A Crash Landing.(World Affairs)(Heathrow Airport's Terminal 5)

Byline: Rod Nordland and William Underhill; With Sophie Grove and Christopher Werth in London

Heathrow is one of the world's busiest airports--and possibly the worst.

Heathrow is hard to avoid. The world's busiest international airport is also its most crowded. Every year some 67 million passengers--up to 200,000 a day--pass through the airport's four terminals, which were designed for 45 million people. The airport operates at 99 percent capacity, and with only two runways, 65 percent of its flights are more than 15 minutes late. According to a report last year, Heathrow's major carrier, British Airways, ranked 24 out of 25 European airlines for its record on lost baggage. Some 2 million business-class and first-class passengers have abandoned Heathrow since 2006. A survey of leading figures in the aviation business last year rated Heathrow as the worst of the world's leading airports.

But all that was supposed to change last week when Heathrow's grand Terminal 5, dedicated to British Airways flights, opened to its first passengers. The biggest freestanding building in Britain, it was designed to end the interminable queues for security and check-in, and whisk passengers through the formalities in a promised 10 minutes. State-of-the-art security systems would make it convenient and safe. Underground baggage conveyors would ease the conveyor congestion for which the airport is justly infamous.

Instead, just about everything that could go wrong, did--short of an airplane crash. Passengers were stuck for up to 20 minutes in elevators, which often stopped working altogether. By day two, only one out of a bank of 15 elevators worked, leaving airport workers to carry wheelchair-bound customers up stairs. The monorails meant to zip passengers to satellite boarding areas failed completely. Only 20 percent of scheduled flights were flying. On incoming flights, luggage disappeared without a trace. "Heathrow has been an international disgrace for years, and this was meant to be a new beginning," said British interior designer Howard Pike, who arrived from Oslo the first night and was still looking for his bags the next day. "I've always avoided Heathrow, and now I'm going to avoid it even more."

BA did its best at damage control. Workers donned yellow T shirts reading CAN I HELP? and fanned out through the legions of stranded and delayed travelers. But in the words of David Wilshire, a Conservative M.P. whose constituency includes Heathrow, "It couldn't have been worse." In a way, BA and the British Airports Authority were victims of their own public relations. The opening followed a lengthy campaign that culminated in a ceremonial opening by the queen two weeks ago, which went off without a hitch. Expectations were high that a terminal building big enough to handle 30 million passengers a year on its own would soon bring an end to the human traffic jams and other indignities suffered by travelers to London. The airline and the airport operator--which also runs London's Gatwick and Stansted airports--suggested the other was to blame, Wilshire says. But the real problem is that it was the biggest airport restructuring "anywhere on the planet."

The opening of Terminal 5 may be just the ...