Aviation consultants To70 have raised questions about training despite revealing a big fall in the number of large passenger aircraft accidents and fatalities in 2019.

There were 257 deaths from 86 accidents, eight of which were fatal, in 2019, To70 said. This included the Ethiopian Airlines Boeing 737 MAX disaster which killed all 157 people on board and grounded the fleet.

This compared to 160 accidents, 13 of which were fatal, resulting in 534 deaths in 2018.

These figures follow a historic low in 2017, when two fatal accidents occurred resulting in the loss of 13 lives.

To70 said the fatal accident rate for large aeroplanes in commercial air transport was 0.18 fatal accidents per million flights. That is an average of one fatal accident every 5.58 million flights. It added there was an estimated 4.2% growth in air traffic for 2019 over 2018.

However, To70 warned that despite the fall in fatalities there remained key issues the industry needed to tackle.

"The issue of derivatives – when a new model of an aircraft type is considered a development of a previous one – is something that is rarely discussed outside the airworthiness world," the company said.

"These accidents also raise important issues about how much information and – most importantly – training is needed on new systems. Questions about how aviation authorities delegate powers to manufacturers are also being asked in wider circles than before."

It added that it was important to retain focus on the fundamentals of aviation safety: "well-designed and well-built aircraft flown by fully informed and well-trained crews."

To70, founded in the Netherlands, uses figures reported by States to the UN’s aviation agency, ICAO, to compile the report.