic, infrared sensors and surveillance cameras. These sensors could detect the presence and movement of personnel and vehicles and provide near real-time monitoring of sensor activity within line-of-sight of a radio repeater or the TOC (Tactical Operations Center).  TRSS provides a surveillance capability without maintaining a physical presence in the immediate target area.

The downside to TRSS was that sensors in the field had to maintain a line of sight with a radio repeater or the TOC (Tactical Operations Center). If I didn’t have line-of-sight, the sensors wouldn’t report. It was a pain in the ass, especially in mountain terrain. The other limitation was the battery life of the sensors, and there wasn’t an alternative power source, such as a solar or rechargeable battery.

SatCom (Satellite Communications) Systems

During my pre-deployment training for Iraq, I was introduced to SatCom Systems. The difference between the two systems was huge. SatCom sensors provided day and night imaging and an advanced acoustic sensor with a more sophisticated target classification capability and target location. The SatCom sensors I operated had a much longer battery life than TRSS sensors, especially for the systems with an external battery pack with six 5590 batteries. It could stay in the field much longer.

SatCom systems were also great because I could program the system in the field and only have to worry about line of sight with the satellites in the sky. It’s much less challenging, line-of-sight wise. Deploying one of these could be done relatively quickly…unless you ran into Murphy and his bullshit law. Plug batteries into System, Load your program, Site the cameras in, and ensure you have good images, camouflage, police area, and exfil. It was as easy or hard as that, depending on Murphy.

The downside to SatCom systems was the size of the unit and cameras (Day/IR). We had to learn to camouflage our systems to blend in with the local topography.  To aid us in camouflage, we were issued fake silicon rocks. The Afghans would have spotted those things from a mile away. We favored using our own homemade solutions. We used spray foam to build a “honeycomb” over the lens of the camera, leaving just enough of a hole for us to receive good, clear images.

Hiding Gear in the Suck

SatCom camera camouflaged with spray foam. We deployed this system in Salaam Bazaar.

One of the many problems I encountered in the Middle East was that the people lived in one place and didn’t move around much. They weren’t exactly taking holiday vacations to different provinces. It was too dangerous. The locals knew the land like the back of their hands. It’s challenging to hide a bulky ground sensor in the ground without someone noticing it. We were doing the same thing as the insurgents who dug in IEDs, except we didn’t know the ground like the enemy.

In Afghanistan, we deployed a string of ETU II (Encoder Transmitter Unit) sensors that were compromised by the Taliban and booby-trapped with six pressure plate IEDs. That could have been game over. It was the Taliban “Counter Sensor Teams,” the bastards. We knew we were being watched everywhere we went. It was a deadly game of cat and mouse.

I cherish my years in GSP, even though I bitched and moaned through most of it. I faced a lot of fears. I’ve been on teams that meshed really well, understood each other’s role in the team, and operated as one cohesive unit. I’ve also been on teams that were like a toxic relationship. That’s just the way it is. I miss the guys most of all. 

Sources

Bradley C. Palm, and Ryan P. Richter. “Mobile Situational Awareness Tool: Unattended Ground Sensor-Based Remote Surveillance System.” PhD diss., Naval Postgraduate School, September 2014.

U.S. Marine Corps: Department of the Navy. “Remote Sensor Operations.” MCRP 2-10A.5, April 4 2018.

Department of the Navy: HQ USMC. “Ground Sensor Surveillance T&R Manual.” NAVMC 3500.17A, September 2010.

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