Jump to content
Sturgeon's House

Leaderboard

Popular Content

Showing content with the highest reputation on 06/14/2021 in all areas

  1. Not sure when these photos were taken but ROK BMP-3s doing a river crossing exercise
    2 points
  2. FFG has handed its HiMoLap technology demonstrator to the BAAINBw (which had ordered it). https://esut.de/2021/06/meldungen/27866/demonstrator-mobile-landplattform/
    1 point
  3. Serge

    French flair

    Once more, we are forwarding in a strange direction. https://www.janes.com/defence-news/news-detail/texelis-and-cnim-team-for-new-engineer-vehicle
    1 point
  4. Toxn

    Competition Suggestions

    Mini-competition suggestions, for consideration some time next year: 1. Design an AT gun (2239) In this mini-competition, contestants would be asked to design a conventional, WW2-era AT gun for use by one of the post-apocalyptic US polities. The gun would be designed with an understanding of how weapon and armour technology would be likely to develop, and should include a description of the gun itself, its mounting and its ammunition. 2. Design a ATGM (2247) In this mini-competition, contestants would be asked to design an ATGM for use by the Texans, in a project running parallel to their first forays into MBT building. The contestants would have to simulate the overall configuration and aerodynamics of the ATGMs using OpenRocket, and would have to provide a coherent explanation for the warhead layout and control scheme. Submissions would be in the form of ORK files and a brief description. 3. "Fix a tank" 2 - France, 1946 The second "fix a tank" competition, this time to try and fix the problems that the French had with their post-war Panthers. The contestants would not be allowed to radically re-design the vehicles (or, at least, would have to provide better and better justifications for each new change), but would try to work with what they had to fix as many issues as possible. The goal would be to produce a vehicle that the historical 501st and 503rd armoured regiments could operate into the 1950s. 4. "Fill in the blanks" - design the Californian heavy from the first (2239) competition The Californian heavy tank (which was very obviously an expy of the WW2-era Tiger) was the vehicle which kicked off the entire arms race that has become the dominant narrative of the post-apocalyptic competitions. A cryptic beast, it was described as weighing 50mt, having 76mm of armour and being armed with an 89mm gun that can penetrate ~140mm of RHA at 1000m. This competition would involve contestants filling in the blanks to create a tank that fits these criteria (ie: not inventing a vehicle with a better gun, massively thick armour etc). The submissions would be done using a formula approach (for which, see here) with the contestants being asked only to model the hull/turret armour layout in detail (ie: in terms of mass). Everything else (the gun, ammunition, suspension, engine, optics etc.) can be simply a visual representation with standard weights being applied for variable-weight components. The submission would be in the form of drawings (front, side, top view) and a description to follow a standard format.
    1 point
  5. Dunno if that has been posted here before, but the YouTube algorithm has struck again. The APFSDS model wasn't specified, only that it is a 120mm sabot. The failure seen here apparently stems from a destruction of the fin assembly, which also resulted in tip detachment from the long rod's main section.
    1 point
  6. Some details of the evolution of the In-arm suspension unit for the Redback. Some of the ride-height adjustments available: The evolution over time: The K21 cutaway: The Redback evolution:
    1 point
  7. Main Battle Tank, 2247, project names "Derebus" and "Derebus-M" Manufacturer: Manufactuer: Paramount-Allen-Fullerton (Para-allful) Conglomerated Table of basic statistics: Note: all statistics provided are for Derebus unless otherwise noted. Parameter Value Mass, combat Armour mass: (1-2" (25-50mm) RHA base plus ERA, composites, side skirts and engine bay liner): 20.6t (18.5mt) 43.1t (39.1mt) modelled, 43.4t (39.4mt) calculated Length, combat (transport) 246" (6.25m) hull, 379" (9.63m) total Width, combat (transport) 150" (3.8m) with skirt Height, combat (transport) 95" (2.41m) to top of commander's hatch, 109" (2.77m) total Ground Pressure, zero penetration Ground pressure (calculated MMP): 29.4 PSI (203 KPa). Nominal ground pressure (based on calculated weight): 10.3 PSI (70.77 KPa) Estimated Speed 37 mph (60km/h) Estimated range 490 mi at 30 mph Crew, number (roles) 4 (commander, gunner, loader, driver) Main armament, caliber (ammo count ready/stowed) 5-inch 55 calibre (127mm L/55) high/low pressure gun, (19 charges, 9 active projectiles, 10 inert projectiles in turret/ 16 charges, 8 active projectiles, 8 inert projectiles in hull) Secondary armament, caliber (ammo count ready/stowed) 3 x .30 cal MG (600 rnd belted each ready/ 1200 rnd belted each stowed) Vehicle designer’s notes: The Derebus family of vehicles (provisionally named Derebus and Derebus-M) are intended to fulfil a procurement strategy emphasizing mobility (tactical, operational and strategic), reliability and superb value for money, achieved using a lightweight vehicle design, proven automotive components and a high/low capability mix. Derebus sports a state-of-the-art fire control system allied to a powerful 5" gun, while Derebus-M provides supporting firepower and a larger ammunition load thanks to it's 4" gun. Both vehicles provide superb protection across their frontal arcs, with the Derebus making use of cutting-edge composites to save weight. Both Derebus and Derebus M are immediately available to fulfil all of your defense needs. Vehicle feature list: Mobility: 1. Link to Appendix 1 2. Engine- V-12 Diesel (Kharkiv V-2-55 derivative), 2441 ci (40l) displacement, 600HP (448kW), liquid-cooled. Note: alternate engine and transmission arrangements are provided for in Appendix 3 3. Transmission - hydraulic torque converter feeding into Merritt-Brown-style double differential system, 7 forward/1 reverse gears. 4. Fuel - diesel, ~2400lb total (639lb/290kg in tanks flanking the driver, 1764lb/800kg in rear sponson tanks, estimated range of 490mi at 30mph. 5. Engine, transmission and cooling are arranged in removable aluminium tub housed in engine bay. The tub is removable by sliding out the rear of the bay. 6. Suspension - torsion bar, variable travel (presently 11.8" (30cm)), 20" (0.5m) ground clearance, geared torsion bar suspension, each axle pair in detachable units shrouded by aluminium housings. Wheels are 23.6" (0.6m) in diameter, with a track width of 27.6" (0.7m) and a pitch of 7.7" (0.195m). Survivability: 1. Link to Appendix 1 2. Link to Appendix 2 3. Non-specified survivability features and other neat tricks - highly sloped turret and hull front (75 degrees), charges and active ammunition (HEAT-FS and HE) arranged in sealed tubes leading to a blast chimney that outlets to blow-off panels in the turret roof, turret sides, hull roof and hull sides. A. Weapons: 1. Link to Appendix 1 2. Main Weapon- a. Type: smoothbore, vertically trainable +15/-10 degrees b. Caliber: 5"/127mm c. ammunition types and performance: Note: the armour used for the target has the same hardness (360BRN) as the armour used in the vehicle. The target was at 0 degree obliquity for calculation purposes. HEAT-FS (low-pressure setting): 46lb (20.85kg), penetration of around 21" (535mm), 3074fps (937m/s). HE (low-pressure setting): 46lb (23.2kg), 201oz (5.7kg) fill, estimated blast penetration of ~55mm RHA, 2910fps (887m/s) APFSDS (high-pressure setting): 15:1 LD, 550BHN monosteel body, tungsten insert, 115mm cap, ring sabot, 1800m/s, 15.7/13.8" (400/350mm) penetration at 100/2000y (lower estimate, 17.1" (435mm) at 2000y upper estimate). d. Ammo stowage arrangement - 19 charges, 9 active projectiles, 10 inert projectiles in turret; 16 charges, 8 active projectiles, 8 inert projectiles in hull. e. FCS: Duel axis stabilized main gun Semi-autoloader: the loader places the charge and warhead on trays in the bustle. these are then fed into the gun using an automatic mechanism (horizontal rammer, pivoting loading tray and rigid chain actuator to ram the warhead and charge home). The gun automatically returns to the loading position after each shot. A short spring at the end of the actuator helps to smooth out the loading impulse. f. Neat features: Gun has a high-pressure and low-pressure recoil option, selectable on the slide – this doesn’t affect the recoil mechanism, it just changes where the trip key is to unlock the breech (warning: don’t fire high-pressure ammo with the low-pressure setting selected!) Gun uses a separate 6.9x27" (175x685mm) charge: 44lb/20kg mass, semi-combustible case built along the lines of the 4Zh-40 charge used with the historical 125mm 2A26 gun), matching the length of the HEAT-FS round. The charge gives space to produce a more powerful round to match higher future barrel higher pressures (when using a secondary charge with the APFSDS projectile itself). 74000 PSI (510 MPa) gives a potential power of 15MJ. 94000PSI (650 MPa) gives a potential power of 19MJ. Final penetration potential of the gun with early monobloc DU projectiles is something in the region of 22" (550mm) at 2000y (putting it on par with Mango and Vant). Being able to store and handle a longer projectile (ie: above 27") would probably allow something a bit better than Snivets. Low-pressure charges are shortened (17.1" / 435mm) and come with an ejection spring to work with the same storage tubes as the high-pressure charges. 3. Secondary weapons - 3 x .30 cal MG, 1 coaxial, 2 in mountings attached to the commander and loader's turret hatch 4. Link to Appendix 3. B. Optics: 1. Primary gunsight: single axis stabilized gunner’s sight 2. Secondary gunsight: vertical coincidence rangefinder (stadiametric, 39.4" (1m) base), doubles as a redundant back-up sight. 3. Miscellaneous optics: Commander and loader's rotating hatches, including vertically trainable (+/- 15 degrees) periscope in front of hatch, degree markings on hatch ring to allow rough direction of gunner to target. Driver's periscope, vertically trainable +/- 15 degrees C. FCS: 1. List of component systems, their purpose and the basic system architecture: Simple electronic gun-follows sight fire control system (encoder connected to sight mirror feeds elevation data into a transistor-based PID controller, which tries to match position on a similar encoder connected to the gun. When gun position and sight position align, the firing mechanism is electronically triggered). LRF mounted above barrel, solid-state components, maximum operating range of 5km in clear conditions, average estimation error of 1%. Uses flashlamp-pumped ruby laser, optical sensor, quartz timing circuit and the sequential event time sampling approach (with post-sampling amplification) to allow time-of-flight rangefinding using a lower timebase and bandwidth compatible with current electronics. 2. Link to Appendix 3. Fightability: 1. List vehicle features which improve its fightability and useability: Engine bay approach simplifies engine and transmission replacement via rear bay doors. Generous rear hull roof hatches simplify servicing and maintenance. Bolt-on suspension units simplify field replacement and repair. Commander and loader's hatch design improves buttoned-up visibility Additonal Features: See Appendix 3 Free expression zone: "...bellicis"
    1 point
  8. FINAL SUBMISSION: XG-48E3 Comanche Battle-cruiser Table of basic statistics: Parameter Value Mass, combat (armor) 124,450 lbs (59,950 lbs armor) Length, combat (transport) 31.7 ft (25.6 ft) Width, combat (transport) 12.1 ft (12.0 ft) Height, combat (transport) 8.8 ft (8.3 ft) Ground Pressure, zero penetration 1,795 psf Estimated Speed 50 mph Estimated range 500 mi Crew, number (roles) 4 (Commander, Gunner, Loader, Driver) Main armament, caliber (ammo count ready/stowed) 40 rds 5in/24 (33 in turret bustle rack, 7 in ready rack) Secondary armament, caliber (ammo count ready/stowed) 1,200 rds .50 caliber, 10,000 rds .30 caliber, 3,000 rds .40 cal ammunition Vehicle designer's notes: The XG-48E3 Comanche is a Battle-cruiser-class heavy tracked truck ("tank") with powerful armament, resilient armor, and a high degree of mobility and range. Comanche was designed around a "fightability philosophy" in which tanks are seen as an extension of the fighting man and must permit as much as possible the operators to conduct their mission without interference. Comanche sports a powerful 5in-24 XG-47E5 cannon firing armor-piercing flechette (APF), high explosive anti-truck (HEAT), and high explosive (HE) rounds. Comanche's armor is resistant to next-generation flechette rounds likely under development by near-peer adversary states like California and Cascadia. Comanche is provided with a generous 1,200 horsepower motor which gives it a power to weight ratio of 19.4 hp/t, well in excess of requirements. Comanche is built to be upgraded, and can be augmented with a variety of improved armor, gun, engine, and fire control packages as needed. Vehicle feature list: Mobility: 1. Link to Appendix 1 - RFP spreadsheet, colored to reflect achieved performance. 2. Engine- Carrolton AER V-12 diesel, 2,850 cu in, 1,200 hp, liquid cooled. (Comparable to MB MTU 873) 3. Transmission - Hydromechanical power shift, reversing and steering fully and semiautomatic transmission with four forward and four reverse gears, mounted directly to the engine via integral torque converter. (Comparable to HSWL 354) 4. Fuel - Diesel, 482 gallons in two tanks alongside driver in front, 145 gallons in two tanks below engine in rear; 683 miles range. 5. Sand scrubbers, filters, cleaners, blowers, etc. Powerpack can be removed from rear with crane. 6. Suspension - Independent externally dual-coil sprung single-wheel bogies, 7 per side, 14 inches wheel travel from neutral, 8 inches extension (22 inches total travel), 18.2 inches ground clearance. Survivability: 1. Link to Appendix 1 - RFP spreadsheet, colored to reflect achieved performance. 2. Link to Appendix 2 - armor array details. 3. Protection for Comanche is rated for 13 inches (3BM6+) throughout the +20/-20 degree frontal arc with very minimal weakspots (slits, etc) only. At any place on the tank 90 degrees to the side, it will repel the Mormon 6" HEAT weapon. Coincidentally, as a byproduct of a weight-saving and turret-balancing measure, the turret will also repel the 6" HEAT weapon from the rear. Roof is rated for plunging fire. Bottom armor is rated at 1.25" RHAe vs mines and blast. As qualified tankers are in short supply in the Lone Free State, great consideration was given to crew safety, and the ability for crew to swiftly evacuate a damaged tank if necessary. Ammunition is stored in a separate compartment in the turret, and if hit, two large blowoff panels will vent the pressure from that compartment before that pressure can damage the firewall to the crew compartment. Two large hatches are provided for the commander, gunner, and loader (the commander and gunner share a hatch), both of which are fully spring-assisted and easy to open. The driver is provided with a generous hatch which is heavily armored, and is also considerably spring assisted. It tilts, and then rotates away for easy egress. The driver can egress the vehicle with the turret in any position. The driver is also protected by two large tanks of diesel fuel with a capacity of 241 gallons each. These tanks cover the entirety of the driver to each side, giving him considerable additional protection. Image of the XG-48E3 Comanche with the outer armor panels made transparent, showing the sophisticated NERA arrays. Firepower: A. Weapons: 1. Link to Appendix 1 - RFP spreadsheet, colored to reflect achieved performance. 2. Main Weapon- a. XG-47E5 autofrettaged smoothbore load-assisted cannon with horizontally-sliding breech b. 5in/24 L/45 c. XG-147J 15:1 L:D Armor Piercing Flechette, 530mm+ RHA penetration at 2,000 yd, XG-147H High Explosive Anti-Truck, d. 40 rds (33 in turret bustle rack, 7 in ready rack) e. FCS - relevant systems, relevant sights for operating the weapon and so on. f. Neat features. 3. Coaxial armament consists of 1x .30 caliber G-17A5T machine gun and 1x .50 caliber G-19A2T machine gun, which are slaved to the main gun. Independent armament consists of 1 additional G-17A5 and 1 additional G-19A2 machine gun, and 2 dual close-in .40 caliber G-346E1 machine guns. Ammunition stowage is 1,200 rounds of .50 caliber ammunition, 10,000 rounds of .30 caliber ammunition, and 6,000 rounds of .40 caliber ammunition. 4. Link to Appendix 3 B. Optics: 1. The gunner is provided with a fully stabilized 2.5-21x disturbed reticle main gunsight equipped with a laser range-finder and engageable night vision system. A simple lens with a stadia reticle is provided, which can be engaged if other systems fail. The reticle on the primary optic automatically adjusts for the selected ammunition type, and for expected wind drift and drop at range. No further sight adjustment is required once the gunner has lased the target, he simply puts the dot on the target and fires. 2. Due to the advanced nature of the laser range-finding system, a backup optical range-finder system is provided mounted to the roof of the XG-47E3's turret. This system triangulates the distance from the target in a manner similar to human depth perception, but many times more precise. It is also fully stabilized. C. FCS: 1. The commander is provided with a 360-degree vision cupola with eight all around periscopes which allow him to detect targets at any angle from the vehicle. These periscopes are also night-vision compatible. He is also provided with his Commander's Independent Gun Sight (CIGS) which is a 360-degree rotatable gun-sight that allows him to lase and engage targets at any distance. He is provided with the capability to automatically slave the rest of the turret to the target lased with the CIGSs, which gives the Comanche the ability to rapidly engage targets even in different locations requiring considerable rotation of the turret. 2. Link to Appendix 3 Fightability: 1. According to the "fightability philosophy", Comanche's fighting space was developed first, before any armor arrays were laid out or any turret weldment drawings created. Instead, the Ordnance Authority's 5in-24 gun, ammunition, ammo rack, and all the internal systems, controls, and all other things in the turret were mocked up out of cardboard, toilet paper tubes, and paper mache, and placed around a working test crew of G-12 drivers from Albuquerque. Special care was taken to listen to this crew and to incorporate this feedback into the layout and design of the tank. For instance, although Comanche is designed to operate normally with a loader, the loader's job is so reduced (at their request!) that it is entirely possible for the tank commander to perform all loading functions with minimal distraction and reduction in rate of fire. This is possible because all ammunition selection and ramming functions are automated, and because all of the loader's controls are placed within easy reach of both him and the commander. More details on this arrangement are given in Appendix 3. This arrangement was used to perform fightability experiments and once these were complete and conclusions about control and equipment placement were drawn, a cardboard shell was constructed around the compartment and fightability validation tests carried out. This resulted in an internal "shell" onto which outer armor arrays were built up. Additional Features: Automatic fire suppression system, individual wet ammunition storage, a water cooler, ramen boiler, it slices, it dices, it pulverizes! Other buzzwords! Free expression zone: In loving memory of former Head Designer Juan Taylor: He's not dead, he's just really unhappy.
    1 point
×
×
  • Create New...