CastIron888

Oh, I see.

I was responding to the more general statement:

You do not want the stressed members of any structure being a salient contributor to its power-train. Not related, see mammalian, reptile, fish, and insect physiologies.

A steam traction engine is certainly at a different level to an F1 car, in both performance and engineering.

On the other hand, I think adding dynamic load to a steam boiler is riskier than doing so to an internal combustion engine.

You can see in the picture the boiler is taking the load of the machine. There is no additional chassis.

That's less frame than a Ducati has between the front and rear wheels.

Without speaking to the wisdom of stressing batteries mechanically, the idea of using drivetrain components as structural members of a vehicle is as old as self-propelled vehicles.

Hell, even a chariot sees the horse taking a part of the vehicle load.

Not old enough?

How about a steam engine with the front axle bolted to the boiler?

A steam boiler is subject to considerable stresses already and adding dynamic forces to the shell can't be a good idea?

https://upload.wikimedia.org/wikipedia/commons/4/42/Kemna_ro...

The Fordson tractor of 1917 appears to use the engine block and transmission case as basic structural members of the tractor.

Not a fast vehicle, but tough.