From the F.A.I. Sporting Code:
3.1 CLASSIFICATION OF RECORDS
3.1.1 Classes
Aeroplane records (with the exception of Absolute World Records) shall be classified
in one of the following classes:
Class C Aeroplanes
Class H Jetlift
3.1.2 Class C Records
Class C records (with the exception of Absolute World Records) shall further be
classified as one of the following:
C-1 Landplanes
C-2 Seaplanes
C-3 Amphibians
3.1.3 Weight Classification
Aeroplane records (with the exception of Absolute World Records and Speed Over a
Commercial Airline Route records) shall be further classified by weight as follows:
a/o weight less than 300 kg
a weight 300 kg to less than 500 kg
b weight 500 kg to less than 1,000 kg
c weight 1,000 kg to less than 1,750 kg
d weight 1,750 kg to less than 3,000 kg
e weight 3,000 kg to less than 6,000 kg
f weight 6,000 kg to less than 9,000 kg
g weight 9,000 kg to less than 12,000 kg
h weight 12,000 kg to less than 16,000 kg
i weight 16,000 kg to less than 20,000 kg
j weight 20,000 kg to less than 25,000 kg
k weight 25,000 kg to less than 35,000 kg
l weight 35,000 kg to less than 45,000 kg
m weight 45,000 kg to less than 60,000 kg
n weight 60,000 kg to less than 80,000 kg
o weight 80,000 kg to less than 100,000 kg
p weight 100,000 kg to less than 150,000 kg
q weight 150,000 kg to less than 200,000 kg
r weight 200,000 kg to less than 250,000 kg
s weight 250,000 kg to less than 300,000 kg
t weight 300,000 kg to less than 400,000 kg
u weight 400,000 kg to less than 500,000 kg
v weight 500,000 kg and greater
There are still Absolute Records but that is the domain of planes like the X-15 and SR-71. Way out of our league...