14 CFR § 23.2005 - Certification of normal category airplanes.
(a) Certification in the normal category applies to airplanes with a passenger-seating configuration of 19 or less and a maximum certificated takeoff weight of 19,000 pounds or less.
(b) Airplane certification levels are:
(1) Level 1—for airplanes with a maximum seating configuration of 0 to 1 passengers.
(2) Level 2—for airplanes with a maximum seating configuration of 2 to 6 passengers.
(3) Level 3—for airplanes with a maximum seating configuration of 7 to 9 passengers.
(4) Level 4—for airplanes with a maximum seating configuration of 10 to 19 passengers.
(c) Airplane performance levels are:
(1) Low speed—for airplanes with a VNO and VMO ≤ 250 Knots Calibrated Airspeed (KCAS) and a MMO ≤ 0.6.
(2) High speed—for airplanes with a VNO or VMO > 250 KCAS or a MMO > 0.6.
(d) Airplanes not certified for aerobatics may be used to perform any maneuver incident to normal flying, including—
(1) Stalls (except whip stalls); and
(2) Lazy eights, chandelles, and steep turns, in which the angle of bank is not more than 60 degrees.
(e) Airplanes certified for aerobatics may be used to perform maneuvers without limitations, other than those limitations established under subpart G of this part.