When I was younger and less informed than now (which means totally un-informed as opposed to marginally informed), I always thought the upper deck on a 747 was for first class seating.

Now it seems that first is always in the nose and business is in the upper deck.

Is this always the case for all airlines?
Has it always been that way?

LH First is still upstairs.

I think it varies from airline to airline. I was surprised the first time I flew a 747 because i always thought that there were lounges up there. I'm told that was waaay back in the day.

This changed with the stretched upper deck 747 (-300/-400), as:

- the original upper deck was too small to accommodate anything but a lounge or first class

- the current stairs at door 2 are probably perceived as too far back for 1st class by most airlines

I do not know if some airlines still use the upper deck for F. On the airlines I fly no.

In the 70's, the upperdeck as well as the front of the plane was F.
Swissair for example had its seats downstairs and a lounge upstairs with bar and and large array of food to pick on.
One was able to smoke, too... That was flying. The seats were less comfortable but the walking up and down was good for exercise.

Pan Am even had a "table restaurant" and one was served exactly as in a real one.

Philippine Airlines, if I recall rightly, had little bedrooms with pyjamas, etc.

Soon the airlines realized that they were loosing a lot of revenue by not selling the space available for seats. So, very fast, all this luxury disappeared.

I believe VS combine Premium Economy and Upper Class (the equivalent of Business Class) on the Upper Deck, though VS flyers correct me if I am wrong as I have never flown VS

IB also has F upstairs. Most airlines find the upstairs to be too cramped, hence the F in the nose (this is certainly true if wanting to offer suite seating, as the market expects for long-distance F).

I have flown the following in a 747 F cabin.

LH F upstairs
UA F in nose
QF F in nose

Note to self: fly more award intl F!

It really depends thru which door of the aircraft you board/disembark. The stairs are not too far back. To me the upper deck is, despite the shape and relatively small size, always nice to fly on. It has a certain feeling of being above the rest. Almost private jet atmosphere with the pilot in the front.

In the early 90's I flew on a SwissAir 747 from JFK-Zurich. Amazingly, their upper deck was coach and that was the only time I had a seat up there!

Which is why I always prefer J on Upper Deck to main deck. Better service (usually as its quieter. I think checkin agents fill the main deck first), less queue for the loo and the 2-2 layout

PE upstairs is a fantastic way to fly without paying top dollar. The legroom is not fantastic, but the privacy and quietness of the cabin are excellent.

Same here, on a BOS-ZRH flight in the mid-80's. Checking in, the agent said, "Would you like to sit upstairs?" Heck yeah! I felt a little bait-and-switched when I discovered it was still a coach seat.

I think LHR Virgin planes combine UC and PE and LGW planes are all PE on the upper deck.

I remember seeing some old BA 747-200 seat maps from the Paper Timestable Circa 1996 which actually had 3x3 economy seats in the bubble.

When the 747 first came out there were only two classes, F and Y. The "standard" configuration at that time was not to have any saleable seats on the upper deck but to arrange it as a dining lounge/bar etc for the F passengers. The main deck typically was laid out about F55 Y310. On the 747 Classic the upper area was much smaller than the longer type introduced on the 747-300; indeed the early 747s only had 3 windows on each side. The only reason for the "hump" initially on 747s was to put the flight deck over the nose cargo door that was in the original military freighter design. Many propeller military freighters had done the same thing.

There were some early 747s with charter companies that were Y class throughout; airlines such as Condor (Germany) and Wardair (Canada) operated them, with 3+3 seating up top.

There is a problem with having a seat class only available on the upper deck (eg all the F seats up there) that disabled travellers in that class would not be able to access it. This is why you need all classes to have some seats on the main deck.