A Spanair jet which crashed at Madrid airport last month, killing 154 people, had faulty wing flaps and a warning system that failed to sound, an initial report into the crash has found.

An automated voice warned "stall, stall, stall" in the cockpit of flight JK5022 to Las Palmas moments before it climbed 12 metres into the air and then flopped back down onto its tail and careered off the runway.

The McDonnell Douglas MD-82, loaded with 10,130 litres of fuel, shot across one kilometre of scrub before falling into a small ravine and bursting into flames, said the report, published on the Transport Ministry's website.

Only 18 passengers survived the accident, Spain's worst aviation disaster since 1983.

Data from the plane's black box flight recorder showed the flaps were flat and not pointed down to give the plane lift. The report, carried out by the Civil Aviation Accident Investigation Commission, added that slats at the front of the wing were also not deployed.

Despite this, the take-off warning system failed to ring, which might have given pilots time to abort the takeoff. It added that both engines appeared to be working normally.

Scandanavia's SAS, which owns Spanair, said this week the accident would slash €51.7 million from its results due to lower bookings.

The 12-page report said investigators would conduct exhaustive tests on wreckage recovered from the crash while they would also continue analysing flight data.

The MD-82 jet arrived in Madrid's Barajas airport from Barcelona at 10.13 a.m. and was preparing to fly on to Las Palmas in the Canary Islands when the pilots informed the flight tower of a problem and taxied back to hangar.

The plane returned to the terminal where technicians found overheating in a gauge and removed a fuse from the circuit. After temperature returned to normal the plane taxied back to the runway, before the attempted take off at 2.23 p.m.