|Start:||March 4, 1987 ||Observed|
|Stop:||March 18, 1987 ||Observed|
|Flank eruption: ||
|Central eruption: ||
|"Fire", "Glowing", or incandescence: ||
|MaxVEI: ||2 ||
|ColHeight: ||3600 m ||
From Smithsonian Institution (1987): "On 18 March at 1954 a NOAA 10 satellite image showed three distinct plumes, each 95 km long, drifting ENE. The estimated vent locations were: 52.38°N, 174.15°W (Korovin's summit); 52.31°N, 174.24°W; and 52.29°N, 174.21°W (5.5 km WSW and 6.5 km SW of Mt. Kliuchef, a cone on Korovin's S flank). More accurate locations will be determined by USGS Anchorage. Just before midnight on the same day US Navy pilot Jeffrey Sullivan observed a southward-drifting ash plume rising to at least 3,000 m altitude, lit by an orange "flame" from Korovin. Smaller orange flickering "flames" from two other vents at lower elevation were visible. Two of the vents were ~2 km apart and the third vent was ~10 km NE of the other two vents.
Earlier in the day (at 1300) Julie Dirks and other Atka residents noticed sulfur smells (~18 km from the volcano). Although the weather was clear Dirks did not notice any "unusual" eruptive activity. On 19 March a SIGMET notice was issued to warn pilots of volcanic ash 185 km on either side of a line from 52°N, 175°W to 54°N, 172°W. The warning remained in effect until 0930. Pilots reported that the ash cloud reached 3,600 m."
Additional information from Reeder (1990, Kliuchef): "Lieutenant Jeffrey Sullivan flying his U.S. Navy P3 Electra from Dutch Harbor to Adak at a 8,200 m altitude, noted about 240 km E of Adak just before midnight on 18 March a large orange flame with smoke to the south that was determined from the satellite imagery to be from Korovin volcano. Then, about 5 minutes later, Jeffrey could see two more smaller orange flickering flames that were farther to the south and were at a lower elevation than the first flame. These lower and smaller two flames would have been the two Mount Kliuchef SW flank vents."