The ICAO designator for all airports in the contiguous US starts with K, so it’s full designator is KLAX. Same for KPDX.
There are over 5,000 public use airports in the US. While not all of them start with K (some very small airports start with a number instead), all moderately sized or larger airports do.
Speaking of which, why is Los Angeles International Airport LAX, and not LAI or LAA?
X means international I think
X is from when airport codes were two letters.
The ICAO designator for all airports in the contiguous US starts with K, so it’s full designator is KLAX. Same for KPDX.
There are over 5,000 public use airports in the US. While not all of them start with K (some very small airports start with a number instead), all moderately sized or larger airports do.