What date was the winner the new york jets and a Result of 30–28?
CREATE TABLE "1970s_jets_12_8" (
  "year" real,
  "date" text,
  "winner" text,
  "result" text,
  "loser" text,
  "location" text
);
SELECT "date" FROM "1970s_jets_12_8" WHERE "winner"='new york jets' AND "result"='30–28';