Russian Aviation Museum

As many aircraft designers, Sergey Ilyushin started with gliders... The 'Rabfak' means exactly 'Workers department' and was nothing but a special department in the University or other research/educational institution created specially to improve
educational level of working people, as well as to prepare enough specialists to compensate losses during Revolution, Civil War and repressions.

So name 'Rabfakovets' stays for the student of 'Rabfak'.