United began service for the first time to Europe. Frankfurt was added to the schedule in June with Paris following in the year. Bermuda and Spain were added in the Spring of 1991. In the Summer of 1991, United came knocking at Pan Ams door again with the purchase of all of PA's Heathrow services for $290 million dollars. Also in the year, United place the first orders for the Boeing 777 and became the principal development partner.