Magnetic field disrupts £300m island airport
BUILDING a new international airport on one of the world’s most remote islands was always likely to suffer the odd teething problem.
It had taken more than 70 years and nearly £300million to bring the jet age to St Helena, a rocky volcanic outpost in the south Atlantic that was the site of Napoleon’s final exile.
But islanders had not predicted a change in the Earth’s magnetic fields would send the airport back to the drawing board just four years after it welcomed its first public flight in 2017.
Since its completion, the “magnetic declination” of the runway has shifted.
This led to thousands of pounds worth of changes to the £285million airport on the British Overseas Territory.
Magnetic declination is the difference between true north, a constant, and magnetic north, which changes over time.
Shifts in magnetic north are more dramatic the closer you are to the pole and St Helena is particularly vulnerable. As a result, the “20” painted on the runway – for a magnetic heading of 200 degrees – had to be replaced with a “19”. Pilots and air traffic control were told to refer to the runway by a new name. The airport explained: “The cost of the alterations was around £8,000. The project was implemented over a period when no flights were planned.”
Prior to the airport’s opening, the only way to the island was a five-night voyage from Cape Town, more than 1,000 miles away.
The practical difficulties of building the airport on the island, which has a population of 4,000, meant it was decades before it got the go-ahead.
The cost of nearly £300million for one flight a week had left many sceptical. But it is hoped the flights will allow tourism to flourish on the island and offset its reliance on Britain. Last year 2,000 tourists visited but it is estimated this will increase to 30,000 a year by 2042.