Meet the new beast of the skies whose gentler growl has bosses at Heathrow purring.

Qatar Airways' new Airbus A350 XWB was given a water cannon salute as it landed at the airport for the first time on Saturday.

Heathrow chiefs today heralded the arrival of the latest model to grace its runways as a major landmark in the quest for quieter, less polluting planes.

They said the new aircraft operated at up to 21 decibels below the regulatory standards for a carrier of its kind, while belching out fewer carbon emissions than its predecessors.

Matt Gorman, Heathrow's director of sustainability, said: "Heathrow is proud to count on airline partners like Qatar Airways to use the quietest and most modern aircraft on our routes.

Heathrow CEO John Holland Kaye with Qatar Airways' vice president for Europe north, south and west Jonathan Harding, and Qatar ambassador Yousef Ali Al-Khater

"We are committed to phasing-out the noisiest and oldest aircraft in the short-term, and ensuring that new aircraft like A350 XWB are taken up by all our airline partners in the long-term, to the benefit of local residents."

Heathrow has long claimed technological advances will pave the way for progressively quieter planes, allowing a third runway to be built while reducing the number of people affected by aircraft noise.

But critics of the airport's expansion plans, including MP Zac Goldsmith, continue to question the airport's evidence for such claims. They say there is no proof improvements will continue at the rate they have done in the past.

Quieter planes are just one way the airport says it can reduce the impact of aircraft noise on its neighbours, with steeper approach paths among the other planned changes.

Heathrow's blueprint for noise reduction outlines the airport's ten-point plan to cut noise by this summer. One of those measures is an early phase out of Chapter 3 planes, the oldest and noisiest aircraft in our skies, and exploring a stronger round of incentives like increases in landing charges for older aircraft.