Last week United Air Lines took off with a preview flight of its Douglas DC-8 jet service to Hawaii. ... United now plans to fly the same jet from Honolulu to Chicago nonstop in less than eight hours. ... San hia#39; ai .ml Octubar 15. to IVlllMii wi -wwrtla lMri ttftirMr.l Ja| Ar3ifpaiAr w iliaa.lt in wm. on Pan Wa Polar Roov Id Kwrop- from the U ttagt;a| Coat* a lilt aquot;tit jHi on rha itratfh.1. I.. ... ford, Constantine aamp; Gardner, reports that seating will be doubled in August, when Boeing 707 jets go into service.