Here it is
Serious injury means any injury
which: (1) Requires hospitalization for
more than 48 hours, commencing within
7 days from the date of the injury
was received; (2) results in a fracture of
any bone (except simple fractures of
fingers, toes, or nose); (3) causes severe
hemorrhages, nerve, muscle, or tendon
damage; (4) involves any internal
organ; or (5) involves second- or thirddegree
burns, or any burns affecting
more than 5 percent of the body surface.
Substantial damage means damage or
failure which adversely affects the
structural strength, performance, or
flight characteristics of the aircraft,
and which would normally require
major repair or replacement of the affected
component. Engine failure or
damage limited to an engine if only
one engine fails or is damaged, bent
fairings or cowling, dented skin, small
punctured holes in the skin or fabric,
ground damage to rotor or propeller
blades, and damage to landing gear,
wheels, tires, flaps, engine accessories,
brakes, or wingtips are not considered
‘‘substantial damage’’ for the purpose
of this part.
[53 FR 36982, Sept. 23, 1988, as amended at 60
FR 40112, Aug. 7, 1995]
Do you get it yet? Damage to landing gear is not a reportable incident