Why Don’t Airplanes Fly Over Tibet and Antarctica?

Tibet​

As you know, modern aviation has almost no limits. However, there are still areas that pilots prefer to avoid. One such place is Tibet. This region in Central Asia is home to the world’s highest plateau, with much of its land sitting at least 13,000 feet (4,000 meters) above sea level.

The Tibetan Plateau is covered by vast mountain ranges. To the north, the Kunlun Mountains stretch across the region, while the Tangla Mountains cut through Tibet, and to the south, the towering Himalayas form a natural border. Out of the world’s fourteen tallest mountains, nine are located in the Himalayas. This extreme geography makes Tibetan airspace difficult to navigate for most commercial aircraft.

Technically, flying over the Himalayas is not forbidden. Airlines can obtain special permits from Chinese authorities. However, this is not a simple process, as it requires modifications to aircraft systems—particularly upgrading onboard oxygen equipment. But why do Chinese authorities demand this?

Safety Comes First​

The main reason is passenger safety. Modern passenger jets typically cruise at altitudes of 33,000–39,000 feet (10–12 kilometers), and this isn’t just for the scenic views. At these heights, air resistance is much lower, allowing the aircraft to achieve optimal cruising speeds efficiently.

However, reduced air resistance also means thinner air, leading to lower oxygen levels. If you were exposed to the outside air at these altitudes, you would lose consciousness within 15 seconds due to oxygen deprivation.

This is why airplanes are equipped with emergency oxygen masks. In the event of cabin depressurization, these masks supply passengers with oxygen for approximately 20 minutes. Aviation safety regulations assume that this amount of time is sufficient for pilots to descend the aircraft to a safe altitude of 6,500–9,800 feet (2–3 kilometers), where passengers can breathe without assistance.

In a crisis, descending over Tibet’s mountainous terrain would be nearly impossible. Pilots would need to fly at least 300 miles (500 kilometers) before finding a suitable area to drop altitude safely. Given these conditions, 20 minutes of emergency oxygen is far from enough. This is why China enforces such strict regulations for flights over Tibet.

There’s also another technical concern: the small margin between the aircraft’s cruising altitude and the towering peaks of Tibet increases the likelihood of turbulence. While turbulence itself doesn’t pose a major safety threat to modern passenger aircraft, no one enjoys a bumpy flight.

For airlines, it’s simply easier to adjust their flight paths and avoid Tibet rather than investing in expensive modifications and dealing with regulatory approvals. This is the standard approach worldwide.

Antarctica​

Another region where passenger jets are rarely seen is Antarctica. There are several reasons for this.

First, Antarctica has very few runways. The entire continent has only three airstrips, mainly used for research expeditions. These runways do not operate regularly and depend heavily on weather conditions. Under such circumstances, it would be highly unsafe for commercial airlines to schedule regular flights over Antarctica.

However, the primary reason is not a lack of infrastructure. The reality is that flying over Antarctica simply isn’t commercially viable. Due to the geographical layout of the Southern Hemisphere, there are very few flight routes that would require crossing the South Pole.

Even if we were to draw a direct line from the southernmost tip of South America to Australia or New Zealand, the route would pass only over the northern edges of Antarctica. Flying directly over the continent would unnecessarily extend the journey, making it economically unfeasible for airlines.