Heathrow. Terminal 5. Day one; 3.20pm. We have been sitting on a plane for 1hr 40min, waiting for someone to come and let us out.

“It’s a complete and utter pigging shambles, ladies and gentlemen,” Captain Macaulay said over the aircraft Tannoy. “I have just wolf-whistled a passing member of our ground staff, who has put on his shining armour and is now going to connect the jetty. I can only apologise for this screw-up and dearly hope that you will give us another chance.”

That might be wishful thinking.

With British Airways’ big day in tatters, the passengers on my flight from Geneva aren’t happy: there’s the couple from Toronto, haranguing the captain about the cost of the taxi waiting for them; there’s the skier who had his appendix removed the previous night, clutching his side in pain; and there’s me.

I had flown out to Geneva on the 8.40am flight, and already things were starting to go wrong. Sitting in a stationary plane for the first, but not last, time that day, it was just like the old Heathrow we know and hate.

The bags were lost – all of them. Well, not actually lost, but not at the plane when they were supposed to be. The captain was magnanimous: “It seems some of our staff are unfamiliar with their new surroundings. Please bear with us.”

Before the actual process of flying anywhere had begun, everything had looked rosy. The terminal might lack the wow factor – after all, the Richard Rogers design dates from a competition held in 1989 – but the headline-grabbing shops and restaurants are pretty good. Security was working well when I passed through. And the champagne and eggs benedict at Gordon Ramsay’s Plane Food restaurant were delicious (they should be, at £21).

In fact, after walking around the terminal, I found little to fault. I sauntered into Paul Smith (where they will even sell you furniture for later home delivery), window-shopped at Tiffany and ogled the Sony centre. Trendy Spanish types refuelled at the juice bar, two young Argentinians mooched through Ted Baker, and I even saw a BA lady crouch down to ask a toddler how he was enjoying the vast bright spaces of T5, just like in an advert. But that was before everything unravelled.

There are plenty of other new airports doing vast and light these days – Hong Kong, Madrid, Bangkok, Beijing. What counts, in the long term, is not the swish and flash, but the nuts and bolts. Is your bag loaded on time? Does the jetty dock swiftly when you reach the gate?

The answer, based on the first day’s operation of the £4.3 billion Terminal 5, is: no. This mayhem needs fixing fast if BA’s gamble of moving almost all its flights into the one terminal is to come off. It’s a big ask, too: in a recent Skytrax survey of nearly 8m passengers, the airport came 103rd out of 162 in overall satisfaction, plummeting 58 places since the previous year thanks to last August’s lost-luggage horrors.

One thing they will never iron out is the location. This spanking new terminal is still at Heathrow. Once your plane leaves the jetty, you join the same queue for the same inadequate number of runways as you always did. Even without the luggage and staffing fiascos, it still took 25 minutes to taxi to the runway. It’s like a gleaming new wing has opened at a hospital that has come last in all the league tables for years. How would you feel about being admitted?

Oh, well, it is where it is. My flight to Geneva took off 90 minutes late; on the way back, I left the plane at 4.30pm instead of the scheduled 1pm. And after all that waiting, the bags weren’t at the carousel – just an army of staff handing out water bottles, biscuits and vague hopes of bags coming soon.

I was lucky: I had only carry-on luggage. By late afternoon, as I headed home, all luggage check-in had been suspended and the queues were from the dark old days. As the stewardess on the Geneva flight put it: “We were so looking forward to this working, and now our big day seems to have gone so wrong.” Quite.

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