CREATE TABLE table_31637 ("Aircraft" TEXT, "Origin" TEXT, "Type" TEXT, "Versions" TEXT, "In service" TEXT)

What aircraft type is the Casa C-212 Aviocar?
SELECT "Type" FROM table_31637 WHERE "Aircraft" = 'casa c-212 aviocar'
SELECT "Type" FROM "table_31637" WHERE "Aircraft" = 'casa c-212 aviocar'