4Game

Elementary School Math Rant.

https://en.wikipedia.org/wiki/Panhard_EBR

The EBR can reach speeds of 100 km/h (62 mph) on 14 in (36 cm)-wide, 24 in (61 cm)-diameter wheels with Michelin tyres and Veil-Picard tubes, which feature a series of nitrogen-filled cells, enabling them to absorb bullet hits and not go flat. The armoured hull is mounted on an 8-wheel drive, with 4 inner metal wheels, which can be raised for driving on the road. The four central wheels have aluminum rims with steel grousers, separated by rubber blocks; with all eight wheels deployed, ground pressure is only 0.7 kg (1.5 lb) per 1 cm2 (0.16 in2).

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So, indulge my elementary school math here (Yes, I've learned these in Elementary school in the early 90s in Greece). I will keep it mostly in "Imperial" / inches & lbs because easier with the specific numbers in this example:

1. The Panhard EBR was 14 short tons, or 14*2,000lbs/ton = 28,000 lbs.
2. We assume it is true that it treaded on 14in wide wheels. For convenience lets say that this is how wide the tires were too.
3. The claimed ground pressure (my beef) with all wheels deployed is .7kg/cm^2. An online unit converter will reveal to you this being shy of 10 psi.
4. So we have 10psi of claimed ground pressure, on a 28,000 lbs vehicle. That means that the combined contact patch of 8 wheels has to be 28,000 lbs / 10 lbs per square inch = 2,800 square inches.
5. From #2, we are told that the wheels are ~14in wide. Thus the contact patch length of all 8 wheels from #2 & #4 is 2,800 in^2 / 14 in = 200 in, or 200in / 8 wheels = 25in per wheel. I would think it is pretty preposterous to claim that a pretty rigid wheel with a diameter less than 48in, can have a contact patch length of 25in…especially when half the wheels have tires with compartmentalized tubes so not to get flat (by BULLETS tho ppl, BULLETS, not shells, jeez) and the other half are rigid full aluminum wheels…

So, Wikipedia contributor, please edit those things out. Perhaps WG in its infinite wisdom will see it and nerf the ground resistances the EBRs get. Newsflash: ground resistances on Wheeled vehicles on soft should be worse than half those of tracked vehicles i.e. the very reason we still have tracked vehicles.

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Also, kindly note that the RL pw/wt of the Pahnard EBR is roughly 1/3 of what is modeled in-game, but that might be the subject of another rant.