This page gives a summary of the correspondences between the ED-99/DO-272 features, the AIXM 5.1.1 features. and the AIRM 1.0.0. More details on the correspondences and encoding support are available by clicking on the relevant ED-99/DO-272 feature. The table also contains links to the AIXM and AIRM websites.
The xml file containing all required features is available here.