A multipurpose aircraft.
This isn't some hobbyist's dream, but it is an aircraft with a multi-function capability to switch from a manned to an unmanned configuration in only four hours. See Northrop Grumman Plans To Upend Aerial Surveillance Market With Their Optionally Manned Firebird.
In this case, the battery life is not a consideration and it will have a long linger time for any mission parameter you might need in a disaster scenario. Owners and operators in the civil world would have to be large counties, states or perhaps industry.
Don Villeneuve shared the link above.