The 1990 Gulfstream IV executive jet owned by David Copley's once-proud Copley Newspaper chain, which is still trying to unload the Union-Tribune, is on the block. The luxurious aircraft — used by Copley to transport himself back and forth to New York shows and vacations in the Mediterranean and Caribbean on his $30 million yacht Happy Days — is being advertised on the Internet by Bloomer deVere Group Avia, Inc., a Camarillo-based airplane broker. Would-be buyers are advised to “make offer”; similar models go for around $20 million. G-IVs can carry up to 20 passengers in standard configuration, but the Copley plane is outfitted for just 12, according to a description of the interior. The plane features spacious galleys forward and aft, both with microwave ovens. The “Airshow 400” information center includes a 20-inch TV up front and a 12-inch screen in back. There is an RCA VCR player and a DVD player with an iPod jack, along with a Sony ten-CD changer. The craft also comes with a Tempus Med-Alert system with portable patient monitor, presumably installed for Copley, who has had a heart transplant.