Even though air travel is as normal in the U.S. as taking a cab, many people suffer from fear of flying. However, the chances of being hurt on a scheduled airline trip are less than by taking a car, bus, train or taxi.

The Anxiety and Depression Association of America has good tips for overcoming one’s problems associated with flying, along with medical help links. Among the good advice on the group’s website, adaa.org, is “know the facts,” and that’s where science can help.

Airline pilots try to make every flight comfortable by avoiding altitudes where the air is “rough.” Nobody wants their coffee bouncing out of the cup, but for some, turbulence triggers a fear that the plane might crash. The fact is that at cruising altitude, the plane is almost 7 miles (39,000 feet) above the ground.

If an updraft or downdraft pushes it up or down 100 feet, it will feel threatening to some passengers. But that’s a tiny amount compared to all the air space below the plane. Just like there are potholes on some highways, the atmosphere has spots where the flow is highly uneven. A thumpy ride can be annoying, but it’s not something to be feared.

When you look out the cabin window, you can see the wing flexing, or even flopping up and down a lot. Nothing is wrong with that. If aircraft wings were hard, they’d be liable to break. Think of a sailboat. Its sails aren’t hard sheets of steel. They are soft in order to adjust to the quirks of the air that’s hitting them.

Scary movies like to show oxygen masks dropping down in front of terrified passengers, seconds before a spectacular crash. But it means simply that the cabin is losing air pressure for some reason. Seven miles above the ground, the air is too thin to breathe. After all, we’re up higher than the world’s tallest mountain, Mount Everest, which is 29,029 feet.

The plane has artificial air pressure. If that system fails, or a leak develops, the masks ensure people can keep breathing. It won’t make the plane crash. The pilot will simply descend to lower altitude, into the higher air pressure that we’re used to.

Just know that at any time, there are 5,000 to 7,000 flights in the air, and the odds of a safe arrival are overwhelmingly good.