The Vaisala CORA Automatic Sounding System was introduced in the early ’70’s, here pictured with a manual sounding system (on the left).

The RS18 and RS21 Radiosondes that were in production in 1973-81 represent the third generation of Vaisala Radiosondes. The RS18 operated on the 25 MHz frequency, which was the standard operating frequency of the old Väisälä sounding system. However, the 400.05 - 406 MHz frequency was allocated to international meteorological use in 1959. The RS21 operating on the 400 MHz frequency band was developed to meet this new requirement.

A third-generation Vaisala Radiosonde, RS21, being launched.

Vaisala participated in the international GATE (GARP Atlantic Tropical Experiment) program and FGGE (First GARP Global Experiment) project in the '70's. The main objective was to obtain reliable observation data from all over the world. Pictured a FGGE project just off Sydney, Australia.

The first Vaisala airport weather system was delivered in 1975.