Unfortunately, flight cancellations today are a part of air travel you can't always avoid. Airlines want all of their flights to depart and arrive on time, but things happen to cause delays. What should you do when you hear that your flight will be three hours late, or worse yet, is cancelled altogether? Here are some tips on dealing with flight cancellations and delays.

Weather delays aren't always a bad thing. When planes are grounded due to a thunderstorm, it is to ensure the safety of passengers and crew. You might not like being stuck at the airport for a few hours, but it is better than flying into a dangerous storm. 

As far as your rights in dealing with flight delays caused by weather, these issues are considered "acts of God." In general, the airlines do not have to offer you any compensation when your flight is delayed or cancelled due to a weather event. Sometimes an airline may choose to give some compensation, but this is generally not required, even if it entails an overnight stay.

Sometimes, flight delays today are caused by mechanical issues with an aircraft. Once again, this is a safety issue. If the airline determines there is any type of problem with the airplane, it is safer for passengers if they keep the plane on the ground until the problem is fixed. Mechanical problems can leave you dealing with flight delays of hours, or even days.

Equipment issues are not "acts of God," and so airlines typically offer passengers some compensation if there is a significant delay or an overnight stay required. The details of what they are required to do are spelled out in the "contract of carriage" that covers your airline ticket. Generally, the compensation offered is the same for each passenger on the plane.

Airline flight delays today can also be caused by crew issues. Sometimes the crew who are supposed to be on one flight were delayed coming in on another flight. Other times, this could be due to labor disputes. Like equipment delays, you will typically be offered some compensation if the delay is significant.

If an airline is offering compensation for flight delays, today that usually means you can get a voucher for food, frequent flier miles, or a travel voucher. If you need to stay overnight, the airline will usually offer a voucher that covers at least part of the cost of a hotel stay.

One way of dealing with flight cancellations is to try to avoid them. If you can see that a big winter storm is affecting one of your airports, try calling the airline in advance. Often, when airlines know they will have weather issues, they will waive the change fee so passengers can fly a different day.

When there are flight cancellations today, the scene at the airport can be chaotic, as hundreds of passengers all try to rebook on different flights and redo their connections. Sometimes you can get faster service by calling the airline than by standing in the crowd at the airport desk.