Role and Responsibilities of a 13B Cannon Crewmember in the US Army

In the United States Army, the Military Occupational Specialty (MOS) 13B identifies the Cannon Crewmember. This role serves as the backbone of the Field Artillery branch, often referred to as the "King of Battle." A 13B is responsible for operating, maintaining, and firing high-tech cannon artillery weapon systems, primarily howitzers, to provide long-range fire support for infantry and armored units during combat operations. While the infantry engages the enemy at close range, the 13B provides the overwhelming firepower necessary to suppress enemy movement, destroy fortified positions, and secure the battlefield from miles away.

Defining the 13B Cannon Crewmember

The 13B Cannon Crewmember is an integral part of a field artillery gun section. Unlike many roles that rely on individual performance, the 13B operates within a tight-knit team where synchronization is a matter of life and death. The primary mission of these soldiers is to deliver indirect fire, meaning they hit targets they cannot see, relying instead on coordinates and data provided by Fire Direction Centers (FDC) and Forward Observers (FO).

Artillery has evolved significantly from the era of simple cannons to modern, computerized systems capable of hitting a target with surgical precision. The 13B must be adept at both the raw physical labor of manual gunnery and the technical sophistication of digital fire control systems. Whether they are operating a towed howitzer in a dense forest or a self-propelled Paladin in the desert, their role is to ensure that when the command "Fire" is given, the round lands exactly where it is needed.

Core Duties and Daily Operations

The daily life of a 13B varies between garrison (home base) and field environments. However, their primary duties revolve around the weapon system and its ammunition.

Operating Howitzer Systems

The most visible duty of a 13B is the operation of the howitzer. This involves several technical steps:

• Emplacement: When a battery moves to a new location, the crew must "emplace" the gun. For towed artillery, this means unhooking it from a prime mover, digging in the spades to prevent the gun from jumping during recoil, and orienting the piece toward the expected target area.
• Laying the Piece: Using sights and digital systems to align the cannon tube with the correct direction (azimuth) and elevation.
• Firing: Pulling the lanyard or activating the electronic trigger to send a projectile downrange. This requires constant communication within the crew to ensure the correct data is set.

Ammunition Management and Preparation

Handling ammunition is one of the most physically taxing parts of being a 13B. A standard 155mm high-explosive projectile weighs approximately 95 pounds. Crewmembers must:

• Identify Rounds: Distinguish between High Explosive (HE), White Phosphorus (WP), Illumination, and Smoke rounds.
• Set Fuses: Manually or electronically program fuses to explode on impact, at a certain height above ground, or after a specific delay.
• Prepare Charges: Select the correct amount of propellant (powder) needed to reach the target’s distance. Too much or too little powder can lead to missing the target or endangering friendly troops.

Field Maintenance and Security

Artillery pieces are complex machines that require constant upkeep. 13Bs perform "operator-level" maintenance, which includes cleaning the tube (swabbing the bore), checking hydraulic fluids, and ensuring the breach mechanism functions smoothly. Additionally, because artillery units are high-value targets for enemy forces, 13Bs are responsible for their own security. This includes:

• Perimeter Defense: Setting up machine gun positions (M240B or M2 .50 cal) around the firing point.
• Camouflage: Using nets and natural vegetation to hide the gun and vehicles from aerial and ground observation.
• Reconnaissance: Participating in "Recon, Selection, and Occupation of Position" (RSOP) to find the best spots for the battery to operate.

The Weapon Systems of the 13B

A 13B soldier will typically specialize in one of three primary cannon systems used by the U.S. Army. The specific unit a soldier is assigned to usually determines which system they will operate.

M119A3 105mm Towed Howitzer

The M119A3 is a lightweight, highly mobile towed howitzer primarily used by Airborne, Air Assault, and Light Infantry Brigades.

• Capabilities: It is designed for rapid deployment, often via helicopter (sling-load) or parachute drop.
• The 13B Role: Because it is smaller, the crew for an M119 is typically smaller and must be exceptionally fast. It is used for close-in fire support where speed and mobility are more important than massive destructive power.

M777A2 155mm Towed Howitzer

The M777 is the workhorse of the medium-force artillery. Constructed largely of titanium to reduce weight, it delivers 155mm shells with devastating effect.

• Capabilities: Despite its size, it can be transported by heavy-lift helicopters and transport planes. It is famous for its digital fire control system, which allows it to fire GPS-guided Excalibur rounds that can hit within meters of a target from over 20 miles away.
• The 13B Role: Operating the M777 is a rhythmic, team-based process. Soldiers must manage the massive "spades" that hold the gun in place and handle the significantly heavier 155mm ammunition.

M109A6/A7 Paladin Self-Propelled Howitzer

The Paladin looks like a tank but is actually a mobile artillery piece. It is an armored vehicle with a 155mm cannon mounted in a turret.

• Capabilities: It provides protection for the crew and can move, fire, and move again (shoot and scoot) within minutes to avoid counter-battery fire.
• The 13B Role: Inside a Paladin, the 13B operates in a cramped, noisy environment. They must also be proficient in vehicle maintenance, as the Paladin is both a weapon system and a heavy tracked vehicle.

Training Path for a 13B Cannon Crewmember

Becoming a 13B requires a specific training pipeline designed to transform a civilian into a "Red Leg"—the traditional nickname for artillerymen.

Basic Combat Training (BCT)

All 13B candidates begin with 10 weeks of Basic Combat Training. This phase focuses on general soldiering skills, including physical fitness, marksmanship with the M4 carbine, land navigation, and the Army's values.

Advanced Individual Training (AIT) at Fort Sill

After BCT, 13B soldiers move to Fort Sill, Oklahoma, for five to seven weeks of Advanced Individual Training. Fort Sill is the historic home of the Field Artillery.

• Week 1-2: Classroom instruction on the basics of artillery, including the math behind firing, types of projectiles, and safety procedures.
• Week 3-4: Hands-on training with the specific weapon systems. Soldiers learn how to "lay" the gun and the mechanics of the breech and loading tray.
• Week 5+: Live-fire exercises. This is where the training culminates in actual firing of rounds. Soldiers experience the concussive force of the blast and the pressure of working in a "fire mission" under time constraints.

The Physicality of 13B Training

The Army classifies the 13B MOS as "Very Heavy" in terms of physical demand. Trainees must demonstrate the ability to lift and carry heavy shells repeatedly. A 13B who cannot keep up with the physical demands of loading the gun becomes a bottleneck for the entire section, which can be catastrophic in combat.

Qualifications and Requirements

Not everyone is eligible to become a 13B. The Army sets specific standards to ensure candidates can handle the technical and physical rigors of the job.

ASVAB Scores

To qualify for 13B, a recruit must take the Armed Services Vocational Aptitude Battery (ASVAB). Specifically, they need a score of 93 in the Field Artillery (FA) category. This category measures aptitude in arithmetic reasoning, mathematics knowledge, and mechanical comprehension.

Physical and Medical Standards

• Strength: Must be able to lift and move objects weighing over 100 pounds.
• Vision: No color blindness (must be able to distinguish between red and green for signal flares and markings).
• Hearing: Must have adequate hearing to receive voice commands over the roar of artillery fire.
• Citizenship: Generally requires U.S. citizenship or a valid green card, though certain security clearances for advanced systems may require full citizenship.

Career Progression and Opportunities

The career of a 13B follows a structured path of increasing responsibility, moving from the physical execution of fire missions to the management of entire artillery sections and platoons.

Junior Enlisted (PV1 to SPC/CPL)

At these ranks, the 13B is a "doer." They are the ones loading the rounds, setting the fuses, and digging the spades. They are learning the nuances of the gun and ammunition.

Non-Commissioned Officer (SGT to SSG)

• Gunner: The Sergeant (E-5) usually serves as the Gunner. They are responsible for the actual aiming of the piece and ensuring all data entered into the sights or computer is correct.
• Section Chief: The Staff Sergeant (E-6) is the "manager" of the gun section. They supervise everything from maintenance to the safety of the fire mission. The Section Chief is responsible for the lives of their crew and the accuracy of the rounds.

Senior NCOs (SFC to CSM)

• Platoon Sergeant: A Sergeant First Class (E-7) oversees several gun sections. They handle the logistics, movement, and tactical deployment of the platoon.
• Master Gunner: A highly specialized role for senior NCOs who become the ultimate technical experts on the weapon systems, advising commanders on the best use of artillery.

Broadening Assignments

Experienced 13Bs can serve as:

• Drill Sergeants: Training the next generation of soldiers.
• Recruiters: Finding new talent for the Army.
• Observer/Controller/Trainers (OC/T): Evaluating other units during large-scale training exercises at places like the National Training Center (NTC).

Compensation and Benefits

A 13B's pay is based on the standard U.S. Army pay scale, determined by rank and years of service.

• Base Pay: Ranges from approximately $2,017 per month for a Private (E-1) to over $5,000 per month for senior NCOs.
• Allowances: Soldiers receive Basic Allowance for Housing (BAH) and Basic Allowance for Subsistence (BAS) if they live off-post.
• Special Pay: 13Bs may be eligible for Hostile Fire Pay or Imminent Danger Pay when deployed to combat zones.
• Education: Through the Post-9/11 GI Bill, 13Bs can earn full college tuition after completing their service.

The Reality of Being a 13B: Physical and Mental Impact

While the "King of Battle" title is prestigious, the reality of the job is grueling.

• Environmental Extremes: Artillery missions happen in rain, snow, or extreme heat. 13Bs spend weeks in the field sleeping in tents or on top of their vehicles.
• Physical Toll: Years of lifting 95-pound shells and jumping off large trucks can take a toll on the back and knees.
• Sensory Intensity: Even with ear protection, the sound of a 155mm howitzer is bone-shaking. The smell of burnt powder and the grit of diesel exhaust are constants.
• Team Bond: Because they live and work in small "gun crews," 13Bs often form the tightest bonds in the Army. A gun section is a family that eats, sleeps, and fights together.

Transitioning to Civilian Life

One common question for prospective 13Bs is how the skills translate to the civilian world. While "firing a howitzer" isn't a civilian job, the underlying skills are highly marketable:

• Heavy Equipment Operation: Experience with the Paladin or the prime movers (large trucks) translates to construction or logistics.
• Logistics and Inventory: Managing thousands of pounds of ammunition and fuses is directly applicable to warehouse and supply chain management.
• Team Leadership: Leading a 10-person crew in high-pressure environments is a skill valued in project management and emergency services.
• Technical Maintenance: Understanding hydraulic and mechanical systems is useful in industrial maintenance and mechanical trades.

Conclusion

The 13B Cannon Crewmember is a role of high stakes and high physical demand. These soldiers provide the massive, long-range firepower that defines modern warfare. From the grueling training at Fort Sill to the precision required in a live fire mission, the 13B embodies the strength and technical skill of the Field Artillery. For those who enjoy working in a team, handling heavy machinery, and being at the heart of the Army's combat power, the 13B MOS offers a challenging and rewarding career path.

Summary Table: 13B at a Glance

Frequently Asked Questions (FAQ)

What is the difference between an 11B and a 13B?

An 11B (Infantryman) engages the enemy directly with small arms (rifles) and is typically on the front lines. A 13B (Cannon Crewmember) provides indirect fire support from a distance using large-caliber cannons to destroy targets that the infantry might be facing.

Is 13B a dangerous job?

Yes. As a combat MOS, 13Bs are often targeted by enemy counter-battery fire (enemy artillery trying to hit them back). They also work with high explosives and heavy machinery, which carries inherent risks.

Where do 13B soldiers get stationed?

13Bs can be stationed at almost any major Army installation with a combat mission, including Fort Liberty (formerly Bragg), Fort Cavazos (formerly Hood), Fort Carson, and overseas locations like Germany, South Korea, and Hawaii.

Do I need to be good at math to be a 13B?

While the Fire Direction Center (FDC) does the most complex calculations, a 13B still needs a basic grasp of mathematics to verify data, set fuses, and ensure the gun is laid correctly. The ASVAB FA score of 93 ensures you have the necessary aptitude.

What is a "Red Leg"?

"Red Leg" is a traditional nickname for Field Artillery soldiers. It dates back to the American Civil War when artillerymen wore a red stripe down the side of their uniform trousers to distinguish them from other branches.