State powers doctrine (see Amalgamated Society of Engineers v Adelaide Steamship Co Ltd). In this instance, the enactment of State laws will not serve to curtail any Commonwealth power; the Commonwealth's power is to be construed from the text of the Constitution. Section 51(i) permits the Commonwealth to make laws, for interstate and foreign air operations, about safety, regularity and efficiency, as this would protect, foster and encourage interstate and foreign trade and commerce. Barwick CJ stated that this would then serve to extend to include intrastate air navigation, due to intrinsic factors related to flight, and the factual situation in this case. Similarly, the Commonwealth licensing regime, which Barwick CJ held to be a "substantial safety procedure", can apply to intrastate air operations or operators because of the impact of unsafe, inefficient or irregular air operations by intrastate airline operators. Kitto J stated that the law is within power if it protects against physical interference by having regard to safety, regularity and efficiency; this is in contrast to matters merely consequential to interstate or foreign air navigation, which would not suffice. Regulation 200B Barwick CJ contrasted regulations 198 and 199(4) to regulation 200B. In the former, regulation of intrastate navigation was found to be in the Commonwealth's power to safeguard the safety of interstate and foreign air navigation. However, in the latter, the regulation purports to authorise the air operations themselves, as opposed to regulating the use of specified aircraft in those operations. The stimulation or authorisation of those operations that the regulation provides went beyond the regulation being a safety measure. See also Australian constitutional law References Winterton, G. et al. Australian federal constitutional law: commentary and materials, 1999. LBC Information Services, Sydney. High Court of Australia cases 1965 in Australian law Australian constitutional law Trade and commerce power in the Australian Constitution cases 1965 in case law