Detailed Study Artillery Flashcards
Abbreviations
ASPEFCS
MACS
INS
TTM
GNC
CAS
IMU
DHB
PCU
EPIAFS
MC
SAASM
FSA
AJM
AJ CCA
SES
BIP
AFATDS
Australian Portable Electronic Fire Control System
Modular Artillery Charge System
Inertial Navigation System
Tactical/Telemetry Module
Guidance, Navigation, and Control section
Control Actuator System
Inertial Measurement Unit
Data Hold Battery
Power Conditioning Unit
Electronic Portable Inductive Artillery Fuze Setter
Mission Control
Selective Availability Anti-Spoofing Module
FSA Safe and Arm
Anti Jam Module
Anti Jam Circuit Card Assembly
Second Environment Sensor
Ballistic Impact Point
Advanced Field Artillery Tactical Data System
XM982 Main Fill and Booster
Main Charge
5530g PBXN-9
Booster
55g PBXN-9
XM982 three main sections
a.Guidance, Navigation and Control (GNC) Section;
b.Payload Section; and
c.Base Assembly Section.
Two variants of XM982
XM982-Tactical and the XM982-Tactical/Telemetry (TTM) - TTM not in ADF service. Identifiable by black band just aft of radome.
The XM982 CAS control software communicates with the MC using one of five command messages. The five commands are:
a. Canard Position Command;
b. Built-in-Test (BIT) Command;
c. Battery Activation Command;
d. Canard Deploy Command; and
e. Reset CAS Command (Debug/Factory Usage Only).
Two lithium thermal batteries in CAS:
a. Electronics Battery. The 9.5 to 16 VDC electronics battery provides a minimum of 270 seconds of unregulated (internal) power to the PCU and FSA logic circuit while the setback/acceleration associated with firing activates the electronics battery. The electronics battery provides the power to fire a squib in order to activate the 28 VDC Actuator Battery, when commanded by the MC, via the CAS control software.
b. Actuator Battery. The 28 to 50 VDC actuator battery provides a minimum of 245 seconds of unregulated (internal) power to the canard motors and FSA arming circuit. The electronics battery provides the power to fire a squib that activates the actuator battery approximately one second before canard deployment. To fire the squib, the MC sends a CAS command word (Battery Activation) to the CAS. Once validated, the CAS control software asserts two discrete signals, each of 20 millisecond durations. Once battery activation is commanded, the CAS control software disables further battery activation command processing.
Two arming environments for the XM982 FSA arming
The first arming environment is the setback and rotation which accompanies firing. Setback mechanically unlocks the FSA whilst rotation provides the energy to wind a torsion spring that later drives the rotor assembly into the armed position.
The second arming environment is the XM982 spin rate decay that accompanies canard deployment. The SES detects the spin rate of the XM982 before canard deployment and then the post transition to roll-stabilisation spin rate following canard deployment. This second environment must be detected in order for the FSA to arm. If the second arming environment is not detected the FSA will enter the fail-safe mode.
The XM982 FSA has three selectable set-modes:
Proximity (Airburst)
Point Detonating (PD) and
PD delay
Each is set during initialisation. The FSA firing capacitor sends a firing pulse that activates the explosive train (M84 Detonator, PA 509 Lead and Booster) to detonate the warhead. In PD mode, the FSA activates the explosive train immediately. In Proximity (Airburst) mode, it initiates the explosive train within 500 microseconds of receipt of the correct HOB Sensor Signal. In PD delay mode, it initiates the explosive train within 8.5 ±0.5 milliseconds after impact.
The XM982 base assembly contains:
a. inert base bleed and inert igniter;
b. bearing assembly with Roll Component Clutch (RCC);
c. eight curved fins;
d. slipping driving band; and
e. Base Hood.
XM982 OPERATION
Initialized for guided flight through inductive coil interface with EPIAFS. Initial GPS data, fuzing information, mission planning data held in MC. 1st activation of the XM982, audible sound from DHB. Mission data kept for 7 mins. Failure to fire XM982 in 7mins will zeroise GPS data, fuze settings and mission planning data. System reset max of 20 times in 48hrs fm 1st activation.
Slipping driving band w/ base rotates independent from XM982, less spin. XM982 exits muzzle - base hood removed from pressure differential between barrel free air - stabilisation fins deploy. Spinning base and deployed fins = stability and range. Canards give directional control.
After firing, MC conducts BITs and confirms loading of GPS keys, GPS data, valid mission data and satellite acquisition just before apex of flight. Also confirms four canards deploy. Failure of critical BIT, or unable to acquire satellite will fail-safe XM982 - continues unguided to Ballistic Impact Point.
No fail-safe - MC commands CAS ‘activate’ actuator battery 1.25 secs after ‘activate’ COMD, CAS tells MC actuator battery minimum required voltage reached, at the correct time, MC commands CAS to deploy canards. Fail-safe mode MC stops communicating with CAS and all other sub-systems. In TTM MC continues sending telemetry data.
If prox(airburst), MC powers HOB sensor 3.5 secs before impact.
3 secs to target FSA ordered to ‘arm’ if previous three consecutive estimated distances less than miss distance threshold and nav uncertainty is less than threshold determined in tests. FSA locks removed and piston actuator fires, aligning firing chain for arm. Failure of distance tests will fail-safe XM982 and not function on impact
.
If prox setting, MC commands FSA final firing using HOB sensor. When PD or PD delay, firing initiated via PD switch in FSA itself.
XM982 warnings
The XM982 is not to be fired in temperatures below -40°C (-40°F).
The XM982 is not to be fired in head winds that exceed 105km/h due to the potential for the wind to project the Base Hood and/or slip obturator behind the weapon and cause death/injury.
The XM982 is not to be loaded into a hot-gun (greater than +176°C)
The XM982 is to remain in its BAM PA179 container until immediately before it is required for use.
An XM982 that has been loaded and is subsequently removed from the gun for any reason is to be sentenced unserviceable.
In temperatures below 0˚C (+32˚F) the XM982 is required to be set with the EPIAFS twice, with a period of 30 seconds between the first and second setting actions, to ensure data hold battery functionality.
M795 fill and body
36kg high fragmentation steel forged body
Main charge
10.80kg TNT
0.136kg supplementary charge
List 155 natures
HE M107
HE M795
TRG M1122
ILLUME M485A2
WP M825A1
XM982
Control Actuator System components
Canards,
an electro explosive device (EED) to deploy the canards,
actuator motors,
electronic circuit cards,
the Electronics Battery,
the Actuator Battery
the IMU.
The GNU contains:
Radome
Height of Burst (HOB) sensor
GPS antennas (2 x identical)
Guidance and Navigation Unit shell
Data Hold Battery (DHB)
Mission Computer (MC)
GPS receiver (tracks ≤ 12 satts)
Power Conditioning Unit (PCU)
Telemetry Module
Tactical Telemetry Antenna
Anti-Jam Module
What is the unit load of XM982 and its composition?
One in every nine XM982 projectiles, and hence one projectile in each DA39 Unit Load of XM982 projectiles, is a TTM variant.
Difference between M762A1 and M767A1?
Fuzes are identical except M767A1 incorporates a booster charge of 30g PBXN 5 type 1
