The O.R.B. was a brief summary entered in a Squadron log book for each crew after they returned from an "Operation" (mission).
There are usually 4 crews per page with following info; Aircraft Type, Call Letter, Crew names with reg. #, Position, Time up/Time down, Bomb load, Target, Date, Notation if Failed To Return. Written narrative of of flight.
These ORB's are available to purchase at National Archives U.K. Royal Air Force operation record books (approx $7 CAD each) for 22 months 434 Squadron was Operational. Feel free to contact me.
Site Link RAF ORB