Planes at ‘risk of crashing’ from ingesting dust and sand while circling before landing

Researchers found aircraft ingest more dust while they are performing holding patterns before landing
Researchers found aircraft ingest more dust while they are performing holding patterns before landing - Teresa Colucci/iStockphoto

Planes flying to the Canary Islands could be at higher risk of crashing because they suck up more dust, a study has suggested.

Experts are becoming increasingly aware of the dangers posed by the accumulation of dust on aeroplane engines, which disrupts airflow and causes overheating.

Researchers from the University of Reading compared the amount of dust and sand swallowed by jet engines flying into 10 of the world’s busiest airports over a 17-year period.

They found that around 10 kilos (22lbs) of dust are being ingested by engines per 1,000 flights, with the majority occurring while circling before landing.

All of the airports were located in desert regions or subject to seasonal dust storms, such as near the Sahara desert, the Middle East or Northern India.

Summer flights into Delhi, India, ingested an average of 6.6g per arrival in the run-up to monsoon seaso
Summer flights into Delhi, India, ingested an average of 6.6g per arrival in the run-up to monsoon season - Kriangkrai Thitimakorn/Moment RF

Summer flights into Delhi, India, topped the list, with planes ingesting an average of 6.6 grams per arrival in the run-up to monsoon season, and 4.4g upon departure.

Dubai, United Arab Emirates, and Niamey, Niger, followed with 4.3g and 4.7g per arrival respectively, while flights into Beijing, China, sucked in 2.9g of dust and sand on average.

Other airports were based in the Canary Islands, Marrakesh in Morocco, Phoenix in the US, Hong Kong, Bangkok in Thailand, and Sydney in Australia.

Dr Claire Ryder, lead author from Reading University, said: “Dust and sand are dangerous to aircraft because dust melts to form glassy deposits on blades or hard mineral crusts inside engines.

“These crusts disrupt airflow and cause overheating, resulting in accelerated engine wear,” she said. “Although the amount of dust ingested per flight is not huge, the amounts quickly add up.

“A plane consuming five grams of dust per arrival and departure will eat 10 kilos of dust over 1,000 flights.

“Planes will consume more dust when they are at lower altitudes waiting to land at, though this depends on the local weather conditions which affect the height of a dust plume in the atmosphere.”

She said that climate change may lead to a “dustier world” as temperatures rise and deserts expand.

Performing holding patterns

The researchers found that aircrafts ingest more dust while they are performing holding patterns – the formation they assume while pilots are waiting for permission to land.

The findings suggest the greatest amount of dust ingested is when an aeroplane circles at around 1km while waiting to land.

Holding patterns of 10 to 15 minutes at a one-kilometre altitude can lead to more dust ingestion than during the take-off, climb and taxi phases of a flight.

It said by changing the holding pattern altitude away from the dusty layers, dust ingestion could be cut by 41 per cent.

The researchers also suggest dust exposure could be reduced by changing flight schedules to avoid peak dust times.

They say shifting flights at Delhi and Dubai to night-time could reduce engine dust ingestion by more than 30 per cent.

The study was published in the journal Natural Hazards and Earth System Sciences.