This is a Trip Report from the Upper Class cabin
Ground Staff
Food & Drink
Entertainment
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Cabin Crew

Checked in efficiently within seconds, same with security and up to the clubhouse which, while not empty, was certainly not busy.
Thought I'd better book a haircut first, just in case (it was about midday, flight was 4pm). "When would you like it sir?" I was asked. "What's available?" I replied. "Name a time" they said. Fair enough!

Next - lunch and drinks: those Brambles really do slip down easily don't they? Is 5 too many?

Over the course of the next hour a couple of flights were called, after which I noticed I couldn't see any other passengers. So I took a quick walk round and counted just 4 people, including me. Wow, I thought, if only it were always like this! A quick chat to the waitress (who, I might add, was extremely attentive to the continuous requests for Brambles from her only customer!) revealed that 3 flights had been cancelled that day due to low demand, and mine was the next flight out in 3 hours. "Does that happen often?" I asked. "Never known it this quiet" she said. I was starting to feel rather lucky!

Anyway: those 4 hours in the clubhouse shot by - and a few more people did drift in as 4pm drew nearer. When the flight was eventually called I arrived at a deserted gate and quickly boarded through the front door.
So, what of the much talked about and, it seems, highly controversial A330 UCDS? I guess being in seat 1A gave me the advantage of having only one person next to me and as it wasn't anywhere near a full flight 1D opposite was empty right up to landing (more on that later). So in that respect I was lucky. It is definitely true to say the UC cabin feels very cramped compared to, say, the A zone of a 747. However I honestly didn't find the opaque windows on the dividers a problem: one of them's too far in front of you to really see your neighbour, and to see through the other way you more or less have to look behind you. So I didn't find privacy an issue - certainly much less of one than on the BA Club World seat where, when the cabin crew lower the window to serve food etc, you're face to face with your neighbour,
This being a short-ish day flight I didn't use the bed so can't comment on that but with the new, smaller ottoman my perception was that legroom wasn't as generous as in the classic UC seat (I'm 6'5" so that's important for me). I did like the storage compartment under the lid of the ottoman (which was big enough for my iPad, wallet and passport) but found the other storage pocket (where the magazines and safety card are kept) extremely difficult to access. The drink holder seemed flimsy and I noticed visible signs of wear and tear, as others have reported, which didn't seem good for such a new product.
The cabin crew were efficient and professional - I was addressed by name - but I didn't once see the FSM. I know the New York flights are relatively short but I do think they should offer a second food service, either tea or a light supper.
After getting over the shock of the captain telling us the temperature in New York was minus 5 but with the wind chill it would feel like minus 15 (and it did - I've never felt cold like that!), it was time to land. But not before a woman came and plonked herself in 1D, obviously hell bent on getting off first. She did, and walked even faster than me to immigration - only to make the schoolgirl error of not noticing that the shortest queue was for diplomats and crew only! She was promptly sent to the back of the next queue which by now had grown quite considerably. I, meanwhile, was through in less than 5 minutes as there was only the back end of another flight in the hall in front of us. Call it petty, but we all secretly enjoy little victories like that don't we!

Anyway, I should wrap up (I'm writing this, 3rd Redhead in hand, in the JFK CH waiting for my return flight). In summary - great LHR CH experience, good flight. No, the UCDS isn't perfect but I honestly don't get the people who say they'd avoid it at all costs. Maybe we've all been spoilt by the spaciousness of the 747s but it's still a perfectly good product.