DS - Mortar Flashcards
(45 cards)
What is the primary ignition cart used on 60mm mortars?
M702 Ignition Cart
What is the candle power for 60mm Illum M721?
Max 400 000 for 40secs
Min 250 000 for 32secs
What is the candle power for 60mm IR Illum M767?
500 an near IR wavelength of the electromagnetic part of the spectrum (between 60 to 90um)
How does the Fuze PD M775 work?
- Safety pin is removed.
- On acceleration, the setback pin moves rearward against a spring, releasing a slider, which holds the striker in its rearward position.
- Once the striker is released, it travels upward allowing the ball bearings to be forced into centrifugal alignment between the striker and the primer.
- On impact, the striker is driven into the ball bearings, which initiate the primer, igniting the pyrotechnic smoke cartridge. It produces a flash, audible sound and smoke to simulate HE
How does fuse MTSQ M776 work?
xx
The time is set using the fuse setter. The safety pin is removed before firing. When the round is fired and an acceleration of 500g is reached, the setback sleeve withdrawals, allowing setback pins to retract, unlatching the pallet of the escapement. The setback pins lower collars disengage, setting the spring-loaded detonator housing free to turn after the detonator housing locking shaft extension has turned out of the slot in the detonator housing. The barrel continues to turn until the gap in its crown aligns with the tongue of the firing lever. The striker bushing spring forces the bushing downwards and forces the firing lever and the release lever apart, disengaging the claws, striking the firing pin head and thrusting it into the detonator, this initiating the firing train at the pre set time.
What is the arming distance for the M783 MO fuse?
100m
What are the four settings for the M734A1?
Prox - 14ft
NSB - 7ft
Impact
Delay - 50-150ms
Label the 60mm IR Illum mortar.
Ignition cart M702 Fin M27 Propelling charge M204/M235 Base plate Illuminant First fire composition Time fuse M776
What is the augmenting charge used for the M0221A1?
AR2205 Single base x 6
What is the minimum safety arming distance for MTSQ M772?
40m
How does the 81mm Illum work?
Obturator ring expands under gas pressure from burning propellant causing forward obturation. The gases propel the mortar bomb. The setback force during firing unlocks the fuses setback safety device, commencing the arming sequence. When it reaches pre selected flight time, the fuse functions and initiates the booster. The internal pressure build up causes separation of the front and tail cone sections by fracturing the shear pins. The illuminating assembly is ejected rearwards from the front section of the mortar body. Simultaneously, the fuse booster initiates the ignition system of the illuminant canister. Deployment of the parachute controls the rate of descent.
How many wedges and what weight are in the 81mm Smk RP?
28 wedges
- 43g
What is in the 81mm Smk RP?
M752A1 Ignition Cart
M218 Propelling Charge
M819 Loading Assembly
What is the GAM for and what is its life expectancy?
Where are the Gas Absorbent Modules (GAMs) fitted?
xx
- The GAM is used to encapsulate phosphine gases (Red Phos by-products) .
- 7-10 year life expectancy
- one is located in the base of the fibreboard cylinder and the other is fitted to the tail-cone of the mortar cartridge forward of the M218 Propelling Charge Assemblies
What powers the MO M734?
What is the minimum arming distance
a turbine alternator
Minimum arming distance 100m
81mm IR M816 w MTSQ M772 Actions from Time Set
On achieving the pre-selected flight time, the fuze functions resulting in the initiation of the fuze booster. The internal pressure build up as a result of the function of the fuze booster causes separation of the front and tail cone sections of the mortar body by fracturing the shear pins.
On separation of the mortar body, the M816 IR Illuminating Assembly is ejected rearwards from the front section of the mortar body. Simultaneously, the function of the fuze booster initiates the ignition system of the IR illuminant canister.
Deployment of the parachute assembly controls the rate of descent of the IR illuminant canister.
The IR illuminant canister generates a minimum IR luminosity of 50 watts/steradian for a minimum period of 60 seconds.
Describe the parts of the Cart 81mm Illuminating M9769A2 Fzd MTSQ DM93?
Fuze, MTSQ DM93 Expulsion Charge Delay Element Illuminant ... Body, front Shear Pin Drogue Parachute Obturating Ring Body, rear Main parachute Augmenting Charge Tailfin Assembly Primary Carttridge
What is the selectable time range for the FZ MTSQ M776?
between 6 and 54 seconds in graduations of one second
What is the difference between DM93 MT
and DM93 MTSQ
- The DM93 MT has the SQ element removed
- There is a Deformation zone at the front of the steel nose cone.
What is the fuze fitted to which round
currently in service?
Cart 81 mm ILLUM M9769A2 xx??????
Fuze MTSQ DM93
What is the difference between DM93 MT and DM93 MTSQ
- The DM93 MT has the SQ element removed
- There is a Deformation zone at the front of the steel nose cone.
What are the 2 modes of function of the
Fuze MTSQ M772?
Mechanical Time and Superquick (PD)
What is the luminosity and burn time of the illuminant composition of the following 2 Illum bombs:
- CART 81MM Mortar IR ILLUM M816 Fzd MTSQ M772?
- Cartridge 81mm Illuminating M853A1 Fzd MTSQ M772
- IR Luminosity: 50 watts/steradian
Minimum of 60 secs - Luminosity: 525,000 Candela
Minimum of 50 secs
What is the minimum arming distance and time?
CART 81MM MORTAR IR ILLUM M816 FZD MTSQ M772
- delay of approx 1.0 seconds
- not less than 40 METRES
