From A-320 AMM:
Hard landing
A hard landing is a landing with an aircraft weight less than the
Maximum landing Weight (MLW) and:
- a vertical acceleration (VertG) equal to or more than 2.6 g and
less than 2.86 g at aircraft Center of Gravity (CG) or,
- a vertical speed (Vs) equal to or more than 10 ft/s and less
than 14 ft/s.
(b) Severe hard landing
A severe hard landing is a landing with an aircraft weight less
than the Maximum landing Weight (MLW) and:
- a vertical acceleration (VertG) equal to or more than 2.86 g at
aircraft Center of Gravity (CG) or,
- a vertical speed (Vs) equal to or more than 14 ft/s.