SAME NIGHT OBSERVATIONS OF SPREAD-F BY THE JICAMARCA-RADIO-OBSERVATORY IN PERU AND CUPRI IN ALCANTARA, BRAZIL

50-MHz echoes from equatorial spread-F were observed on several nights by both the Jicamarca Radio Observatory (JRO) in Peru and the Cornell University Portable Radar Interferometer (CUPRI) in Alcantara, Brazil . Although little detailed correlation is expected between sites separ ated by such large distances, the night of October 17, 1994 shows some remarkable similarities between Peru and Brazil. On this night spread -F commenced at both Jicamarca and Alcantara as thin bottomside layers situated near 320 km altitude at nearly the same local times. Later, major plumes erupted that reached to over 1000 km altitude at both sit es. Since plumes normally drift west to east, these are obviously not the same structures but the similarities indicate that conditions for spawning them must have been coincidentally very similar on this night . The next two nights which produced plumes over Brazil, hut only bott omside layers over Peru, emphasize that local conditions on the same n ight can be very different at the two locations. The importance of hav ing a sufficiently wide beam for exploring spread-F over a large altit ude range at the Alcantara site is also explored.