None of the below will do what it says it will yet. air-ng is in version 0, and the first usable release, v1, is being worked towards - you can see the progress here.
The documentation below is meant to show the intention for the API's final structure.
air-ng itself can be installed the usual way:
$ npm install air-ng
However, the calls require various parts of the aircrack-ng suite to be installed and accessible from your path. The recommended environment to run any application relying on air-ng is a machine running Kali either as a natively-installed OS or a virtual machine with full access to an external network card. Kali comes pre-installed with the entire aircrack-ng suite.
var air = ;// airodump-ngvar airodumper = air;airodumper;// aircrack-ngvar aircracker = air;aircracker;aircracker;