5 July 2012 Last updated at 10:02 ET

Mid-Atlantic air crash 'due to pilot and technical failure'

Author M R Hall said the pilots "did not know if they were climbing or descending"

Technical failure and human error led to the loss of an Air France flight over the Atlantic in June 2009 and the deaths of 228 people, including County Down doctor Eithne Walls.

The final report into the crash by France's aviation authority, the BEA, says the crew did not react correctly after the Airbus A330 had technical failures.

Dr Walls, 28, died along with her friends Aisling Butler, from Roscrea, County Tipperary, and Jane Deasy from Dublin.

Dr Walls, from Ballygowan, County Down, who worked in the Dublin Eye and Ear Hospital, was also a talented Irish dancer. She had spent a year with Riverdance on Broadway, New York, before going on to Trinity College, Dublin.

Eithne Walls was a talented doctor and dancer

The three friends were returning from holiday.

The jet disappeared from radars while en route to Paris from Rio de Janeiro.

It took nearly two years for the flight recorders to be found.

The report makes 25 new safety recommendations on top of the 25 called for in a preliminary report released last year by the BEA.

That report also said the pilots did not follow the proper procedures after the aircraft's speed sensors failed when the plane encountered turbulence two hours after take-off.

Speaking at the release of the final report, BEA chief investigator Alain Bouillard said the two pilots at the controls never understood that the plane was stalling and "were in a situation of near total loss of control" as the plane descended at 11,000ft (3,352m) per minute.

The captain was taking a rest break and the co-pilots were in control when the first problems occurred. The captain returned to the flight deck but was unable to reverse the catastrophic course of events.

One of the mistakes of the crew was to point the nose of the aircraft upwards after it stalled, instead of down, the report said.

Manslaughter claims

Investigators have found fault with both Airbus and Air France, sparking a row between the two firms over their accountability for the crash.

Both companies are under investigation by French magistrates for alleged manslaughter.

A separate judicial report will be released next week. This is also expected to echo Thursday's report by the BEA, the French news agency AFP says.

Since the crash, Air France has replaced the speed sensors on its fleet of Airbus jets - made by the French firm Thales - with a newer model.

The wreckage of the plane was discovered after a long search of 10,000 sq km (3,860 sq miles) of sea floor.

After 23 months of searching, robot submarines finally found the flight "black box" recorders last year.

The final minutes of Flight AF447

1. 0135 GMT: The crew informs the controller of the flight's location

2. 0159-0206 GMT: The co-pilot warns of turbulence ahead before the captain leaves the cockpit for a rest break

3. 0208 GMT: The plane turns left, diverting from the planned route. Turbulence increases

4. 0210 GMT: The auto-pilot and auto-thrust mechanisms disengage. The plane rolls to the right. The co-pilot attempts to raise the nose. The stall warning sounds twice and the plane's speed drops. The co-pilot calls the captain

5. 0210 GMT: The stall warning sounds again. The plane climbs to 38,000ft

6. 0211-0213 GMT: The captain re-enters the cockpit. The plane is flying at 35,000 ft but is descending 10,000 ft per minute. The co-pilot says "I don't have any more indications", pulls the nose down and the stall warning sounds again

After location 6. 02:14 GMT: Recordings stop

Source: BEA. Note: Last known position = last known position before the plane's "black boxes" were retrieved