Airbus A400M plane crash linked to software fault

The A400M cargo plane crashed near Seville airport on 9 May

Investigators have found evidence a military plane crash in Spain may have been caused by software problems.

The Airbus A400M crashed near Seville, on 9 May, after a failed emergency landing during its first flight.

The four crew members on board were killed in the accident.

A spokesman for the European planemaker told the BBC that its engineers had since discovered anomalies in the aircraft's data logs that could be relevant to the accident.

It has sent out an alert to other air forces that have taken deliveries of the propeller aircraft, saying that they should carry out checks of the Electronic Control Units (ECU) on board.

"For practical purposes, these are computers, and there is one on each engine," the spokesman said.

"What the ECU does is take the pilot's inputs on the controls and then makes the engines perform in the optimum way to achieve what the pilot is asking it to do, taking a whole number of things into account.

"You can conclude that as we've asked for checks to be made on the ECU, that that is the area of interest."

Funerals were held for the plane's test crew in Seville this month

He added that problems had only been found after the company's investigators had checked both the maintenance data gathered by Airbus's flight-operations team and the logs that had been generated during ground tests of flight MSN23.

"The maintenance data is vast streams of data showing everything going on all over the aeroplane, and one of the things we saw seems as if it could be pertinent to the accident," he said.

According to a report by the news agency Reuters, the problem might have been caused by the way the software had been installed rather than an issue with its design.

Grounded flights

The A400M was created to give Europe's Nato partners independent access to heavy aircraft to transport troops and large weaponry.

It was originally budgeted to cost €20bn ($22.3bn; £14.5bn) under a fixed-price contract in 2003.

But European defence ministers subsequently had to provide extra funds to Airbus after cost overruns and delays.

The first plane was eventually delivered to France in August 2013.

But last month's accident means that the countries that have bought the aeroplane - Belgium, Britain, France, Germany, Luxemburg, Spain and Turkey - face the prospect of further delays.

Other A400m planes have been grounded pending the results of the crash investigation

"Until more detail about the cause of the recent A400M crash in Seville is known, the RAF has paused flying of its A400M Atlas aircraft," said a spokeswoman for the UK's Ministry of Defence.

"As an A400M operator, the UK MoD has received an Alert Operator Transmission (AOT) from Airbus Defence and Space, informing us of checks that should be made relating to aircraft engine software, and we can confirm that we will carry these out."

While Airbus is carrying out its own investigations, the official inquiry into the crash is being led by Spanish defence officials, who were unable to provide more detail.

"The competent court has ruled secrecy of judicial inquiries. Therefore [Spain's] MoD won´t comment on any details affecting the course of investigation," said Capt Miguel Gonzalez Molina.