The authoritative Scott's Catalog (Scott 2007 Us Specialized Catalogue of United States Stamps & Covers (Scott Specialized Catalogue of United States Stamps)) will consider a stamp an AIR MAIL stamp if it has those words on it, or if it has an aircraft "icon" on the stamp. We thus have a new generation of airmail stamps, in answer to a page earlier.
There are some differences. These NEW GENERATION stamps are self-adhesive, you can see the differences in the die-cut "perforations." Nevertheless, U.S. Airmail stamps are not extinct, and that is big news for those who enjoy collecting them.
© 2001, Justin Milliun, All Rights Reserved.