Air accident investigators have reported on an unusual incident which caused a small passenger aircraft to make an emergency landing at Hawarden Airport last October.
A burning smell inside the Jetstream 4100, G-MAJC led to Mayday being declared and oxygen masks being donned.
It later emerged the smell was the result of smoke and dust carried in the atmosphere from North Africa and Iberia.
Earlier the flight crew had reported for duty at 6am at Leeds Bradford Airport on October 16, 2017, according to the Air Accidents Investigation Branch report.
The original schedule was changed due to another company aircraft being unavailable. It was assigned to travel to Bristol International Airport and then fly on to Hawarden with passengers.
As the aircraft was descending to Hawarden the flight crew started to notice a burning smell.
It appeared to them the smell was coming from the air vents on the flight deck. They donned their oxygen masks and attempted to verify communication between themselves, but found it difficult because of high noise levels coming through the cockpit speakers.
Safety actions were agreed following a meeting held by the UK Civil Aviation Authority together with representatives from the NATs air traffic control company and the Met Office.
The Met Office advised accurate forecasting of such phenomena is problematic because it is hard to forecast the extent and height at which the smoke is likely to be present due to the difficulty in accurately locating the fires.
In future, Met Office systems will issue smoke-related details in its bulletins if informed by NATs there is significant smoke in the atmosphere affecting aircraft operations.
Participants agreed to improve the dissemination of information about such unusual events in the future.
The operator also conducted its own internal investigation and identified safety recommendations and actions. This included enhanced training on use of oxygen masks, drawing up a list of approved headset types compatible with the aircraft communication systems and updating the passenger emergency briefing to include a warning about the danger of rotating propellers.
Such a scenario involving unusual atmospheric conditions will be incorporated into the company training programme.