Indian and European hubs crowd the list.

Planning to visit India or Europe? Budget extra travel time. If airport delays in 2008 are any indication, you'll need it.

India takes the prize as the country with the most frequent late arrivals in our second annual tallying of the world's most-delayed airports. For departures, European airports -- notably those in Italy -- make up the bulk of the worst, though Beijing Capital Airport grabs the top spot.

India is a peculiar case. Its biggest airports have undertaken massive construction projects to cope with the country's rapid growth. Our most-delayed airport, Mumbai's Chhatrapati Shivaji International, opened a new taxiway in November to reduce the wait time for landing aircraft.

Good thing -- only 50 per cent of its flights arrived on time in 2008, according to FlightStats, a service that tracks historical and real-time flight information.

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New Delhi's Indira Gandhi International Airport, with a 51 per cent on-time arrival percentage last year, fully opened a third runway in October.

In May, Bangalore saw the addition of a sleek new airport, Bengaluru International, where growing pains account for some of the arrival delays. The airports ranked second and fourth on the list of worst arrivals, respectively.

In India, delayed arrivals are largely attributed to air congestion at a flight's origin, says a spokesperson for Bengaluru International Airport Limited, which owns and operates the city's new airport.

There, 80 per cent of departures were on time in 2008, yet just 60 per cent of flights arrived as scheduled. Why the difference? Faster runway exits and improved efficiency at the new airport give a boost to the percentage of flights departing on time.

Also high on the list of airports with the lowest percentage of on-time arrivals: Casablanca's Mohammed V International Airport (54 per cent on time); Orio al Serio Airport near Bergamo, Italy (61 per cent); New York LaGuardia (62 per cent); Newark Liberty International (62 per cent); Birmingham Airport in England (63 per cent); London's Luton and Heathrow Airports (both 63 per cent on time).

According to Kyla Evans, a spokeswoman for Eurocontrol, the Brussels-based air navigation safety organization, airspace and taxiway congestion are the main cause for delays in Europe.

Seems logical, given the high number of European airports with delayed departures. They include: Manchester Airport in northern England (49 per cent on time); Venice's Marco Polo International (54 per cent); Nice Côte d'Azur International (56 per cent); Rome's Fiumicino International (58 per cent); and Paris's Charles Orio al Serio, near Bergamo (59 per cent); Athens International (61 per cent); and Paris's Charles DeGaulle International (62 per cent on-time).

Officials from several European airports did not respond to requests for comment. Nor did those from Beijing Capital International, which was the hub for Olympic air traffic in August.

Compiling a list of the world's most-delayed airports is no easy task. Geneva-based Airports Council International (ACI) doesn't track arrival and departure information. Thus, we again asked FlightStats, operated by Conducive Technology Corp. in Portland, Oregon, to pull on-time information for the world's busiest 200 airports, as determined by ACI.

FlightStats gets its information from airlines, airports, flight reservation systems and other sources. For information about U.S. airports, we cross-checked the company's data with information published by the U.S. Bureau of Transportation Statistics.

Our list this year looks slightly different from last year's because we examined only those airports about which FlightStats has the most detailed information. Notably, we omitted some airports in South America from consideration.

One constant: The world's least-delayed airports are concentrated in Japan and Korea. Of the world's 200 busiest airports, not a single one in Japan or Korea has an on-time percentage below 82 per cent, arrivals and departures included.

In Pictures: The World's Most-Delayed Airports

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