Author: John Cox, Special to USA TODAY

Runway length is carefully calculated before every takeoff and landing.

With modern airplanes and well-trained pilots and ground staff, we fly safely in challenging conditions every winter.

Ferry flights often use remote airfields for refueling. For the North Atlantic, flights may include fuel stops in Canada, Greenland and Iceland.

The Digital Flight Data and Cockpit Voice recorders have proven to be very successful over the decades.

Airlines flew nearly 4.5 billion passengers on nearly 45 million flights worldwide, both records. But there were 15 accidents worldwide.

Pilots fly many different airplanes of the same model within a fleet. While there are some differences, they fly pretty much the same.

Modern airplanes are designed to withstand heavy turbulence without damage.

The A380, the largest airplane in commercial airline service, can hold nearly 86,000 US gallons of jet fuel.

Flight crews face challenges balancing safety and compassion when passengers bring animals on board for emotional support.

The B757 is a high-performance airliner. It operates well in high-altitude airports and is one of Boeing’s best performers.