Originally Posted by
rog747
Thanks - Sadly what was the Achilles heal of the -200SUD conversions, and also the 300 series, was that the upper deck floor was not strong enough for the new wave of big heavy electric F/J/C Class seats that were becoming de rigueur with all the legacy airlines - The seats simply were too heavy for the UD floor plus channelling the electrics posed issues.
The upper deck was of course more popular for F and J/C seats therefore the resale and re-use values of these two somewhat ''orphan fleets'' was not very good.
The -400 did not suffer from this UD floor issue.
About 1975, I had a delightful flight from Vancouver to Honolulu on the upper deck of a CP Air 747-200B. It was outfitted with about 28 economy seats, used when the main deck was fully booked. We were not allowed down the spiral staircase, which went into the first class cabin, but the flight deck door was open all the time and we had our own attendant, who was quite concerned and needed an explanation when I presented a very heavy woollen coat to be hung in the closet ... she was thinking of Siberia rather than Mauna Kea! The view out of the windows was spectacular, and it was an oddly cosy and intimate way to cross the ocean in such a huge aircraft, whose wings and engines on both sides were so visible from that cabin. For me, the 747 was usually attractive because one could take long walks through its cabin, broken up into relatively small sections by all the central galley and toilet blocks.