Section 240. Definitions

When used in this article,
    1.  "Aircraft"  means  any contrivance, now or hereafter invented, for
  avigation of  or  flight  in  the  air,  except  a  parachute  or  other
  contrivance   designed   for  use,  and  carried  primarily  for  safety
  equipment.
    2. "Avigation"  means  the  steering,  directing  or  managing  of  an
  aircraft,  in  or  through  the  air;  and  such  term is here used as a
  substitute for "aerial navigation."
    3. "Operating aircraft" means  performing  the  services  of  aircraft
  pilot.
    4.  "Landing  area"  means  any  locality  either  of  land  or water,
  including airports and intermediate landing fields,  which  is  used  or
  intended to be used for the landing and take-off of aircraft, whether or
  not facilities are provided for shelter, servicing or repair of aircraft
  or for receiving or discharging passengers or cargo.
    5.  "Airport"  means  any  landing area used regularly by aircraft for
  receiving or discharging passengers or cargo; or  for  the  landing  and
  take-off of aircraft being used for personal or training purposes.
    6.  "Acrobatic flying" means maneuvers not necessary for normal flight
  and intentionally performed by an aircraft, involving an  abrupt  change
  in its attitude, an abnormal attitude or an abnormal acceleration.
    7.   "Administrator   of   the  federal  aviation  agency"  means  the
  administrator of the federal aviation agency of the United States.
    8. "Airplane" means a mechanically propelled aircraft, the support  of
  which  in flight is derived dynamically from the reaction on surfaces in
  a fixed position relative to the aircraft but in motion relative to  the
  air.
    9.  "Control  zone"  means an airspace of defined dimensions extending
  upwards from the surface  of  the  ground  and  including  one  or  more
  airports  and  designated  as  such  by the administrator of the federal
  aviation agency.
    10. "Flight visibility" means the  average  horizontal  distance  that
  prominent objects may be seen from the cockpit.
    11. "Helicopter" means an aircraft, the support of which in the air is
  normally   derived   from   airfoils   mechanically   rotated  about  an
  approximately vertical axis.