This trial which will take place between May and October follows on from the initial slightly steeper approach trial it held between September 2015 and March 2016 which tested a 3.2 degree approach angle. The international standard approach for most airports in the world is set at 3 degrees, except for obstacle clearance e.g. buildings, terrain etc.
“Following the conclusion of the initial trial, we sought permission to introduce the procedure on a permanent basis,” the airport said on its website. “The UK CAA was supportive of this but has requested that further data should be collected during warm months to consider the effect warmer temperatures have on approach angles flown, so a second trial is now being conducted. If this shows no adverse impacts, then we will look to start the process of making the approaches permanent.”
This latest trial will gather data to better understand how a slightly steeper approach angle would impact Heathrow’s operation.
“We believe that a steeper angle is possible and that this, in conjunction with a number of other Heathrow initiatives, will lead to quieter approaches to the airport. As we have done over the last few decades, we will continue to explore initiatives like this to further reduce Heathrow’s overall noise footprint to improve the impacts on the ground,” it said.
“Our long term aim is to introduce approaches of up to 3.5 degree in the future, and we plan to incorporate steeper angles of descent into our proposals for redesigning the Heathrow airspace as part of the UK government’s Future Airspace Strategy.”