Depends on how you define it but there have been a variety over the years:
The P-38 Lighting has 3 bodies there was also a later experimental version the XP-49 that only saw a single airframe.
The F-82 was a a twin fuselage version of the P-51
The boomerang which was also designed by Burt Rutan (the designer of the stratolaunch)
A one off twin fuselage ...
On Stratolaunch Systems, there will only be one cockpit as mentioned here:
The pilot, co-pilot and flight engineer will be in the right fuselage
cockpit, while the left fuselage one is empty and unpressurized.
News can be misleading. This article's title says that each fuselage has its own cockpit but later, it clarifies:
The left-hand fuselage has ...
There is indeed an Eigenmode possible on the Stratolaunch which does not exist on regular airplanes: If the two fuselages pitch in opposite direction, thereby twisting the center wing. If that happens at the torsional eigenfrequency of the center wing, flutter might be possible.
Stratolaunch in flight (picture source)
Given the pitch damping of the ...
That would be under Title 14 CFR, Chapters 400-460.
A lot of this stuff really hasn't been finalized yet and these vehicles are considered only experimental and regulated similar to homebuilt aircraft. Passengers are required to sign waivers advising them of their risk and that they understand this and hold the organization indemniable to any and all ...
That's not how airplanes work. An airplane is the wing first, everything else just hangs on the wing in flight.
The correct way to look at an airplane is to imagine the wing without all the attachments, then add them one by one as weights. The engines are a semi-exception in that they also pull forward at their attachment points. The fuselages, on the ...
In stratolaunch, the only the right fuselage houses the flight crew i.e. the cockpit. From stratolaunch.com:
The right fuselage houses the flight crew and the left fuselage contains flight data systems.
Stratolaunch, image from bubblemania.fr; original appears to be from stratolaunch.com