NSA reports this aircraft went down on March 16, 1981. However, other sources report the aircraft went down on March 15. Two of the six killed were U.S. Air Force Cryptologists.

SSgt Steven C. Balcer, USAF
SSgt Harry L. Parsons, III, USAF 

On March 16, 1981, a U.S. Air Force RC-135 Cobra Bass II (#61-2664) was lost after returning from a reconnaissance mission off the Soviet Kamchatka peninsula.

The aircraft departed Eielson for Shemya with 24 souls onboard. While attempting to land, aircraft encountered a rapid decline in weather resulted in a crash landing. Six men lost their lives and several Medals were awarded for bravery.

rc-1351

This map shows the airport of departure and the intended destination of the flight. The line between the airports does not display the exact flight path.  Distance from Fairbanks-Eielson AFB, AK to Shemya AFB, AK as the crow flies is 1580 miles.

Sources:
aviation-safety.net
NSA.gov