Great Circle Routes: How Are Current Wars Affecting Aeronautical Traffic?

Image Credit: JFK Photography via Pixabay

Mony Aramalla explores the concept of great circle routes and how the war environment affects the airspaces around the world.

If you look out of an aeroplane window when you fly from Dublin to New York, you would see Greenland when expecting to see the transatlantic ocean. The Middle Eastern airports in Dubai, Abu Dhabi, and Qatar are known as global aeronautical hubs for a strong reason. There is mathematical reasoning behind why Finnair, the Finnish Airline, is a common connecting flight for those travelling between Europe and China. 

On a map, it may look like a straight line-distance between two points has to logically be the shortest route. However, the Earth is nearly spherical. Primarily elliptical and the Great Circle route is the shortest course between two points on the planet. Mathematicians knew the calculations behind this technique before the Age of Exploration. However, it was never used as a navigation mechanism. Before the 19th century, sailors used to sail along Rhumb lines, or straight lines from one point to another. Fully dependent on the wind currents to dictate their path, sailors stuck with the Rhumb lines which made it much easier for them to follow. The Industrial Revolution brought the development of steam engines and soon, The Great Circle navigation system was adopted. A culmination of the invention of steam engines and the application of mathematical knowledge, sailors were no longer obligated to follow the geometrically straight routes. Steam-powered engines were used to propel the ships in the desired direction, with no dependence on the wind, allowing sailors to follow the curvature of the planet to make use of these shorter routes.

But what are Great Circle routes? On a two-dimensional surface map, it may seem like the shortest route between two points is a straight line, but the planet isn't flat like a map! Spherical geometry shows that the great circles are the “straight lines” of spherical geometry. These curves are straight on a spherical plane and thus are the shortest distances from one point to another on a sphere. Earth is almost spherical in shape, and the great circle distance calculation will amount to approximately 95.5% accuracy distance from one point to another on our planet. Ignoring the elliptical nature of the planet, the haversine formula is used to determine this distance given the longitude and latitude of Earth, with great accuracy.

Earth is almost spherical in shape, and the great circle distance calculation will amount to approximately 95.5% accuracy distance from one point to another on our planet.

We are accustomed to seeing the planet on a world map designed as a two-dimensional plane. These maps are known as Mercator Maps. The curvature of the planet is not taken into account and the great circle lines appear as large curves on the Mercator maps, while the Rhumb lines appear as straight lines. These maps are therefore misleading, when they appear to show the Rhumb lines as shorter distances in comparison to the great circles.

The Great Circle route tells us that the shortest distance from Dublin to New York is actually not across the transatlantic ocean, but rather crossing Greenland at varying angles. This is why flights don’t fly across the Atlantic Ocean when flying from Europe to the US/Canada. Flying over Greenland  saves airline companies a large amount of fuel and saves passengers a substantial amount of time. It’s a win-win situation for all.

The Great Circle route tells us that the shortest distance from Dublin to New York is actually not across the transatlantic ocean, but rather crossing Greenland at varying angles. 

In 2022, Russia’s invasion of Ukraine brought a new host of problems for air traffic control systems. In total, flight delays in 2022 added up to approximately 14 million minutes. Russia’s war on Ukraine saw EU aircraft regulators completely close the European airspace to Russian flights and ever since February 2022, EU planes cannot fly over Russia, Belarus, or Ukraine, creating major jet traffic as these planes are diverted to different routes. Europe has been the continent most significantly impacted by this as the majority of Europe’s airspace is blocked due to the Ukraine war.  However, the impact of the Russian invasion on aeronautical traffic remained substantially low in comparison to the Israel-Hamas war and the US-UK airstrikes against Yemen’s Houthi rebels in the Middle East.

The Middle East is one of the locations on the planet that is lucky in its geographical location. Known as an international travel hub, transnational travel is one of the greatest assets of the Middle Eastern economies. Many Middle Eastern airports and flights can connect to any continent in the world with a flying time of approximately eight hours. 

This is why the Middle East is known for being a connecting point for many flights flying from the West to the East, given that the area itself is a midpoint for many air traffic routes that follow the great circle navigation system. An indirect consequence of the Israel-Hamas war and the recent Yemen airstrikes is the changes in flight routes that are flying over the Middle Eastern airspaces. Recently, most international flights have stopped serving Israel and Yemen airports, and diverted flights are taking longer to reach their destinations, deviating from the commonly used Great Circle route. For shorter regional flights, this won't pose a problem for airlines. The Rhumb line route, in these cases, is probably better for the shorter distances travelled by these flights. However, for longer international flights, this causes a significant increase in delays, fuel costs, and emissions. 

Recently, most international flights have stopped serving Israel and Yemen airports, and diverted flights are taking longer to get to their destinations, deviating from the normal Great Circle route.

With the new restrictions and the regulations, some airlines have stopped flying to Israel and Yemen, planes are being entirely rerouted to other routes that often follow the Rhumb line route, or make several stops at other airports to avoid the airports in Israel and Yemen or those neighbouring these nations. Furthermore, the airstrikes in Yemen airspaces have blocked another route for flights, making the Middle East a red-zone for travel. For passengers, the extra time it takes a flight to avoid the Middle East can cost at least €10000. Diverting too many flights around the same route can also cause trouble for air traffic controllers attempting to control the number of flights travelling around the same zones. For every extra hour a flight stays in the air, the carbon dioxide emissions amount to at least 90 kg per person. Not only are the wars affecting the economics of airline companies, but they are also destroying the environment one hour at a time. 

The airline industry has been hit immensely by this deviation from geodesic routes. This increases costs, carbon emissions, and travel time, all of which negatively impact the airline economy. Since the pandemic, many airline routes were removed as a result of dwindling demand. For the past few years, many airlines have gone out of business, and the ongoing wars are affecting the flight business even more.

With the increasing divergence from the Great Circle routes, more aeronautical destinations could be affected, especially leisure flights of lesser demand and importance. Although some airlines have responded by adding new routes, the demand for air travel has decreased overall due to the war. The wars in Europe and the Middle East have already caused an immense amount of civil unrest that prevents leisure holidays and overall international connectivity, diminishing the economies of countries that depend heavily on tourism.

The impact of these wars on the airline industry has been sidelined, and the regulations set by the international governments have posed significant problems for air traffic controllers, airlines, businesses across the globe, and civilians. It is imperative to realise that every second of the war leads to greater consequences not only for humanity but also for the industries of the world and the environment.