Scientists researching the effect of dust on aircraft have discovered that planes flying in and out of Delhi, India, suck in more dust than at any other airport. The study led by Dr Claire Ryder and the University of Reading, UK, followed previous work looking at the impact of ash on aircraft, but this time focused on mineral dust.
The team used Copernicus Atmosphere Monitoring Service (CAMS) model reanalysis to calculate the climatological and seasonal “dust dose” at 10 airports for the years 2003 to 2019. The airports looked at were: Bangkok in Thailand; Beijing in China; the Canary Islands; Delhi, India; Dubai in the United Arab Emirates; Hong Kong; Marrakesh in Morocco; Niamey in Niger; Phoenix, USA; and Sydney in Australia.
Delhi planes eat more dust
Delhi planes are dusty, the results suggest. Arriving at Delhi in the summer, planes ingest more dust than any other airport, the study found, on average 6.6 grams of dust on descent and 4.4 grams on departure. What’s more, flying planes in holding patterns at around 1,000 metres’ altitude where dust particles sit in the atmosphere makes them more vulnerable to ingesting more dust, the team said.
While a few grams of dust per flight might not seem much, there are safety and maintenance implications and potential for increased wear and tear. The study’s abstract notes that “mineral dust aerosol constitutes a threat to aircraft engines from deterioration of internal components.”
And as Ryder has pointed out speaking to Interesting Engineering, “A plane consuming five grams of dust per arrival and departure will eat 10kg of dust over 1,000 flights. Planes will consume more dust when they are at lower altitudes waiting to land, though this depends on the local weather conditions which affect the height of a dust plume in the atmosphere,” Ryder said.
Night flights could cut dust dose
Controlling dust around airports is a complex task, due to the variety of conditions that lead to the phenomenon, including the amount of available sediment on the bare ground, wind speed, and drought. But there are potential solutions, such as “moving arrivals and departures to after sunset” and “altering the altitude of the holding pattern away from that of the local dust peak altitude”. These could cut the dust dose by up to 44 % or 41 % respectively.
Avoiding certain altitudes for holding patterns and landing more planes at night could be the answer to reducing dust ingestion then, but the latter is a solution that might cause consternation at the least among local populations around airports, who are already dealing with the effects of noise pollution.
