Spanair accident at Madrid

[SPA83]

http://www.sepla.es/website/seplacms/index.php?option=com_content&task=view&id=532&Itemid=1
google translation…

Repairing the damage from last MD-82 Boeing violated rules
Friday, 03 October 2008
El Mundo


Marisa RECUERO / Madrid. Spanair failed to diagnose the fault of the plane that crashed in the Barajas August 20, in which 154 people died. The maintenance technician isolated the problem identified by disconnecting a fuse, but did not make a detailed assessment of the rest of systems related to the mechanism that failed, as recommended by Boeing.

The manual provided by the manufacturer to the airline to give instructions on how to use the list of teams with the minimum permitted that can fly a plane-that is, MEL, as he is known in aviation jargon, contained in paragraph 34 that in the event that the temperature sensor is inoperable, the maintenance technician should check the effects this could have lead to systems related to this mechanism. MEL agreed in the Procedures Manual for Boeing, which has had access to this newspaper.

By the same token, there is another manual, which also had access to the world, which recommends the same. In this case, this is the book that Boeing provides to the airlines so that they know what teams with minimal can fly an aircraft, namely the so-called Master MMEL or MEL. In it, the manufacturer warns that other systems should be checked when the Ram Air Temperature (RAT) was inoperative.

The problem is that the maintenance technician who consulted Spanair did not include any procedure to follow to fix an overheating in the probe temperature, as confirmed by sources close to this newspaper's own technicians.

The person who isolated the fault which complied with orders to the operating airline. First, we consulted the list of teams with the minimum that can fly the plane and found that the aircraft could make the flight with the temperature sensor inoperable. Second, because the maintenance manual does not include what to do after a failure of the probe, the technician goes to the Wiring Diagram, this is a book about the system of wiring the aircraft, which tells you that you can turn off the fuse.

The crux is that the heater probe of the RAT failed five times in less than 48 hours, according to the summary of the case, but no one noticed consult the book that explains the procedures to follow to cope with failures associated with the RAT. A day before the crash, the probe will overheat four times. The technician reset the mechanism-what-lit and extinguished and dispatched the aircraft. The day of the incident, he again produced the same bug. The commander Antonio Garcia Luna decided to return to the park and the technician removed the fuse Z29 does not go beyond that.

Before giving solution to this latest failure, the technician was known that the heater probe was activated only when land had to operate in the air, at least so declared and recorded in the summary, the person responsible for maintaining the aircraft to the judge Javier Perez, who directs the event of an accident.

Every plane has a mechanism which is responsible for communicating with the aircraft when it is in the soil or is in the air to perform other functions. It is the so called air-land the plane. This mechanism is located, through a sensor in the front leg of the landing gear, is the functioning of the RAT, in addition to 25 other systems.

One is the sound system of alerts that warns pilots of the configuration ready for take-off is not correct, namely that the flaps and slats-small rear wings and front wing, respectively, are not in the proper position for takeoff.

The first draft issued by the commission investigating the crash of the MD-82 Spanair confirmed that the flaps were not widespread and that the sound system alerts did not work.

The list of failures of deferred Sunbreeze, ie, with which the aircraft can fly for a limited period of time, which is the mechanism that inhibits the warming of the earth in temperature sensor would have failed so repeatedly. In fact, at the time of the tragic off, there was a change in the signal so as to land air. However, an hour earlier, the commander detected otherwise.

The train nose of the plane, which is the place where the sensor surface-to-air mode, was manipulated by the technicians a week before the accident, in particular the Aug. 13. The reason was the settlement of a deferred warned that three days earlier (on August 10). The technicians changed the water and dirt deflectors located in the nose.

Industry sources warned, even that the strobe lights, that is, white lights that identify the plane with flashes when it is in the air, operated on land.

With this background scenario, it is clear that the procedure followed by Spanair is insufficient. But most importantly, the Directorate General of Civil Aviation is the one that authorizes the manuals of the companies