How do the flight decks work in unison on the Stratolaunch?
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 what looks like a cockpit with windows to
  onlookers, but the section is in fact empty and unpressurised.


It does look like there both fuselages have cockpits.


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