More than affecting the plane itself, abnormal or acute weather conditions can cause severe disruptions to airport efficiency and procedures. The main dangers are possible disruptions with communication services and dangerous conditions for landing a plane, such as heavy winds or rain and severe snowstorms. One such instance was the Icelandic volcanic eruptions that halted flight services for most of Europe in 2010. The eruptions bought the continent to a complete standstill, and many travelers spent their vacations inside airports. To combat this, airports use highly advanced weather detection services to assess flight safety well in advance. They also have specialist weather teams to handle runway conditions. The Federal Aviation Administration publishes flight weather warnings to pre-warn customers of cancellations.
Deep vein thrombosis, or DVT, is a condition where a blood clot, known as a thrombus, forms in one or more of the deeper veins in your body. Deep vein thrombosis doesn't always cause pain and often occurs without any symptoms. Traveling by plane can significantly affect your likelihood of getting DVT because you are sitting still for such a long time without any opportunity to stretch your legs or move around. Flying economy class is particularly dangerous because leg room is so small and confined, and stretches and movement, which are vital for maintaining blood flow, are difficult. DVT usually clears up on its own, but some cases can lead to clots traveling to the lungs, according to the Mayo Clinic.
The air recycled in an airplane during flight can be a breeding ground for sickness. Tuberculosis, for example, can be contracted through the cabin's recycled air, and other illnesses like the common cold and flu can be passed on to passengers. Because the air is recycled, passengers don't need to be sitting next to each other to contract a disease. Air is recycled because pumping fresh air into a cabin is expensive, and airlines use cooling packs to recycle air and cut costs.
Ever since the 9/11 attacks on New York's World Trade Center and the Pentagon in 2001, terrorism has been a continuing threat to airlines across the world. The dangers in particular are hijackings or explosions on planes. The potential for loss of life is extremely high --- approximately 3,000 people were killed in the 9/11 attacks --- so airlines have imposed rigorous and tight security measures to prevent dangerous individuals from getting onto planes. The most effective measure used to prevent attacks are security scanners, which detect explosive devices and dangerous weapons and are installed along several points, from check-in to boarding.
