There are many things that can make it impossible for flights to arrive on time. Some of these problems, such as bad weather and resulting air traffic delays, are beyond the airlines control. Others, such as the need for mechanical repairs, cannot be predicted. Nevertheless, you can take steps to reduce your chances of encountering most problems and limit their effects.
When booking your flight, remember that a departure early in the day is less likely to be delayed than a later flight, due in part to the ripple effects of delays throughout the day. Also, if an early flight does get delayed or canceled, you may have more rerouting options. If you book the last flight of the day and it is canceled, you could get stuck overnight.
In general, you are least likely to be delayed on nonstop flights. A connection (change of planes) always involves the possibility of a misconnection. On a direct flight (intermediate stop, no change of planes), the second leg could be delayed or canceled. If you choose a flight with a stop or connection, try to select one stopping at the least-congested enroute airport in order to reduce the risk of delay or misconnection.
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