Simple off-road "big" cargo trucks

[BATTLEMASTER]

These are inspired by the "big" off-road cargo trucks fielded by the US armed forces throughout the years, at least up until about 2010 or 2015 (except for the HEMTT which is still in service).  They're meant to be cheap, simple, and get the job done.  All these trucks IRL have variants that include van bodies, rotating cranes or heavy underlifts for vehicle recovery, liquid tanks, and firefighting apparatus.  They can also tow trailers, of course the bigger the truck the bigger the trailer they can tow!  Using the heavy cargo rules (or exterior cargo rules maybe?), these trucks can carry more cargo on paved roads without losing speed like IRL, although the FMTV weren't designed as such, nor was the M35A3!

Code: [Select]

Truck, Cargo: 10 Ton, 8X8 HEMTT M977
<p>
<b>Mass: </b>28 tons<br/>

<b>Movement Type: </b>Wheeled<br/>

<b>Power Plant: </b> ICE<br/>
<b>Cruising Speed: </b>54 kph<br/>
<b>Maximum Speed: </b>86.4 kph<br/>
<b>Armor: </b>BAR 2</b><br/>
<b>Armament:</b><br/>


<b>Communication System: </b>Unknown<br/>
<b>Targeting & Tracking System: </b>Unknown<br/>
<b>Introduction Year:</b> 3145<br/>
<b>Tech Rating/Availability:</b> D/X-X-X-B<br/>
<b>Cost:</b> 183,326 C-bills<br/>
</p>




 
Type: Truck, Cargo: 10 Ton, 8X8
Chassis Type: Wheeled (Medium)
Technology Base: Inner Sphere (Standard)
Mass: 28 tons
Battle Value: 38

Equipment                                         Mass (tons)
Chassis/Controls                                    8.0
Engine/Trans.                                      12.5
    Cruise MP:5
Flank MP:8
Heat Sinks                    0                     0.0
Fuel                                                1.0
Armor Factor (BAR 2)          12                    0.5

                          Internal   Armor   
                          Structure  Value   
     Front                   2         3     
     R/L Side               2/2       3/3   
     Rear                    2         3     


Weapons
and Ammo              Location    Tonnage   
None

Cargo
    Bay 1:  Cargo (3.0 tons)        1 Door   

Notes:
Features Off-Road, Tractor Chassis and Controls Modifications
Lift Hoist/Arresting Hoist(3 tons)



Code: [Select]

Truck, Cargo: 5 Ton, 6X6 M925A2
<p>
<b>Mass: </b>14.5 tons<br/>

<b>Movement Type: </b>Wheeled<br/>

<b>Power Plant: </b> ICE<br/>
<b>Cruising Speed: </b>43.2 kph<br/>
<b>Maximum Speed: </b>64.8 kph<br/>
<b>Armor: </b>BAR 2</b><br/>
<b>Armament:</b><br/>


<b>Communication System: </b>Unknown<br/>
<b>Targeting & Tracking System: </b>Unknown<br/>
<b>Introduction Year:</b> 3145<br/>
<b>Tech Rating/Availability:</b> D/X-X-X-B<br/>
<b>Cost:</b> 32,926 C-bills<br/>
</p>




 
Type: Truck, Cargo: 5 Ton, 6X6
Chassis Type: Wheeled (Medium)
Technology Base: Inner Sphere (Standard)
Mass: 14.5 tons
Battle Value: 25

Equipment                                         Mass (tons)
Chassis/Controls                                    5.5
Engine/Trans.                                       4.5
    Cruise MP:4
Flank MP:6
Heat Sinks                    0                     0.0
Fuel                                                0.5
Armor Factor (BAR 2)          12                    0.5

                          Internal   Armor   
                          Structure  Value   
     Front                   2         3     
     R/L Side               2/2       3/3   
     Rear                    2         3     


Weapons
and Ammo              Location    Tonnage   
None

Cargo
    Bay 1:  Cargo (3.0 tons)        1 Door   

Notes:
Features Off-Road, Tractor Chassis and Controls Modifications



Code: [Select]

Truck, Cargo: 2.5 Ton, 6X6 M35A3
<p>
<b>Mass: </b>8.5 tons<br/>

<b>Movement Type: </b>Wheeled<br/>

<b>Power Plant: </b> ICE<br/>
<b>Cruising Speed: </b>43.2 kph<br/>
<b>Maximum Speed: </b>64.8 kph<br/>
<b>Armor: </b>BAR 2</b><br/>
<b>Armament:</b><br/>


<b>Communication System: </b>Unknown<br/>
<b>Targeting & Tracking System: </b>Unknown<br/>
<b>Introduction Year:</b> 3145<br/>
<b>Tech Rating/Availability:</b> D/X-X-X-B<br/>
<b>Cost:</b> 23,456 C-bills<br/>
</p>




 
Type: Truck, Cargo: 2.5 Ton, 6X6
Chassis Type: Wheeled (Medium)
Technology Base: Inner Sphere (Standard)
Mass: 8.5 tons
Battle Value: 16

Equipment                                         Mass (tons)
Chassis/Controls                                    2.5
Engine/Trans.                                       2.0
    Cruise MP:4
Flank MP:6
Heat Sinks                    0                     0.0
Fuel                                                0.5
Armor Factor (BAR 2)          12                    0.5

                          Internal   Armor   
                          Structure  Value   
     Front                   1         3     
     R/L Side               1/1       3/3   
     Rear                    1         3     


Weapons
and Ammo              Location    Tonnage   
None

Cargo
    Bay 1:  Cargo (3.0 tons)        1 Door   

Notes:
Features Off-Road, Tractor Chassis and Controls Modifications



[Daryk]

Just so you know, code tags ignore ALL tags inside them...

[BATTLEMASTER]

Just so you know, code tags ignore ALL tags inside them...

I noticed that.  It seems to be a bug with MegaMekLab when exporting support vehicle stats to clipboard as text.  It's an older version I'm using though, and I can't remember if it's been fixed since.

[DevianID]

I like the concept (and have done similar for personnel use) but my suggestion is to consider curb weight since you are basing these vehicles off real ones.  Thus, a 5 ton truck has a curb weight of 9-10 tons based off model, but 0 of that is cargo.  It can carry 5 tons (4500 kg, so 4.5 btech tons) and another 4.5 tons on roads.  In btech, you can carry up to your weight max, which is also 9 tons for a 9 ton empty weight truck.  Thus your 5 ton 6x6 can be designed as a 9 ton vehicle, not a 14.5 ton vehicle with cargo.  Your 14.5 ton 6x6 vehicle can carry 3 tons internally, plus another 29 tons after that, which excedes what the 10 ton wrecker trucks did!

The 2.5 ton real life truck was 5800 kg empty, and could carry 4500 kg max, thus a btech deuce and a half would be 5ish tons.
The 10 ton Real truck was 14-15 tons, and could carry (3,600 kg) while towing up to 60,000 lb (27,000 kg), which again hits btechs figures for a 14 ton truck carrying 28 tons and a 15 ton truck carrying 30 tons.

[BATTLEMASTER]

I worked backwards a little bit and considered the gross vehicle weight rating (GVWR) of each vehicle.  I was trying to get the overall mass of the trucks to work out with what we'd see today.  I think that since MegaMekLab is rounding to the nearest half-ton, I'm pretty close overall.

I was also thinking about the cargo weight ratings and how to address them.  In most scenarios I would use them, they would be working off-road, which could be anything from what we see on the BattleTech map sheets or a bulldozed path through the woods or wherever.  Therefore I designed them for their off-road rating, assuming that any speed loss they'd get from overloading per the rules would be made up by presumably driving on a paved surface.  I also assumed that top speed would be achieved only through sprinting since these trucks usually drive comfortably at the speeds I specified in their designs like IRL.

Fun fact:  The M35A3 is actually about 1300 kg heavier than the earlier M35 models because of the upgrades made to them to help them supplement the delivery of the LMTV in the 1990s.  The upgrades made the truck quicker to accelerate from a stop and go up a hill, but the automatic transmission's gearing cut the top speed down a few MPH.

I can nerd out about real army trucks all day 

[Daryk]

When I made my trucks, I standardized on the 25-rated engine.  The 5-ton jeep was 9/14, the 9-ton truck was 5/8, the 15-ton one 3/5, and the 45-ton one 1/2.

[DevianID]

I worked backwards a little bit and considered the gross vehicle weight rating (GVWR) of each vehicle.

While I see how you figured it, that still leaves the issue that your 5 ton 6x6 at 14.5 tons is hauling 29+3 tons--which is 10 ton truck specs.
The off road cargo of real world trucks being half the full load is better addressed with a fluff quirk that these trucks are built to primitive standards, and only haul half their standard load off road instead of 100% of their weight.

This way a 9 ton truck empty in btech is 13.5 tons under load off road, which is pretty much the gross weight you are figuring as that includes cargo.