I know UA codeshare with LH on the LAX-FRA route now, but I saw a picture of a UA 747sp and the person who took the picture said the plane was taking him back to Germany. After reading that I wanted to know how long did UA use there own planes on this route.
United operated Flight # 934 from Los Angeles via London/Heathrow to Frankfurt (1 Stop Service) from May 1991 till 1997 until the Star Alliance was born. This flight operated with an 747SP (later with an 747-400) ongoing an B-727 from LHR to FRA (later flown by an 767-200ER). There were many intra European Service offered by United from London/Heathrow as they took over many 727 from United.