R-Second

R-Second is an Autobot drone from the Wings Universe portion of the Generation 1 continuity family.

R-Second was Sentinel Major's personal drone, following R-First and followed by R-Third.

Fiction

Wings Universe

Wings Universe is based on the Generation 1 cartoon, but deviates from it in cosmetic ways and continuity points.

R-Second apparently displeased Sentinel Major enough that he replaced it with R-Third. A Team Effort