The Bristol Type 175 Britannia was a Britsh medium/long-range airliner built by the Bristol Aeroplane Company in 1952 to fly across the British Empire. Soon after production the turboprop engines proved susceptible to inlet icing and two prototypes were lost while solutions were found. By the time it was cleared, jets from France, UK and the US were about to enter service and only 85 Britannias were built before production ended in 1960. Nevertheless the Britannia is considered the high point in turboprop design and was popular with passengers, earning itself the nickname "the whispering giant" for its quiet and smooth flying. Source: WIKIPEDIA