My school (Townfield in Hayes) did a visit to London Airport and we went through "Canopus" before the Queen went on her trip.
Perhaps it was a regular sort of trip.
I too went on a school trip and seem to recall being amazed at the down stairs lounge area.
IIRC there was a panel down there to give access to manually lower the undercarriage.
We also visited a TWA Connie - Star of ....