James W. Hudspeth, American chief pilot with Austrian MAP, owners of the MD-83 OE-LMM at the time of the similar incident in Lanzarote last year, came out an spoke in an article for a Spanish newspaper.
On june 4th 2007, the day before the INCIDENT, the pilot of OE-LMM (an MD-83, similar to Spanair's MD-82) called out maintenance on a "faulty RAT sensor signaling higher temperature than should". The heater, of course, was erroneously on while on the ground. Technician's action: they pushed a popped circuit breaker (LEFT GROUND CONTROL RELAY).
On the MD-83, most systems that depend on front wheel ground/air logic, are duplicated on circuits from the "right wheel" and the "left wheel". But the RAT probe heater, strobe lights, take off configuration warning system (TOWS), and some ventilation/air conditioning systems are serviced exclusively from the left circuit.
The flight in Lanzarote (ACE), with destination Barcelona (BCN), making a service for Air Comet with 140 passengers on board and 6 crew, lined-up without flaps. "I saw the black boxes and there were no flaps or slats: the crew never deployed them, but the Take Off Warning System alarm didn't sound either", Hudspeth explained.
The same thing had happened 20 years before in Detroit on a similar plane operated by american Northwest. The CIAIAC report on the Spanair case mentions this prior accident, but fails to mention the Lanzarote case although they've had all the data on it being analyzed for well over a year.
The MD-83 is more "powerful" than the MD-82. That saved the plane. "Although the MD-83 was at max capacity for that runaway (ACE), around 65.000kg, that is not the maximum capacity it can carry", said Hudspeth. It was at 89% capacity, while Spanair's was operating at 96%. "Our crew was able to keep the airplane airborne, as they had a nice front-wind and more powerful engines (with the runaway being short, they also quickly retracted the landing gears). That allowed them to control the aircraft."
(Also, ACE runaway is at sea level and temperature was probably around 25º, while MAD is elevated, temperature was 30º, and w/ 6-8 knots of tail wind)
But barely. The aircraft almost touched the runaways barriers and buildings in front of it. It made (wing stall induced) uncommanded rolls of up to 55º (
), much steeper than Madrid's case (where the steepest was 32º). Tragedy was close.
(The pilots declared an emergency and turned around. They realized the flaps' handle was up, and they landed. Witnesses speak of the airplane clearing obstacles by "barely a couple of meters" and showing a very erratic flight behavior. Some people in the flight path threw themselves on the ground thinking the airplane was going to crash on them. The pilots are said to have exited the airplane in state of shock, even crying.)
Hudspeth, was chief pilot for Mapjet at the time (who rented out airplanes to other airliners) and he flew personally to Lanzarote to figure out what happened. "We found out that in the cockpit one circuit breaker was pulled, the one that would signal TOWS and RAT if they are on ground or air mode. Nobody tells you about that c/b, but it is very important and pilots should check it every time they board an MD."
In Detroit's case, it was never conclusively found out why the TOWS alarm didn't sound. The investigation could only conclude a generic "electrical failure". In Mapjet's, because the airplane was intact, it was found out what the cause was and why it had happened. "We took the airplane to be thoroughly checked in Stockholm, and they couldn't find anything wrong with it other than the circuit breaker was pulled out".
Hudspeth investigated why the c/b was out and found that "It was a very common procedure during maintenance. Mechanics, during daily checks, would pull it to check the strobe lights while on the ground. We couldn't find proof that it was left out by mistake, but it is within human nature to sometimes forget to put things back".
The c/b panel on the MD-83 is behind the pilot's back. Crew should check them over their shoulders when they enter the cockpit to verify they are all in correctly. In Lanzarote, "The white 'collar' around the cb in the panel that signals if the circuit breaker is pushed in or pulled out was dirty-black from so much usage, which made it hard to notice if it was out".
In Lanzarote's case, company investigation concluded that the austrian MAP's crew, veteran argentinean pilot Ricardo Simaro (ex president of a pilot's association) and copilot, venezuelan Rodolfo Ovelar, did not deployed the flaps/slats, didn't check the TOWS alarm system and didn't notice the pulled c/b that a technician had left improperly out that same day before the prior flight".
The most shocking part of the investigation is that the company found out that at least another 6 times in the previous 3 months planes from their fleet had flown in that state (i.e. TOWS disabled, RAT heater connected on the ground, therefore, likely wrong outside air temperature readings).
Figuring out around 850 similar MD's flying around the world, makes it very likely that many are routinely taking off with the c/b not correctly set. He says the design should be improved, as well as maintenance instructions and pilot awareness.
During his investigation, he found out that during maintenance in Dublin, Warsaw or Madrid, pulling this c/b was something common. "A pilot told me that, in Dublin, the RAT heater was noticed turned on while on the ground, a technician came on board, immediately pushed the c/b like if he already knew what the problem was and it got fixed".
In Madrid, though, the technicians for Spanair didn't make the connection between the probe heater miss-behavior and faulty ground/air logic. The technician in Madrid didn't check the state of the Left Ground Control Relays c/b, situated in position K-33 of the c/b panel, he only concentrated on RAT probe itself, checking Z-29 in the lower right of the panel.
(Most likely scenario in Spanair's case is that this c/b was in the right pushed-in position and it was the R2-5 relay that malfunctioned, producing similar but even less conspicuous results).
Hudspeth informed of all of this January 24th to the CIAIAC, where, incidentally, he "met with the (female) investigator, another man, and a SPANAIR CAPTAIN that was acting as advisor in the investigation. My declaration was taped for over 2 hours and I told them all this, but they haven't done anything".
CIAIAC has declined to make comments about this, as they (oh gosh, how much I hate secrecy for the sake of secrecy) "Do not comment on ongoing investigations until they are final".
He also was puzzled as how the investigators kept questioning him on how it was possible that the pilots forgot to deploy the flaps/slats, and he found odd that they didn't concentrate much on why the TOWS didn't sound, as "if they already knew about the problem".
Also, it seems, the RAT probe heater in Madrid's case was also "acting-up" the day before. But it seems that it only reached 90º. It wasn't until the hot mid-day Madrid that the probe went over 99º (105º), and it is only then when an alarm goes off in the cockpit to indicate the condition on limited automatic gas intake for the engine (autothrust warning?). The taxing of the MD-82 form Madrid's T2 to the runaway on T4 was longer and in hotter weather than the conditions on the MD-82's previous flight of the day, early in the morning in colder Barcelona.
Although it wasn't conclusive, it took Detroit's crew two attempts to engage automatic gasses intake (autothrust?), pointing to a potential similar problem.