Rachel, your assumption was correct: 09:28 Feb 1
... these were Soviet personnel, indeed, namely «военные советники» who trained Babrak Karmal’s Army personnel and helped them plan and conduct operations. In addition to the regular units the Soviet military had then deployed in Afghanistan (ОКСВА, or Ограниченный контингент Советских войск в Афганистане, the then equivalent of today’s ISAF), it had «военные советники» assigned (or better yet “embedded”) to most units of the Afghan Army, police, and other security institutions.
Loyally translating them as “military advisors” would fly, I guess, but it’s too literal and English speakers rarely say so. If you want to be more idiomatic in English, you could go with “Soviet military trainers” (attached to Afghani units). | 
The translation workplace 
