Boeing Stratocruiser:
For me, the Stratocruiser epitomised the imagined sophistication of airline travel in 1951, when I first saw BOAC's silver beauties at Heathrow on a school visit. Double-decked, with a spiral staircase leading to a passenger lounge, and an impressively bulbous fuselage with high panoramic flight deck. Alas, by the time I was old enough to fly they were all gone.
Years later, flying BA Club World on business to Bahrain, I got a strong sense of 'deja-vu' boarding up the spiral staircase to the upper deck of the 747. Even better, this being well before 9/11, I asked for and got a flight deck visit. While chatting to the flight crew, the F/O pointed out the scheduled BA aircraft en route back to Heathrow, a couple of thousand feet below over Saudi. My childhood imaginations of what it must have been like on the Stratocruiser's "bridge" were strongly evoked.