Talk:Type 0 Fighter Model 21/@comment-26875340-20161226123558/@comment-460323-20161226124252

Double chevron will suffice.

However, since improvement level carries over to the next plane, it's strongly recommended that you max improve them before completing the quest. Model 21 (Skilled) requires more Model 21 planes to max (relative to plain Model 21) whereas Model 52 (Skilled) requires more screws.