One of my favorite airplane-related videos is one from the old days during 747 development, where they bent the wing until it broke. Turns out it is extremely strong.

Note: I did a search for that old video and came up with a more recent 777 video instead. Still interesting to see how far they have to bend it before it will break. https://www.youtube.com/watch?v=WRf395ioJRY

This was my first thought as well. But then I remembered that modern twin-engine commercial jets can fly with one engine down in an emergency. Not an aircraft engineer, but I suspect the structure is strong enough to handle normal torques during turning.

The complications with flying a twin engine during a single engine failure have more to do with flight characteristics than structural.

Ie, does the rudder have enough authority to stop a spin or does the engine provide enough thrust to maintain level flight.

The stratolaunch looks to have 2 rudders making things even more exciting.

Heavy turbulence might be exciting, though.

I’m not sure I follow. Unless they did something bananas with the design (which I admit is entirely possible given who designed it), the lift from the wings is transmitted to the rest of the aircraft through a spanwise spar(s). The fuselages hang off of the spar. What forces would rip that apart?

I would expect the forces go both ways. The fuselages have their own forces on the wings and since they are essentially sub-planes I’d imagine the forces could both strong and un coordinated - eg one trying to go one way while the other tries to go the other way. I’m sure under normal circumstances, computers keep everything aligned, but wondering about stressful situations.

Active control systems, presumably.

the center wing structure is strong