A warning has been published over drones which, in a few cases, have unexpectedly suffered “a complete loss of power during flight”.
The problem “resulted in the aircraft falling directly to the ground”, according to the UK’s Civil Aviation Authority.
This occurs even though the battery appears to have charge remaining on the affected model – the DJI Matrice 200.
The CAA has asked pilots to check that flights can be made safely.
While no reports of injuries or damaged property have yet been received by the authority, it said the drones should not be flown above people “at any height until further notice”.
Flying within 50m of people, or vessels, vehicles or structures which the pilot is not also in control of, has also been temporarily prohibited.
DJI said in a statement that it was “thoroughly reviewing” reports of power issues with the model in question.
It advised customers to update the firmware on their aircraft and batteries – steps also recommended by the CAA.
The Matrice 200 drones are slightly larger than the most common consumer drones and weigh in at around five or six kilograms, depending on what equipment – such as a camera – is being carried.
On its website, DJI claims the model is “built to endure” and explains that it has 17-inch propellers.
The Chinese firm continues to develop drones aimed at professional users – such as the new Mavic 2 Enterprise, which has been designed for uses including search and rescue.
Among its features is a 100-decibel loudspeaker that can be used to broadcast pre-recorded messages.
The Mavic 2 and the Matrice 200 are both designed to appeal to commercial clients experimenting with drones for tasks like surveying and site monitoring, said Tom Morrod, an analyst at IHS Markit.
Problems with the Matrice 200 could cause concern in that sector, he pointed out.
“It’s potentially going to slow down a lot of that experimentation, the opportunity to establish new business cases,” he told the BBC.
“Having them not fall out of the sky… is clearly important.”