Yes, you used to be able to go there for a visit. The tops of the 'fingers' were 'viewing areas', two bob (10p) to get in. I've got a quantity of 35mm slides lurking in the loft! There was even a restaurant where you could enjoy late night views of the apron! I used to clean aircraft interiors as a student summer job in the late 60's. It was never the same after the PLA hijacked some planes.....I later did a spell with the BAA in the 70's, before returning once again to work with a car rental co. in the late 80's. I left there in '94, and it's changed since then!