User:Doneve/Combat Vehicle Construction Steps

This! Is a step by step introduction, to design various Combat Vehicle models and variants.

Step 1: Design the Chassis

Choose Motive Type

Hephaestus

[Michael] - wants to design a fast and flexible scout and attack unit, and decides on a hovercraft, which he chooses to name the Hephaestus. In preparation for the design process, he gets a copy of a blank Ground Vehicle Record Sheet ready.

Yellow Jacket

[Nathaniel] - is designing an airborne vehicle ideal for recon and attack missions, and selects a VTOL motive type. He chooses the name Yellow Jacket for this unit. Nathaniel prepares a blank VTOL Record Sheet to aid in his design.

Zhukov

[Patrick] - has a more conventional battle tank in mind for his vehicle, and so decides that his unit, the Zhukov, will be a tracked vehicle. Patrick notes from the Combat Vehicle Record Sheet Table that he will use a Ground Vehicle Record Sheet for his design.

Neptune

[Rick] - is looking for a rare item in the Classic BattleTech universe: a submersible coastal defense unit. Naming this craft the Neptune, he decides on a naval (submarine) motive type. Rick must use a Naval Vehicle Record Sheet to plan out his design.

Choose Technology Base

Hephaestus

[Michael] - Because he plans to create this design for a Clan game, Michael chooses a Clan Technology Base for his Hephaestus, and further decides to maximize its fl exibility by developing it as an OmniVehicle.

Yellow Jacket

[Nathaniel] - chooses the Inner Sphere Technology Base for his Yellow Jacket, and has elected not to make it an OmniVehicle.

Zhukov

[Patrick] - sees his Zhukov as a bare-bones Capellan-made design, and so he selects an Inner Sphere Technology Base and opts not to make it an Omni.

Neptune

[Rick] - chooses an Inner Sphere Technology Base for his Neptune, and also decides not to make it an Omni.

Choose Weight Tonnage

Hephaestus

[Michael] - plans to make his Hephaestus a nimble speedster. Because it is a hover vehicle, the Hephaestus has a maximum weight limit of 50 tons. Mike decides that a nice, round 30 tons will be suitable for his needs. At this weight, he calculates that the vehicle will have 11 items of weapon and equipment space (5 + [30 tons ÷ 5] = 11 items).

Yellow Jacket

[Nathaniel] - As a VTOL, Nathaniel's Yellow Jacket cannot exceed a 30-ton maximum weight for its motive type. With ambitious plans in mind, he chooses to design his Jacket as a 30-tonner. The Yellow Jacket also has space for 11 items (5 + [30 tons ÷ 5] = 11 items).

Zhukov

[Patrick] - decides his Zhukov will weigh in at 75 tons, on the heavy side of the 100-ton maximum permissible for tracked vehicle types. At this weight, the Zhukov has space for up to 20 items (5 + [75 tons ÷ 5] = 20 items).

Neptune

[Rick] - decides his Neptune should be large, to maximize its armor and firepower in underwater combat. He chooses a weight of 100 tons, noting that—as a submarine—he could have gone as high as 300 tons. The 100-ton weight nonetheless gives the Neptune space for 25 items (5 + [100 tons ÷ 5] = 25 items).

Allocate Tonnage for Internal Structure

Hephaestus

[Michael] - With a weight of 30 tons, Mike determines that his Hephaestus' internal structure will weigh 3 tons (10 percent of 30 tons = 0.10 x 30 tons = 3 tons). He also determines that the Hephaestus will receive 3 internal structure points per location (10 percent of 30 tons = 0.10 x 30 tons = 3). As the Hephaestus is an OmniVehicle, Mike must determine at this time whether or not it will have a turret, and how much said turret will weigh. He decides to equip the unit with a turret that can mount up to 5 tons' worth of weapons, and so spends an additional 0.5 tons on turret equipment (10 percent of 5 tons [expected mass of turret weapons] = 0.10 x 5 tons = 0.5 tons). This leaves the Hephaestus with 26.5 tons of unspent weight (30 tons – 3 tons [structure] – 0.5 tons [turret] = 26.5 tons).On the Hephaestus' Armor Diagram, Mike blacks out all but 3 circles in each of the five gray-shaded areas that indicate the vehicle’s internal structure.

Yellow Jacket

[Nathaniel's] - Yellow Jacket weighs 30 tons as well, and so he also computes a 3-ton weight for internal structure (10 percent of 30 tons = 3 tons). He also computes a 3-point value for each of the VTOL's internal structure locations, including the rotor (10 percent of 30 tons = 3 points per location). Because the record sheet already shows 3 points per location for the VTOL's internal structure, Nathaniel has no structure circles to black out (but if he had built his Yellow Jacket 10 tons lighter, he would have). The Yellow Jacket has 27 unspent tons remaining (30 tons – 3 tons = 27 tons).

Zhukov

[Patrick's] - Zhukov weighs 75 tons. From that he finds that its internal structure will weigh 7.5 tons (10 percent of 75 tons = 0.10 x 75 tons = 7.5 tons). The number of structure points provided per location, meanwhile, will be 8 (10 percent of 75 tons = 0.10 x 75 = 7.5, rounded up to 8 points). Because he plans on mounting a turret, Patrick blacks out all but 8 circles in each of the 5 internal structure locations on his Zhukov's Armor Diagram. Because the Zhukov is not an OmniVehicle, however, Pat will not need to compute the turret’s weight at this time, and so he still has 67.5 unspent tons remaining (75 tons – 7.5 tons = 67.5).

Neptune

[Rick] - At 100 tons, Rick's Neptune will need to spend 10 tons on internal structure (10 percent of 100 tons = 10 tons), and will receive 10 points of internal structure per location as a result (10 percent of 100 = 10 points). Rick decides, however, that his sub will not require a turret, and so he blacks out all of the circles in the Turret location on the Neptune's Armor Diagram (including the internal structure circles in the gray-shaded area and the armor circles in the unshaded Turret area). For the other four locations (Front, Left, Right and Rear), Rick only blacks out all the excess structure circles, leaving 10 per location. The Neptune now has 90 tons left to spend (100 tons – 10 tons = 90 tons).

Step 2: Install Engines and Control Systems

Install Engine

Hephaestus

[Michael] - Because his Hephaestus is intended primarily as a recon unit, high speed is Michael's primary focus. He thus decides to give the hovertank a Cruising MP rate of 8 (thus attaining a Flank MP of 12, as 8 MP x 1.5 = 12 MP). This means that the Hephaestus' Base Engine Rating will be 240 (30 tons x 8 MP = 240). However, Mike also notes that according to the Combat Vehicle Suspension Factors Table, a hovertank weighing 21 to 30 tons has a Suspension Factor of 130. This means Mike's vehicle will have a Final Engine Rating of 110 (240 Base Engine Rating – 130 Suspension Factor = 110 Final Engine Rating). Looking at the Master Engine Table, Michael notes that a standard 110-rated fusion engine weighs 3.5 tons, but because it is a fusion engine, he must add another 50 percent to this fi gure to account for added shielding, raising the engine weight to 5.5 tons (3.5 tons x 1.5 = 5.25 tons, rounded up to the nearest half-ton for 5.5). However, even then the engine weighs less than the minimum 6 tons he needs to devote to engine mass for his hover vehicle (20 percent of 30 tons = 0.2 x 30 tons = 6 tons). Rather than increase the vehicle's speed to a Cruising MP of 9 (which would produce an Engine Rating of 190, and require a 7.5-ton fusion engine), Mike accepts an automatic increase of half a ton in engine weight to "force" the engine to a 6-ton size (5.5 tons [engine with shielding] + 0.5 tons [added weight] = 6 tons). Because he opted to use a standard Fusion engine rather than an XL, Michael's hovertank loses no item slots to engine installation. Upon installing the engine, Mike notes that his Hephaestus still has 20.5 unspent tons remaining (26.5 tons – 6 tons = 20.5 tons).

Yellow Jacket

[Nathaniel] - wants his Yellow Jacket to be fast, but is also thinking about packing some heavy firepower on it, so he decides on a modest VTOL Cruising speed of 6 MP. This gives the Jacket a Flank speed of 9 MP (6 Cruising MP x 1.5 = 9 Flank MP). It also yields an Engine Rating of 40 ([30 tons x 6 Cruising MP] – 140 Suspension Factor [for a 30-ton VTOL] = 40 Final Engine Rating). To keep production costs low, Nathaniel opts for an internal combustion engine. On the Master Engine Table, he finds that a 40-rated ICE weighs only 2 tons, leaving the Yellow Jacket with 25 unspent tons remaining (27 tons – 2 tons = 25 tons). Because he opted to use a standard IC engine rather than a Light or XL Fusion plant, Nathaniel's VTOL loses no item slots to engine installation.

Zhukov

[Patrick] - plans to devote more of his Zhukov's weight to armor and weapons, and because he wants to make this vehicle a defensive battle tank, he decides on a Cruising MP of 3. This requires an Engine Rating of 225 ([75 tons x 3 Cruising MP] – 0 Suspension Factor [for tracked vehicles of any size] = 225 Final Engine Rating). Like Nathaniel, Pat plans to keep the costs low on this design, and so he also opts for an ICE over a Fusion engine. The Master Engine Table shows that a 225-Rated ICE will take up a hefty 20 tons. (By way of comparison, an identically rated standard Fusion engine would weigh 15 tons, with its added shielding, but would drive up the Zhukov's C-bill cost dramatically.) Sticking with his choice, Pat computes that his Zhukov still has 47.5 unspent tons left (67.5 tons – 20 tons = 47.5 tons), and has a Flank MP rate of 5 (3 Cruising MP x 1.5 = 4.5 Flank MP, rounded up to 5). Like Nathaniel's VTOL, Patrick's tracked vehicle loses no item slots because it uses a standard IC engine, rather than a Light or XL Fusion plant.

Neptune

[Rick] - For his Neptune submarine, Rick feels a Cruising MP of 3 is fine for underwater movement. Like Nathaniel and Patrick, he also opts for a cheaper ICE to do the job, and computes an Engine Rating of 270 for the vessel ([100 tons x 3 Cruising MP] – 30 Suspension Factor for submarines of any weight = 270 Final Engine Rating). The weight of a 270-rated ICE comes to 29 tons, leaving 61 tons unspent so far (90 tons – 29 tons = 61 tons). The Neptune's engine will provide a Flank MP rate of 5 (3 Cruising MP x 1.5 = 4.5, rounded up to 5 MP), so long as the boat stays in the water. The use of the IC engine does not reduce the Neptune's maximum number of items.

Add Lift/Dive Equipment or Rotors

Hephaestus

[Michael's] - Hephaestus is a hovercraft, which requires lift equipment to remain aloft during movement. The weight of this equipment is 3 tons (10 percent of 30 tons = 0.1 x 30 tons = 3 tons), leaving the vehicle with 17.5 unspent tons remaining (20.5 tons – 3 tons = 17.5 tons).

Yellow Jacket

[Nathaniel's] - Yellow Jacket VTOL needs to invest 10 percent of its weight into its rotor equipment. This will leave the craft with 22 unspent tons (25 tons – 3 tons = 22 tons).

Zhukov

[Patrick's] - Zhukov, as a tracked Combat Vehicle, has no need for lift or dive equipment and rotors. It thus still has 47.5 tons remaining.

Neptune

[Rick] - At 100 tons, the dive equipment for Rick's Neptune comes to 10 tons (10 percent of 100 tons = 10 tons). The vessel still has 51 tons of unspent weight (61 tons – 10 ton = 51 tons).

Add Control Systems

Hephaestus

[Michael] - The controls for Michael's Hephaestus weigh in at 1.5 tons (5 percent of 30 tons = 0.05 x 30 tons = 1.5 tons), leaving the vehicle with 16 unspent tons remaining (17.5 tons – 1.5 tons = 16 tons). Michael further computes that his Hephaestus operates on a 2-man crew (30 tons ÷ 15 tons per crew-man = 2 crewmen).

Yellow Jacket

[Nathaniel's] - Yellow Jacket VTOL requires 1.5 tons' worth of control equipment as well (5 percent of 30 tons = 0.05 x 30 tons = 1.5 tons), leaving 20.5 tons remaining (22 tons – 1.5 tons = 20.5 tons). The VTOL also requires a crew of 2 to operate (30 tons ÷ 15 tons per crewman = 2 crewmen).

Zhukov

[Patrick's] - Zhukov, a significantly heavier vehicle, requires 4 tons of control systems to operate (5 percent of 75 tons = 0.05 x 75 = 3.75, which rounds up to 4 tons). This leaves the tank with 43.5 tons remaining (47.5 tons – 4 tons = 43.5 tons). Based on the crew formula, the Zhukov needs 5 crewmen to operate it (75 tons ÷ 15 tons per crewman = 5 crewmen).

Neptune

[Rick] - The controls for Rick's 100-ton Neptune come to 5 tons (5 percent of 100 tons = 5 tons), bringing the vessel's unspent weight down to 46 tons (51 tons – 5 tons = 46 tons). To operate, the Neptune requires a crew of 7 (100 tons ÷ 15 tons per crewman = 6.67, rounded up to 7 crewmen).

Step 3: Add Heat Sinks

Heat Sinks

Hephaestus

[Michael] - The fusion engine installed on Michael's Hephaestus provides 10 heat sinks without cost. Mike decides that this is sufficient for his hovertank's needs, noting that—as an OmniVehicle—he can always add more if a later configuration so requires. As heat sinks occupy no space in a Combat Vehicle design, the Hephaestus loses no item slots for having sinks.

Yellow Jacket

[Nathaniel's] - Yellow Jacket VTOL uses an ICE, and so receives no free heat sinks. Because he does not plan to install energy weapons, he elects not to add any.

Zhukov

[Patrick's] - Zhukov is also being planned as a ballistic-based Combat Vehicle, and so he is equally satisfied with having no heat sinks due to the selection of an IC engine.

Neptune

[Rick] - has decided to mount energy weapons on his Neptune, but because he has chosen an internal combustion engine, he has received no free heat sinks to handle any such weapons. With his eye on a standard large laser, he decides to add 8 heat sinks to the vessel, to vent the 8 points of heat the weapon would generate. At 1 ton per heat sink, Rick finds that he has 38 unspent tons remaining (46 tons – 8 tons = 38 tons). Heat sinks take up no item space in Combat Vehicle design, so Rick moves on to the next step.

Step 4: Add Armor

Combat Vehicle Armor

Hephaestus

[Michael's] - Hephaestus has 16 tons remaining. Given its weight, he computes that the maximum armor he can place on the vehicle is 145 points ([3.5 x 30 tons] + 40 = 145 points). Mounting that many points—even using Clan ferro-fibrous armor—would cost him 8 tons, however (145 points ÷ [16 Base Points per Ton x 1.2 Clan Ferro-Fibrous Multiplier] = 7.552, rounded up to 8). Unwilling to go quite that far, Mike decides to install only 5 tons of Clan ferro-fibrous armor, which gives him 96 armor points to allocate instead (5 tons of armor x 16 Base Armor Points per Ton x 1.2 Clan Ferro-Fibrous Multiplier = 96 points). Michael decides to distribute most of this armor toward the front and sides of the vehicle, where he feels it is most likely going to be hit, and so he places 20 points of armor each in the Front, Left Side and Right Side locations. The remaining 36 points he divides evenly among the Rear and Turret locations at 18 points apiece. Verifying that all points are accounted for, Mike adds all the armor values together: 20 [Front] + (20 + 20 [Left Side, Right Side]) + 18 [Rear] + 18 [Turret] = 96. In the appropriate non-shaded locations of the Hephaestus' Armor Diagram, Michael blacks out all extra circles, leaving only the assigned amount for each location. With 5 tons spent on armor now, the Hephaestus has only 11 tons remaining for weapons and other equipment (16 – 5 = 11). Michael also notes he has 1 fewer item slots remaining in which to assign equipment, thanks to his use of Clan ferro-fibrous armor, meaning that his vehicle can only mount 10 items now (11 slots – 1 item = 10 slots).

Yellow Jacket

[Nathaniel] - Still looking to keep costs low and preserve as much weight for weaponry as possible, Nathaniel chooses to mount 3.5 tons' worth of standard armor on his Yellow Jacket. Like Michael’s Hephaestus, the 30-ton VTOL has a maximum armor potential of 145 points ([3.5 x 30 tons] + 40 = 145 points), but using standard armor would cost more than 9 tons to accomplish (145 points ÷ [16 Base Points per Ton x 1 Standard Armor Multiplier] = 9.06, rounded up to 9.5 tons).The 3.5 tons Nathaniel chooses provides 56 points of armor (3.5 tons x 16 Base Points per Ton x 1.0 Standard Armor Multiplier = 56 points). He chooses to mount the majority of this armor on the Yellow Jacket's nose, with 20 points to that location. As the rotor location cannot receive more than 2 points of armor, Nathaniel places the maximum of 2 points there, before mounting 13 armor points on each of the VTOL’s sides and 8 points on the rear. Verifying his numbers, he adds up the armor points: 20 [Nose] + (13 + 13 [Left and Right Sides]) + 8 [Rear] + 2 [Rotor] = 56 points. Nathaniel blocks out all the excess armor points in each location on the Yellow Jacket’s Record Sheet. Because he used standard armor rather than ferro-fibrous, the Yellow Jacket sees no loss in item space on its inventory. It now has 17 tons of unspent weight remaining (20.5 tons – 3.5 tons = 17 tons).

Zhukov

[Patrick] - At 75 tons, Patrick's Zhukov could mount as much as 302 points of armor ([3.5 x 75 tons] + 40 = 302.5 points, round down to 302), but doing so would cut deeply into the 43.5 tons remaining to be spent. Pat thus decides to devote 11 tons to armor, and chooses standard armor to keep costs low. At 11 tons, the Zhukov will receive 176 armor points (11 armor tons x 16 Base Points per Ton x 1.0 Standard Armor Multiplier = 176 points). Patrick distributes his armor points with a heavy emphasis on the Front and Turret locations, where he places 44 points each. On the sides, he assigns 32 points each, before allocating the remainder—24 points—to the rear. Verifying his numbers, he adds up the assigned armor points: 44 [Front] + (32 + 32 [Left and Right Sides]) + 24 [Rear] + 44 [Turret] = 176 points. On his Vehicle Record Sheet, Pat blacks out all the excess points for each of the Zhukov's non-shaded armor locations, based on these figures. With 11 tons spent on armor, the Zhukov now has 32.5 unspent tons remaining (43.5 – 11 = 32.5). Because Pat chose standard armor over ferro-fi brous, the vehicle also retains all 20 of its original item slots.

Neptune

[Rick] - decides that his 100-ton Neptune can afford to spend 14.5 tons on standard armor, which will yield a total of 232 points (14.5 armor tons x 16 Base Points per Ton x 1.0 Standard Armor Multiplier = 232). Just to be sure, however, he verifies that he is not exceeding the vehicle's maximum armor potential, and finds that the submarine could take on as much as 390 points in all ([3.5 x 100 tons] + 40 = 390 points). With no turret to place armor on, Rick has only 4 facings among which to distribute his 232 armor points. He assigns 78 points to the front, while the sides receive 58 points each and the rear receives 38. Summing up, he verifies the armor is fully assigned: 78 [Front] + (58 + 58 [Left and Right Sides]) + 38 [Rear] = 232 points. On the Neptune's Record Sheet, he then blacks out all excess armor circles in each of the affected locations, making sure to black out all armor circles for the turret. Because Rick used standard armor rather than ferro-fibrous, the Neptune does not lose any item spaces from its inventory. It now has 23.5 tons of unspent weight remaining (38 tons – 14.5 tons = 23.5 tons).