What are the world’s most challenging routes and airport approaches?

Over time, developments to aircraft systems have made remote locations much more accessible. However, many locations across the world are still difficult for aircraft to approach for a number of reasons, including high terrain, hot climates or expansive stretches of ocean.

We take a look at some of the most challenging routes and airport approaches:

1. Hot and high: Both hot temperatures and high altitude affect the amount of lift available. Put these both together and it creates a tricky approach for aircraft. Take, for example, Ethiopian Airline’s main hub, Addis Ababa Airport. At 7,625ft, the altitude of this airport, plus its warm climate, can heavily influence long-term fleet decisions and the day-to-day flight planning and operations for the flag carrier.
    
2. Difficult approaches (Part 1 – Terrain): When it comes to difficult approaches, Paro Airport in the Kingdom of Bhutan is one of the most notable. A short runway on the floor of a deep valley and surrounded by 18,000ft mountains, its position lends itself to special training for pilots and day-time operations only add to the challenges of flying to this mountain kingdom.
    
3. Difficult approaches (Part 2 – Late manoeuvre on final approach): The best example of this was the legendary approach into the old Hong Kong Airport at Kai Tak which required a steep turn onto short finals only two miles from touchdown, all above one of the most densely populated parts of Hong Kong. As the name suggests, Checkerboard Hill features the distinctive black and white pattern to act as a visual reference marker on the final approach to the runway. Although somewhat peeling and faded it remains today as a reminder of the difficult aircraft approach into a unique airport.
    
4. Difficult approaches (Part 3 – Wind shear): A microclimate change of wind can be incredibly dangerous in the final moments before landing. Wind shear affects a number of airports – including the new Hong Kong International Airport on the island of Chep Lap Kok, Seychelles International Airport and the Cristiano Ronaldo International Airport in Portugal – due to their landing area’s close proximity to mountainous terrain. Even the easterly approach into Gatwick Airport used to be subject to occasional wind shear due to the now demolished large hangers on the southside of the runway.  
    
5. The tide is high: There are sometimes limited options when choosing where to build an airport. Spare a thought for the islanders of Barra in the Outer Hebrides, Scotland, whose timetable is affected by the changing tides. Considered to be one of a kind, its runway is situated on a tidal beach. Although this means that on a clear day the views are spectacular, the proximity to the Atlantic Ocean brings changeable weather conditions, and with it, potential flight disruption and further challenges.
    
6. Long overwater routes: There are several routes that fly over large expanses of water where the nearest safe landing spot is hundreds of miles away. Two notable challenging routes are Johannesburg, South Africa to Perth, Australia, and Santiago, Brazil to Auckland, New Zealand, both of which fly over the southerly oceans and operate under Extended-range Twin-engine Operational Performance Standards (ETOPS) rules, requiring special clearance for the airline and the pilots to use the route.

Advancements in technology are enabling operators to become less constrained by challenging routes and airport approaches. To find out more about Cordillera, which removes historic limitations over high mountain areas, and gives operators more flexibility and freedom to fly routes that may have previously been avoided, such as over expansive water and in hot and high environments, read our dedicated page here.