Competition: Tank Design 2239

[Toxn]

5 hours ago, LostCosmonaut said:

@Toxn You mind if I steal your 80mm gun as an alternative armament for my vehicle? (I'm not actually in the contest, I'm just modeling tanks for the fun of it).

Go for it.

[N-L-M]

Judges, am I correct in assuming that small details like headlights, radio antennae, and tow hooks need not be modelled? 

[Sturgeon]

28 minutes ago, N-L-M said:

Judges, am I correct in assuming that small details like headlights, radio antennae, and tow hooks need not be modelled? 

 

It's never been a requirement before.

[LoooSeR]

1 hour ago, N-L-M said:

Judges, am I correct in assuming that small details like headlights, radio antennae, and tow hooks need not be modelled? 

I don't really care about those things.

[Sturgeon]

Pretty much done with the light tank as well:

 

[Sturgeon]

A sudden mid-stream change of turrets, and our weight has ballooned significantly beyond the original 10 t goal:

 

In this configuration the Sandy weighs 19.9 t curb, 20.8 t gross.

[Jeeps_Guns_Tanks]

6 hours ago, LoooSeR said:

I don't really care about those things.

 

While I commend the effort, I'm sure all the judges are fine with basic shapes with specs, the eye candy is very nice though! 

[Sturgeon]

HAH HAH HAH HAH

 

[Belesarius]

3 hours ago, Sturgeon said:

HAH HAH HAH HAH

 

Could that fire without doing a backflip?

 

[LoooSeR]

6 hours ago, Sturgeon said:

HAH HAH HAH HAH

 

1/3 of the tank is missing, Sturg. 

[Lord_James]

New, C3 L/50 Cannon, and mount: 

 

Spoiler

 

I managed to keep the width (420mm) as the previous C2, but this new mount is about 100mm longer and slightly taller. 

[Lord_James]

New turret to accommodate gun is practically done: 

 

Spoiler

 

20.8 tones, 1.97m high (currently), 8.81m long, 3.1m wide. 

 

 

Hull is getting revised, later. 

[Sturgeon]

This fucking light tank... Here's the Sandy Mk. 3:
 

 

The elliptical turret is much better protected... But also heavier. Weight is up to 22.6 tons gross, more than double what the Sandy was originally supposed to be. Since the original airdroppable concept seems unachievable now, I guess the Sandy is better suited as a tank for fighting Deseret? But I think the Donward can do that too, so I'm not sure there's much point to this anymore. The biggest problem the Sandy has right now is power: It was designed to fit an engine roughly equivalent to a Detroit 6V53T, which is a 275-310 hp engine or so, but at nearly 23t that isn't nearly enough power. I'm currently looking into flat engines that might work, hoping to cram at least 550 hp into the thing. If I can't do that, I'll have to make a totally new hull. Ugh.

Speaking of a bigger hull, I figured I'd see how this looked since le pancake turret is pretty well armored:

 

It looks... Special. Doesn't seem to be much merit to it, either, since it's nearly as heavy as the original turret version. This turret does have me interested in a low weight medium, though, something that would come out equivalent to a T-55.

[Toxn]

I checked a model of a BS3 against my turret and it turns out that a 100mm gun should fit just fine

 

Movement in the vertical is a bit limited though: -6 to +15 degrees. The weight should go up by about 2 tonnes if ammo count stays the same.

[Toxn]

On 8/16/2018 at 8:54 PM, Toxn said:

Primary entry, SPG and SPAAG to follow:

 

M8 “Elk”

 

 

Length: 6.6m (hull), 8.6m (total)

Width: 2.65m (hull), 3.25m (total)

Height: 2.7m

Weight: 40/21 t (empty weight)

Crew: 4 (commander, gunner, loader, driver)

 

Armour:

• 100/25mm (upper hull front)
• 100/25mm (lower hull front)
• 65/25mm (hull side forward)
• 25/15mm (hull side rear)
• 25/15mm (hull rear)
• 25/15mm (hull roof)
• 25/15mm (hull floor)
• 100/25mm (turret front)
• 100/15mm (turret side forward)
• 65/15mm (turret side rear)
• 25/15mm (turret rear)
• 100/25mm (mantlet)
• 25/15mm (turret roof)

 

Weapons:

• 80mm L/45 cannon:

               - APHE: 7.1kg, 820m/s, ~130mm RHA penetration (90’, 500m)

               - APCR: 4.3kg, 1045m/s, ~160mm RHA penetration (90’, 500m)

               - HEAT: 4.8kg, 500m/s, ~90mm RHA penetration (90’, any range)

               - HE: 6.1 kg, 500m/s

• Browning M2 heavy machine gun (turret roof)
• M240 machine gun (coaxial)

 

Engine: 18L, 450 HP (340 kW) V8 petrol engine (Ford GAA derivative)

Power/weight: 7.6 kW/t or 13.6 kW/t tonne

Max speed (road): 45km/h or 60km/h

Max sustained speed (offroad): 30km/h or 40km/h

Range: 300km/550km

 

 

Description

 

The M8 “Elk” was the result of a proactive design process intended to provide a ‘universal’ tank optimised for fighting a defensive war against Californian forces and serving in a more mobile role in the Oregon/Idaho sector. The design is also intended to have reserve capacity for upgrades as they become available.

The core of the vehicle is a simple hull with a clean, sloped front and a large engine bay in the rear separated from the crew compartment by a 25mm or 15mm (depending on the version) armoured bulkhead. The armour layout emphasises frontal engagements and crew protection, with the forward side armour (covering the crew compartment) being significantly thicker then the rear side armour.

 

The M8 is offered in two variants: a 45t ‘medium’ version and a 25t ‘light’ version. The medium version is designed to resist current-generation heavy anti-tank weapons across the hull front and turret frontal arc from any distance, with current generation medium anti-tank weapons being resisted across a 45 degree arc covering the crew compartment. The medium is expected to remain well protected against medium anti-tank weapons for the foreseeable future, and is expected to resist heavy anti-tank weapons across the hull front and turret front at ranges beyond 1000m. The light version sacrifices nearly all of its armour in favour of lower weight, retaining only 25mm plate to cover the frontal arc and crew compartment. This is, however, expected to provide protection against 20 and 30mm Deseret weapons at combat ranges. Some of this lightening is achieved through the use of aluminium components (most notably the road wheels) where possible. Although much less well protected than its medium cousin, the light version gains very good cross-country mobility and greater range. It also retains the excellent 80mm gun used by the medium, which is expected to remain effective against light and medium vehicles for the foreseeable future. The hull and turret are both of welded constuction, with castings only being used for a few components (most notably the gun mount and mantlet).

 

The engine bay is designed to facilitate service and repair, and has large rear doors for access to the engine and transmission. The engine and transmission, in turn, are mounted using a rail system so that they can be easily pulled. The radiators and fans are mounted in hinged doors on the hull roof, which also double as access points for service. The emphasis on ease of maintenance continues to the suspension system, which is a widened derivative of the historical HVSS designs used on the pre-war Sherman series of tanks. Each suspension unit mounts to hardpoints which protrude a bit below the hull proper, resulting in a very respectable 50cm of ground clearance. Due to the forward-heavy nature of the tank, the suspension units on the medium model are not evenly spaced. Instead the middle unit is positioned somewhat closer to the front unit than the rear unit. The engine, a 450-500 HP design based on the pre-war Ford GAA, drives vehicle through a rear sprocket. The medium and light versions use different transmission designs; with the medium’s being a more robust mechanical unit with a lower gear ratio, while the light uses a hydromatic unit based on that of the M24. Both vehicles are equipped with multiple reverse gears to facilitate shoot-and-reposition tactics.

 

The turret is roomy thanks to a large 1.8m turret ring, which is also expected to facilitate upgrade programs going forwards. It’s shape is six-sided, somewhat sloped, and contains generously-sized hatches for the crew. The turret is equipped with a full basket. The commander’s hatch is equipped with multiple vision blocks to provide good visibility while buttoned up. The commander and gunner also have access to periscopes (based on the M10 design) for the purposes of target acquisition and rough lay-in. The gunner’s periscope is selectable for 3X and 6X magnification, and has various reticles for the main ammunition types. A telescopic sight, based on the M70-series sights, is provided for fine lay-in. An azimuth indicator and gunner’s quadrant is provided for ranged fire missions. The rear of the turret houses the radio set – a new transistor design based on the pre-war SCR-500 series. This set includes an intercom system, and is expected to be less maintenance-intensive than our existing sets. The rear side sponson contains a small telephone, linked to the intercom system, to allow infantry to communicate with the crew.

 

The 80mm main gun has merely average elevation and depression: +37 to -8 degrees. This is something of a flaw, and may need to be corrected on future models of the vehicle. The turret drive is electric, and manages a full rotation in around 15 seconds. The electric unit does not allow for very precise movement of the turret at present, so the gunner’s handwheel is necessary for fine adjustment. In terms of power, the main gun is able to penetrate any commonly-encountered armoured vehicle from the front at combat ranges using the present APHE and APCR shells. It is expected to remain viable against most light and medium vehicles for the foreseeable future. The gun also sports a very good HE shell, which is fired using a low-velocity charge. The coaxial M240 machine gun provides a reliable level of firepower for anti-infantry work, while the roof-mounted M2 heavy machine gun provides a useful level of auxiliary firepower against soft-skinned vehicles, as well as a rudimentary anti-aircraft capability.

 

Overall the M8 offers good firepower, good protection (in the medium variant, at least) and decent mobility. It also offers a platform with significant margin for further development.

 

Acknowledgements

• Jeeps (the Sherman site is freaking goldmine)
• Various Sketchup users (especially Sketchy@Best, Stefan F., M L. and zdanwoj)
• Whoever came up with that Tank Designer spreadsheet that Sturgeon posted

 

Edit: I'm going to ask the Judges to use their imagination in regard to towing eyelets and radio aerials. Because I completely forgot to put those in.

XM8A1

 

 

Length: 6.6m (hull), 10.5m (total)

Width: 2.65m (hull), 3.25m (total)

Height: 2.7m

Weight: 43t (combat weight)

Crew: 4 (commander, gunner, loader, driver)

 

Armour:

• 100mm (upper hull front)
• 100mm (lower hull front)
• 65mm (hull side forward)
• 25mm (hull side rear)
• 25mm (hull rear)
• 25mm (hull roof)
• 25mm (hull floor)
• 100mm (turret front)
• 100mm (turret side forward)
• 65mm (turret side rear)
• 25mm (turret rear)
• 100mm (mantlet)
• 25mm (turret roof)

 

Weapons:

• 100mm L/53 cannon:

               - APHE: 15.8kg, 900m/s, ~210mm RHA penetration (90’, 500m)

               - HE: 15.6 kg, 900m/s

               - Vertical movement: -6/+15 degrees

• Browning M2 heavy machine gun (turret roof)
• M240 machine gun (coaxial)

 

Engine: 18L, 450 HP (340 kW) V8 petrol engine (Ford GAA derivative)

Power/weight: 10.7 kW/t tonne

Max speed (road): 45km/h

Max sustained speed (offroad): 30km/h

Range: 300km

 

Description

 

The M8A1 is an upgraded variant of the M8 medium design, incorporating a more powerful 100mm gun. This configuration sacrifices some mobility and crew comfort for hitting power, and is expected to allow the design to remain capable against all common armoured vehicles for the foreseeable future. The APDS round presently being developed for this gun, for instance, is expected to provide around 290mm of penetration at battle ranges. This, along with newer HEAT rounds and, eventually, APFSDS rounds, will also ensure that this design will remain competitive against MBT analogues if/when they emerge.

 

[Sturgeon]

HAH HAH HAH YES ARMS RACE AAAAAARMS RAAAAAAACE

[Toxn]

15 minutes ago, Sturgeon said:

HAH HAH HAH YES ARMS RACE AAAAAARMS RAAAAAAACE

Considering I only have one right now...

[Toxn]

My 120mm tank destroyer is going to look a tad redundant, though, if the 100mm version of my tank is selected.

[Oedipus Wreckx-n-Effect]

If I am ever asked for the definition of "scope creep", I will link to this thread.

[Toxn]

So I got curious as to why my calculations showed that my tank was 40 tonnes when the T-55 is 35 tonnes. Once you put them next to each other the answer becomes clear:

 

The model I used:

https://3dwarehouse.sketchup.com/model/80e27b6f-8cce-4f50-b22e-01790154b1c0/T-55

It needed to be re-scaled, but was otherwise in proportion.

[Bronezhilet]

Looks like a Panther: +5 tons

[Toxn]

10 minutes ago, Bronezhilet said:

Looks like a Panther: +5 tons

More like +10

[Sturgeon]

I'm confused, isn't it lighter?

[Toxn]

2 minutes ago, Sturgeon said:

I'm confused, isn't it lighter?

Mine is a bit over 40 tonnes, so no.

 

Edit: actual panthers are over 45 tonnes, so at least I'm not failing that hard.

[Sturgeon]

2 minutes ago, Toxn said:

Mine is a bit over 40 tonnes, so no.

 

Edit: actual panthers are over 45 tonnes, so at least I'm not failing that hard.

 

Right so wouldn't your tank be sort of a Panther minus 5 tonnes?