The most recent threat nearly got away. The 30-year-old Pakistani American was on board this flight, bound for Dubai when pilots heard this from Air Traffic Control: Federal agents stopped the flight and removed Shahzad, who managed to board the airplane despite being placed on a "no-fly" list hours before.

VOA: standard.2010.05.06

More than three billion people are at risk from indoor air pollution because of the heating or cooking fuels they use.

VOA: special.2010.02.01

When his head came out of the water for air, he saw that he was farther away from the soldiers.

VOA: special.2011.05.28

Untreated patients can spread the bacteria from their nose and mouth through the air to people who are near them a lot.

VOA: special.2009.10.14

Rinderpest can spread quickly through the air and in water containing waste from animals with the virus.

VOA: special.2010.11.02

They were suspended from ropes as they used heavy air-powered hammers to break any loose rock away from the face of the canyon walls.

VOA: special.2009.08.12

Ocean storms develop when the air temperature in one area is different from the temperature nearby.

VOA: special.2010.08.24

The shape of a snow crystal may change from one form to another as the crystal passes through levels of air with different temperatures.

VOA: special.2010.01.05

Cold weather moves south and combines with the last of the warm air from summer.

VOA: special.2009.06.09

Engineers on the ground designed a way the astronauts could connect air-cleaning devices from the command module to the air system in the lunar module.

VOA: special.2009.07.22

Fire from the natural gas well shot about one hundred forty meters into the air.

VOA: special.2009.03.22

Pictures taken from the air after the tsunami also showed a shocking loss of land.

VOA: special.2009.03.17

You can rent an aircraft and take photographs of the beautiful Keys from the air.

VOA: special.2010.03.22

We asked competitor Chuck Mung from Portland,Oregon why he thinks air guitar is so popular.

VOA: special.2009.08.14

Electromagnetic waves or energy passed through the air from one device to the other.

VOA: special.2010.12.08

A tornado is a violently turning tube of air suspended from a thick cloud.

VOA: special.2009.06.09

During spring, warm air moves north and mixes with cold air remaining from winter.

VOA: special.2009.06.09

Warm air rising from below causes the wind tube to reach toward the ground.

VOA: special.2010.05.11

She remembered how the white heron came flying through the golden air and how they watched the sun rise together from the top of the world.

VOA: special.2010.04.03

From high in the air, visitors can clearly see the third area of the park -- a high broad flat rock known as the Island in the Sky.

VOA: special.2009.04.15

But Mister Swayze notes limits on the asbestos searches from the air.

VOA: special.2009.11.17

The devices are designed to remove dangerous particles from the air.

VOA: special.2009.07.14

They would gather small amounts of air from the upper atmosphere.

VOA: special.2010.05.26

The astronauts had removed all air pressure from the spacecraft.

VOA: special.2009.06.24

The first HEPA filters removed radioactive particles from the air.

VOA: special.2009.07.14

"We're so much more visible from the air than we are from the ground that maybe we can be a deterrent,"

VOA: standard.2010.01.01

Among them was Retired Air Force General Michael Hayden, who held the post from 2006 until early this year.

VOA: standard.2009.04.20