THANK YOU GUYS

seems like my efforts were paid, only 2 days in and this become my most popular (more upvoted) post!

Here it is, as promised, a legendary FV4005, a true knight ready to protect its land and comrades on the battlefield, I present to you, the FV4005 “Lancelot”
First, I will show the basic for you to be able to command this absolute unit, the new specifications and the modifications this vehicle has compared to the original tank.

Controls:

AG1: Release the gun from the holder / Allow the movement of the turret (rotation) and the gun (elevation).
AG2: launch smoke grenades (All at once)
AG3 + VTOL (up): Open the door behind the turret and the turret hatches
AG4: Turn on the road lights
AG5 + VTOL: Turn on the spotlight and allows it horizontal movement
AG7: Turn on the IR spotlight and reticle illumination
Yaw (Q;E): Controls the turret (horizontal) movement.
Trim (arrows): Controls the Gun (vertical) movement.
Roll (A;D): Controls the tank (horizontal) movement.
Pitch (W;S): Controls the tank (forward/backward) movement.
Fire Weapons (Alt): Fire the Main Armament (Air/Ground) or launch the smoke grenades (1 by 1) (Ground)
Fire Guns (Space): Fire the coaxial machine gun.
Landing Gear (G): Control the recoil spade.
Cockpit View: Gunner View (reticle)
Cam 1: Driver View.
Cam 2: Commander View.

Specifications:

Dimensions
-Length: 7.82m (25’7") (without gun) / 10.94m (38’3") (with gun and extra fuel drum)
-Width: x 3.39m (11’1") / 4.02m (13’2") (with the bags)
-Height: 3.6m (11’8") (without antennas) / 4.31m (17’4") (with antennas)

Mobility

-Total weight: (129,9 Klbs) 64,9 US tons
-Engine Power: 650 hp
Power-to-Weight ratio: 10 hp/t
-Propulsion: Rolls-Royce Meteor; 5-speed Merrit-Brown Z51R Mk. F gearbox 650 hp (480 kW), later BL 60, 695 bhp
-Speed: Forward: 32 km/h (20 mph) / Backward: 8km/h (5mph)
-Fuel Capacity: 138 gal (552 L)

Armament

-Main: QF 183 mm (7.2 in) L4 Tank Gun (12 rounds)
-Shell type: High Explosive Squash Head (HESH)
-Reload time: 25 seconds.
-Guidance: vertical: +16º/ -6º horizontal: ±45º
-Secondary: Besa (15mm) coaxial machine gun (600 rounds)
-25 rounds-belt with 3 seconds of reload.

Armor and Survivability

-Armor: frontal hull armor: 120 mm / Turret: 14 mm all over + 30 mm frontal armor plates on the turret.
-Crew: 5 (driver, gunner, commander, x2 loaders)

Features:

-Realistic look
-Realistic dimensions
-Realistic gun specifications
-Realistic tracks and hull movement
-Realistic general specifications and other movements
-Working recoil spade, back turret door, gun holder, turret hatches, lights…
-Detailed turret interior

What is new?

-New details
-New controls
-New attachments
-New painting
-New parts
-Fixed minor bugs and wrong parts
-New specifications

Observations:

This is the biggest project I ever did here on SimplePlanes, my PC could barely support testing this 2500+ vehicle, even with the worst settings. So, there could (and probably will) be some bugs or somethings I did wrong and did not notice, if you notice something please tell me in the comments and I will see what I can do. In addition, I am not an expert in tanks or war history, so, if some details or attachments that I put in this build are wrong or do not make sense you can tell me too. Also, I know the “England flag” in the extra frontal armor plate seems more like a Nordic country like Norway, read the little history I made and you understand why.
Be a bit more cautious playing this tank, aim good before shooting, a 25s reload can be very boring. Also, when putting the gun back into the holder you have to align the cannon and the turret in the right place, to the cannon just press (left arrow) and it will go back to 0º of elevation, the turret have to be aligned manually, it isn’t hard, just a bit tricky the first time.
The Engine and tracks are not the best for climbing hills; actually, they are horrible for this. Therefore, if you want to play more dynamically you can easily change the tracks and cannon specifications in the garage, or you can download other version of this tank, like the light version with less part and better settings, like 5s reload, 200 rounds and 40km/h 1000hp engine, ideal for a fast gameplay:

light version FV4005 Stage II

Please, notice that the story below is fictional and do not meant to offend anybody. I do not know a lot of the history of the WWII so if anything seems unreal or improbable I am sorry.

FV4005 “Lancelot” History:

The invasion of the Normandy was a failure and the Nazis forces start gaining power again. With the invasion of new territories to 1945-1950 the Third Reich gain the precious resources the needed to produce they idealized and magnificent projects. On the ground there were now new and extremely strong enemies, like the Panzer VIII Maus, the Entwicklung Tanks Series, Massive railguns, advanced artillery and other threats.
To combat the new axis ground force the allies started to produce with fast speed its own new tanks. To be able to cause real damage to the super heavy German combat vehicles were needed very powerful and big guns, like the Ordnance Quick Firing 183 mm (7.2 in) L4 gun. At the time, it was the largest and most powerful tank gun in the world, one hit on the right place could take out an E-100 easily. With the intention to make this massive gun mobile, in 1950 the FV4005 project was created, the L4 was mounted on a Centurion Mk. III hull and enclosure in 90º traversing turret with 14mm of armor. With the possibility of the axis start to retake it invasions at the Norway and Sweden, the project was rapidly finished in secret and in 1952, the mass production of the FV4005 Stage II was approved.
The British guess was right, less than 6 month of the start of the mass production the Germany started to send ground force to Norway and Sweden to fully conquer it territories. With the help of the Soviet and Swedish army, the allies mounted an ambush to take the biggest group of the axis forces heading to Stockholm. With 5 infantry divisions and 1 armored division, the axis force would were with far advantage if only the expected Sweden and Soviet forces, who were already weakened, were waiting for them. But they weren’t counting with the presence of British’s , with only 1 infantry division and 1 armored battalion, but with its 25 brand new FV4005 tanks specialized in taking out German super heavy tanks.
A brutal conflict occurred, and the FV4005’s proved its efficiency. Although being extremely powerful and heavily armored, the German tanks had a fatal weak point, they were easily immobilized, and that’s was what the FV4005’s HESH shells do with extremely efficacy. The immobilized tank were easy to take down by anti-tank infantry, bombers, artillery and the FV4005’s itself. The allies won with a great strategy, surprise factor and better knowledge of the terrain, but not without heavy losses. The FV4005’s were crucial for the win, hidden and far from the enemies range, they bombarded the Nazi forces, causing heavy damage and great confusion to the tanks and infantry.
Between those 25 FV4005’s, there was 1 who highlighted itself for its great performance. Taking out over 1 Pz. VIII Maus, 1 Pz. VI Tiger II, 8 Pz. IV and 21 light armored vehicles alone during the 23 hours conflict, not counting it’s infantry kills with indirect damage and missed shots. It is said by its crew that one shot incapacitated 4 light vehicles at once, and only one shot was enough to exploded the Maus turret. That tank was named “Lancelot” and its extra frontal armor plate was painted with a mix between England and Sweden flag, to remember its legendary and glorious first fight. Some other modifications were done, like the installation of and 15mm Besa machine gun in the place of the 7.62mm originally installed, the extra armor plate said earlier, smoke grenade launchers and others. After that, the “Lancelot” was seen in many other battles until the end of the war in 1957. Its crew mastered how to use their vehicle and created a bond with it, becoming extremely efficient with its vehicle and seen as a devil through the eyes of the enemies.

Real History of the FV4005:

The Project

During the development phase of the FV215B, another project was done on the Centurion. Labeled the FV4005, it was an attempt to mount the 183 mm on the Centurion hull. The design phase is distinctive in two parts, Stage I and II. Stage I had the gun mounted on an open-topped hull. The gun had a concentric recoil system and an auto-loader. Stage II had the gun encased in a lightly armoured, splinter-proof turret with a conventional recoil system and manual loading.

The Turret

Despite being an extremely prominent target, the turret armor was only 14 mm (0.55 in) at its thickest. This was easily penetrable even by large caliber machine guns rounds. It also only had enough space to store 12 rounds . These rounds were stored in racks of 6 on each side of the large bustle.
The turret housed 4-5 crewmembers. These were the commander on the forward left, gunner on the front right and 2 loaders positioned behind the gun. On the left of the gun, in a small box on the cheek, was a coaxial .30 cal machine gun. This was most likely used for ranging rather offensive/defensive fire. There was a large door in the rear of the turret bustle for crew access and ammunition re-supply. The driver was located in the standard position in the hull
It should be noted that the lack of armor was intentional. This vehicle was designed to engage at long-range, shoot and re-position. Flexibility was slightly hampered by the turret, however. In theory, it was fully traversable. On uneven ground, this was not recommended due to balancing issues with the gun. As such, the vehicle only really had a 90 degrees arc of fire to the left and right.

The Gun

In 1950, work started on the Ordnance Quick Firing 183 mm (7.2 in) L4 gun. At the time, it was the largest and most powerful tank gun in the world. The cannon was based on the 183 mm (7.2 in) BL 7.2 inch howitzer, a WWI era weapon. The gun itself weighed a mighty 4 tons and when fired it produced the equivalent of 87 tons of recoil force. The L4 was designed to be chambered for only one type of ammunition, HESH (High Explosive Squashed Head).
It was separately loading ammunition. The projectile was loaded first followed by the correct propulsion cartridge. Each shell weighed a combined total of 104.8 kg. A shell of this size understandably produced a substantial amount of fumes and smoke inside of the fighting compartment. As such, a large fume extractor was added to the barrel, a relatively new feature at the time. The L4 was expected to have a rate of fire of six rounds per minute, but even with two loaders on service, the weapon took from 45 to 30 seconds to reload.
The 183 mm was tested in live fire trials against a Centurion and a Conqueror. In two shots, the 183 blew the turret clean off the Centurion and split the mantlet of the Conqueror in half. In total, the gun fired 150 shells.

The Lone Guardian

Though a single prototype was made for testing, the project never passed basic feasibility. In August 1957, the project was abandoned as well. The lone prototype is currently stationed outside at Bovington Tank Museum.
The FV4005 Stage II is the only one of these 183mm armed vehicles to survive to this day. The turret is original, but it was mounted on a spare Mk.VIII Centurion hull, not the original it was trialed with. It is missing the recoil spade and travel lock. This “Cut-and-Shunt” representation of the vehicle now sits as a “gate-guardian” at The Tank Museum, Bovington, alongside an M4 Sherman. Its predecessor, the FV4004 Conway is safe and sound in the VCC (Vehicle Conservation Center) at the site.

The FV4005 (on a Centurion Mk.III hull) as it stands today outside the Bovington Tank Museum

I think that is all, I tried my best for make it realistic, I hope you like it. Thanks for the support of all and the tips, comment what you think of this project and upvote also, enjoy and see my other projects, I know you will like, Ideas to improve my projects are always welcome, please if you really like this project upvote, do not forget. Also, sorry for my English.

Credits:

@RussianAce – A lot of part used in this build are inspired, modified or simple copies of some parts he used in his work.
@Minecraftpoweer – the gun holder is basically a copy from his Obj. 263.
@MisterT – creator of the map used for screenshots, Stork Island.

Gallery: