M2A3 BFV Master Gunner's Course Overview

M2A3 BFV Master Gunner's Course: Sustainment and Diagnostics

• Course Focus: Sustainment and diagnostics of the M2A3/M3A3 Bradley Fighting Vehicles (BFV).

• System Status Information: The system status/information is displayed as "A3 BRADLEY". The document also notes "NBIT is abortable".

Terminal Learning Objective

• Action: Maintain a M2A3/M3A3 BFV.
• Conditions: Given classroom instruction, student guide, TM 9-2350-438-10, a fully operational M2A3 BFV, and a M2A3 desktop trainer.
• Standards: Maintain a M2A3/M3A3 BFV through sustainment and diagnostics on a BFV IAW student guide and TM 9-2350-438-10.

Learning Step Activity 1: Describe the Component Functions of the Power Management/Distribution Subsystem (PMDS)

• Reduced White-Smoke Engine: The M2A3/M3A3 has a reduced white-smoke engine. The Step Timing Control cuts in within 25 seconds after engine start, reducing smoke and altering engine sound.
• 400 Ampere Generator: Provides regulated +28 VDC electrical current to charge turret reserve, turret electronics, and hull batteries.
• TEC Transmission – Electronic Controlled Braking: The transmission (TEC) consists of a transmission, interface assembly (IA), interface cable, electronics assembly (EA), and the Bradley Shift Tower (BST). The EA, located beneath the shift tower, controls the transmission based on the gear selector position.

Learning Step/Activity 1: Describe the Component Functions of the (PMDS) - Additional Details

• Bradley Shift Tower (BST): Located on the driver's right side.
• Electronics Assembly (EA): Attached to the BST, monitoring lever position and transmitting the gear selector position via interface cable to the interface assembly.
• Engine Start Procedure: This includes steps to turn on master power, checking the BST light (ensure it is flashing), setting the engine accessory switch to ON, pushing the fuel cut-off handle, pushing the BST handle to start the engine, checking the engine and transmission gauges on the Driver's Tactical Display (DTD), and ensuring the BST light turns off within 22 seconds.

Learning Step/Activity 1: Vehicle and Turret Batteries Viewgraph

• 24-VDC Turret Reserve Battery: Supplies power to the turret.

• Turret Electronics Batteries (2): Provide power to essential turret components.

• Hull Batteries (4): Provide power to the vehicle; includes two batteries mounted on the left sponson and four beneath the driver. The two sponson-mounted batteries are referred to as the Turret Electronic Batteries.

• Digital Vehicle Distribution Box (DVDB): Distributes power, provides circuit breaker protection to hull electrical subsystems, and stores test programs for embedded diagnostics.

Learning Step/Activity 1: Component Functions (PMDS) Additional

• Power Distribution Box (DVDB): Distributes power to various LRUs (Line Replaceable Units) and electrical systems including the Cold Start Distribution Box and Smoke Generator Solenoid. It also powers components such as Ramp Pump Motors, Hull Ventilation Fans, Bilge Pumps, Fire Suppression System, Winterization Kit, Emergency Shutdown Switch, Fuel Pumps, Engine Sensors, Driver's Instrument Panel Gages, Hull Dome Lights, Gas Particulate Filter Unit, Personnel Heater, Hydraulic Engine Access Door, and Slave Start System.

Learning Step/Activity 1: Additional Information

• Hull Power Box (HPB): Controls, distributes, protects, and isolates power to all PCMs (Power Control Modules); receives power from turret electronics batteries and the other hull batteries through an isolation circuit from the generator.

• Turret Power Box (TPB): Protects and distributes high current turret loads; receives power from the hull batteries, the generator, and the turret battery.

• Power Control Modules (PCMs): Distribute power to electronic components within the vehicle; there are two PCMs in the turret and one in the hull (PCM1, PCM2, and PCM3).

• Common Capabilities of PCMs: Load Switching, No Load Status, On/Off Status, Overload Protection, Short Circuit Protection, Ground/Open outputs, 28-volt/Open inputs, Built-in Test (BIT), Mil-Std-1553 Data Bus Interface, and On-Board Reprogramming.

• Turret Processor Unit (TPU): The Primary Mission Computer takes over as the Bus Controller (Provides the communication network), after power-up is complete. Houses the Fire Control Processor card (for super elevation corrections and kinematic lead). The TPU also stores various pieces of information (e.g. Fire Control, Navigation, BIT data from Test Management Diagnostic Equipment).

• Slip Ring (SLR): Interconnects power, signal, video, and CBRN air between hull and turret.

Learning Step/Activity 2: Modes of Operation and Types of BIT's

• Modes of Operation: Power-up Sequencing, Controlled power-down, uncontrolled power-down, and silent watch state.
• Types of BITs: Startup BIT (SBIT), Non-Interactive BIT (NBIT), Background BIT (BBIT), Interactive BIT (IBIT), and Fault Isolation Test (FIT).
• Emergency Turret Shutdown Switch: Enables GNR/BC to shut down turret power in emergencies.
• Data Deletion Switch: Eliminates data in the TPU, INU data (BIT, boresight), alignment constants, and DAGR encryption keys and coordinates.

Learning Step/Activity 3: Describe the Failure Handling Process

• Failure Handling Process: When a critical failure is detected, it automatically moves the vehicle to Safe Mode, inhibiting turret drive and weapon-firing functions. In Safe Mode, the system disables weapons systems until corrective action or a reset is performed.
• Failure Handling Messages: The system displays pop-up messages (Loss, Exception, etc.) on CTD and may sound an audible signal if indicated.
• Accessing Malfunction Advisory List: The maintainer can access a Malfunction Advisory List (using the CTD) to view all failures that have occurred and their locations.
• Malfunction Indications: Loss, Degraded, Verify, Go, and No Go status conditions may activate or deactivate components or system-level functionalities; the MAL indicator increments for each failure, loss of functionality, or safety-related warning.
• Typical Failure Handling Scenarios: LOSS, SAFETY SENSOR AND INTERLOCK, DEGRADED, and NOGO conditions are used to indicate malfunctions or required action.
• Annunciator Light Activation: A flashing "M" in the IBAS/CIV sight indicates a safety-related fault (in general). P-Head or TOW system loss can be detected in this way, and it is followed by warnings or advisories.

Learning Step/Activity 4: Identify Mission Checklists and Readiness Tests

• Pre-Mission Checklist: The pre-mission checklist is an automated checklist that is used to verify the correct status and readiness of the vehicle before any mission.
• Readiness Test: The readiness test is an automated sequence that confirms the integrity of selected vehicle functions.
• Accessing Mission Checklists: The maintainer can access Pre-Mission, During-Mission, or Post-Mission Checklists from the Vehicle's software.
• Readiness Test Setup Screen: This displays the tasks to be performed and ensures the vehicle meets readiness conditions.

Learning Step/Activity 5: M2A3 VDMS Architecture

• VDMS Architecture: The Vehicle Diagnostic Management System (VDMS) utilizes built-in tests (BITs) within various LRUs and software inside the TPU. These include startup BIT (SBIT), non-interactive BIT (NBIT), background BIT (BBIT), interactive BIT (IBIT), and Fault Isolation Test (FIT).
• Fault Isolation Test (FIT): This test is for maintenance use only, enabling the isolation of malfunctioning components.
• Accessing Vehicle Tests: The maintainer accesses the Vehicle Tests Menu through the maintenance/diagnostics section to conduct tests.
• Identifying and Verifying Faults: A maintainer should be able to record and identify faults before a maintenance action or repair begins.
• Accessing the Malfunction Advisory List: The maintenance can access the Malfunction Advisory List from the Vehicle Fault Summary menu.