(3)
 Between places in the same possession of the United States;

Whether that commerce moves wholly by aircraft or partially by aircraft and partly by other forms of transportation.”
intertropical convergence zone (meteorology). The boundary zone between the trade wind system of the northern and southern hemispheres. It is characterized in maritime climates by showery precipitation, with cumulonimbus clouds sometimes extending to great heights.
intrastate air transportation. 14 CFR Part 1: “The carriage of persons or property as a common carrier for compensation or hire, by turbojet-powered aircraft capable of carrying thirty or more persons, wholly within the same state of the United States.”
Invar. The registered trade name for an alloy of 63.8% iron, 36% nickel, and 0.2% carbon. Invar has a high relative resistance and a very low coefficient of thermal expansion. Invar is used for wire-wound resistors.
inverse peak voltage. The peak, or maximum, voltage applied across a rectifier during the half cycle of alternating current when the rectifier is not conducting.