Two new notams affecting U.S. entry and overflight requirements went into effect last month. Notam 8/3576 covers U.S.-registered aircraft with an mtow of 100,309 pounds or less. These aircraft will not require an airspace waiver, as long as all applicable conditions outlined in the notam are met. Notam 8/3577 requires U.S.-registered aircraft with mtows exceeding 100,309 pounds to obtain a TSA waiver or be authorized under an approved TSA aviation security program when operating to, from or overflying U.S. airspace.