Traveller UPP designations

Starports:
A - current A/V
B - current B/IV
C - current C/III
D - current D/II
E - current E/I
G - Ground starport only (usual quality B-E)
H - Highport only (usual quality A-D)
P - Private (quality undetermined)
R - Restricted (Imperial facility, prison et al.)
S - redesignated F
T - redesignated G
U - redesignated H
X - No Port

Population:
X = No population observed (Law, Govt & TL will also be X)
N = Noble's Estate World
P = Prison Planet
T = Transient population

Government:
N = Administered by IN
S = Administered by IISS
M = Administered by Army/Marines
Q = Quarantine World

Law Level:
L = Martial Law imposed by Imperial occupation