CREATE TABLE "complete_formula_one_world_championship_" (
  "year" real,
  "entrant" text,
  "chassis" text,
  "engine" text,
  "points" real
);

Question: Which year did Ray Crawford the Kurtis Kraft 500g chassis?
SQL: SELECT "year" FROM "complete_formula_one_world_championship_" WHERE "chassis"='kurtis kraft 500g';