Spanair accident at Madrid

[west lakes]

Though a few days old I found this

Spaniards mourn victims of plane crash - International Herald Tribune

well down the page

"The control tower saw there was something wrong and immediately sent out the alert."

Though not free to talk, owing to the investigation, there were no doubt reliable witnesses in the VCR

[azalea]

Originally Posted by JM340

After seeing this photo above, I believe at the theory of a deployed reverse thrust on the starboard engine, too.

It seems that the aircraft get a severe drift to the right. But the turn was going exclusively along the vertical axis as no wing marks can be detected on the ground.
It can be assumed that the wings where leveled (I believe this is quit typical for tail powered aircrafts in a event of asymmetric thrust) in the moment of the impact.

After touching the ground the right drift was still highly intense and the crew had no control until the front gear was lowered.

In the Moment the front gear has touched the soil (thats seems to be the trail from the left to the right - crossing the trails of the maingears) the crew became back control and could stop the right drift. More than that they could turn the aircraft in an opposite direction but unfortunately there was not quit enough space before the dip.

That’s my 2pence. I know, its speculation again. For the truth we have to wait to the end of the investigation

[threemiles]

How can the nose gear go straight when the main gear curves around? Either something was detached and continued its way or something hit the ground at the very end of the airplane when the front/main gear had crossed the service road on a straight and parallel track.

Overall site views:

[jonesyboy]

threemiles

How can the nose gear go straight when the main gear curves around?

Try a simple experiment with your hand with the index finger as the nosewheel - it is possible

[Frangible]

Lots of others apart from LHR would not make a 300m standard, especially in the US. All the same, LHR is antique and there are all sorts of things you wouldn’t do now that might have been done then. IIRC the top of the LHR Renaissance hotel very nearly got dinged once or twice.

It is not so much the frequency with which bad crashes happen in the overrun areas, although there seem to be a helluva lot of them, but the ease, in places other than LHR and other antique sites, with which you can avoid most of them (e.g. ditches, berms, sunken roads etc.), whether or not this crash was a case in point.

[justme69]

The video worked for me (inside Spain).

From the TV press conference:

-4 experts from the US aviation authorities plus other representatives from the plane as well as the engines manufacturer were allowed on the site thursday morning, joining forces with the national aviation accident comission of Spain (total of 9 experts).

-The site had already been investigated by the spanish comissioners, as early as 1.5h after the crash, who found the second black box (the first was handed over by police that took part on early rescue efforts).

-Significant avionics parts of importance for the investigation have been found. Damaged, but in good enough state to provide evidences.

-Auxiliary power unit also retreived.

-No skid or crash marks found INSIDE the airstrip. Please, note, that this are just "facts stated". It doesn't mean that the airplane didn't touch the strip at all (or that it did). It only means that most likely it never touched the strip while trying to brake or "crashing down hard", and, likely, but not necessarily, ever at all since it left the ground. So, again, no marks, skid or otherwise, of the plane on the actual runaway. He does state that "the first point of impact (implying in absolute terms) of the plane with the ground was the back of the tail.

-It is mentioned that some (of the 4) channels of the AUDIO (not data) recorder that are in better shape than others. The data recorder information has been apparently succesfully reported, but it has been sent to the manufacturer and it's being verified.

-It was stated that the ground level radar recorded the take-off attempt, so possibly some speed and trayectory information can be extracted from that.

-He is confident enough technical data (both black boxes, significant parts in good enough state to be studied, video, radar and other visual information, survivors and witnesses reports, all pertinent weather information, ground control recordings, etc, etc).

-The pilot's conversation recording has not yet been transcribed. They are not currently able to clearly hear everything in there, and further analisys and proccessing is necessary and currently underway in laboratories.

-When directly asked about the reversers, he just acknowledge that both reversers as well as both engines have been recovered in reasonably good condition. But he refused to comment on their state, saying that whatever state they were apparent may or may not be enough to reach any conclusions at this point.

-He reiterated that no marks, parts or debris has been found on the actual landing strip itself. The first one is in the flat terrain inmediately to the side of it.

[blackboard]

1st BOARD REPORT

Having just watched the whole press conference hosted by the Board this evening, in my opinion the main items are already posted by Justme69:

-By their regulations, they are required to present a preliminary, factual report (no conclusions or probable causes, just the facts stated), in aprox. 1 month. Actual investigation thought to last several months.

-It's confirmed that the voice recordings and the fly data have been extracted in the UK facility it was sent. They are now being enhanced (voice clarity, etc), recovered & verified.

-He hasn't witness the airport video footage of the accident, but it is part of the investigation and others have seen it.

-Based on marks on the ground, it seems that the airplane first hit the ground outside of the landing strip, on the service route just adjacent to it, touching the ground first with the tail, tail cone coming off.

-Plane kept tumbling ahead for 1200m, bouncing 3 times (matching unlevel terrain marks).

The data I will now add is a very summarized account of the 73 mins press conference.

The conference was chaired by the President of the Board (Pablo Palomar) and presented by the Secretary (Francisco Javier Soto, investigation director for JK 5022) and structured in six sections:

1-GENERAL CONSIDERATIONS
2-FIRST ACTIONS
3-BOARD STRUCTURING
4-BOARD ACTIONS TO DATE
5-PLANNED ACTIONS
6-QUESTIONS

1-GENERAL CONSIDERATIONS

The usual ones about only preliminary factual data available now and no speculation.
Fully independent though government board.
Request for help from media and all citizens with relevant data

2-1st ACTIONS

The board was called upon by the airport upon activation of the Emergency PLan within minutes of the event.
Two hours later, six members of the Board were on site, split between ATC/airport and crash site.

Access to crash site was somehow limited due to firefighting and rescue going on.

FDR was recovered by Board investigator. CVR was delivered to investigator by Judiciary Police [looks like full collaboration for once! [see Concorde, hampering of investigation by french judge as reported by UK AAIB]

3-BOARD STRUCTURING

US NTSB was notified immediately. UK AAIB and other offered immediate support.
NTSB sent 9 people to the field next day (4 NTSB +5 Boeing&Pratt&Whitney)

Three field teams:
-Airworthiness, systems and structures
-Powerplant
-Survivability

Four additional teams:
- ATC+Airport
-OPS
-Maintenance
-Voice/Data recorders

4-BOARD ACTIONS TO DATE

-Collect, recover, classify and preserve all evidences
-Collaboration with judiciary authorities
-Aerial photogrametry perfomed by Spanish AF
-Engines, T/R's and APU recovered in reasonable state of integrity
-Some avionics boxes with NVM's (non-volatile memories) recovered
-Found significant deterioration of some evidences due to rescue and firefighting. Sr Soto said this is reasonable and unavoidable, as preservation of life is prioritized over preservation of evidence.
-Found no marks or remains on runway. Only to the RH side of the runway [see posted photo of gnd tracks]. 1200m since start of marks until final crash site, marks stopping three times matching unevenness in terrain.
-First ground contact outside runway was with tail area, then main gear. Tailcone apparently detached upon first contact. [upon further interrogation, the Board referred to the tailcone as the whole area of the fuselage aft of the rear pressure bulkhead, which is likely incorrect]
-Witnesses interviews and data recovered:
Mechanic
Airline
ATC/Airport
Survivors
Other
-Damaged recorders sent Friday 23rd to UK AAIB. Integrity of data reasonable. Of the four CVR channels, some better than others, downloaded Friday. FDR downloaded over weekend, data sent to Boeing, NTSB and Board
-Additional actions connected to:

ATC
Videos
Pictures
Gnd surveillance Radar
Weather
Judiciary Police

5-PLANNED ACTIONS

-Gathering of evidences
-Detailed inspection
-Prelim factual report in one month, only for confirmed evidences
-Analysis
-Final report incl conclusions as to probable causes and recomendations

[no mention was made of other interim reports]


6-QUESTIONS

All of the (expectedly numerous) Q's for conclusions remained (expectedly) unanswered.

The information from those that were answered is basically:

-No evidence yet supporting actual aircraft max flight altitude
-Airport video is from operational support camera, only qualitatively useful
-The judge will be informed of board's progress
-GND surveillance radar expected to be useful in determining precise trajectory
-T/R's recovered and preserved
-Terrain unevenness significantly increased aircraft damage
-Documents being recovered from operator as well as from the crash site

Sorry for the long account. I hope it helps

[azalea]

Originally Posted by threemiles

How can the nose gear go straight when the main gear curves around?

Well, I believe it is quit easy! Just compare Asymmetric thrust with a crosswind situation.

For instance take a look at this
http://http://www.youtube.com/watch?v=y_7KMHWDgpw
and imagine the captain would not turn back the aircraft-nose hardly before touch-down. By chance you would get a similar “footprint” of the gears, wouldn`t you?

[Old_Fokker]

CAIAIC Press Conference Transcript

Thanks Blackboard!

After watching the entire video and translating relevant info to post it here, I see you have just done that!

One tiny issue though which I understood differently: "it seems that the airplane first hit the ground outside of the landing strip, on the service route just adjacent to it" is what you wrote. I don't think the term 'service route' is accurate. I believe that what was stated is 'the strip of ground' adjacent to runway 36L. If that is commonly designated as 'service route' then I apologize but I believe it can be confused with the road which runs parallel to the runway.

One thing I'd add is the question regarding the tail-cone. The CAIAIC confirmed that it is the entire section after the pressurized bulkhead which was separated.

Otherwise my transcript is virtually identical to yours!

[xkoote]

Geez, this thread moves fast. Another few comments from the picture.

First of all it is completely possible for the nose to travel straight but not the mains. In the automotive world it is called drifting. You purposely release grip on the rear tires by spinning them (in this scenario by rolling on grass and loose dirt). This frees up the tail section of the vehicle to react to side forces. This is achieved by yanking motion on the steering wheel. In this scenario it is created by a lot of factors. Such as engine failure, reverser deployed, "hitting the right wing tip on the ground" (although not seen clearly on the photo it was mentioned to happen) and inertia forces creat by whatever could have happpened.

3 seperate items from that foto corroborate the nose right side slip.

1. If the tail struck first in a nose right slip (meaning the plane moves in a direction more in line with the runway track while the nose points off to the right) it can be explained as a reason why the tail cone is resting further along the runway i.s.o. in line with the main gear tracks (more or less)

2. Try imagining the mains and nose gear to hit the ground one right after the other. (looking at the soil and deep tracks, together with a side slip hard landing, and it would have lost a lot of energy where it met the ground) You can then "place" the MD on the ground at the beginning of the 3 tracks. You will see that the angle the MD80 is pointing to is not the travelling direction of the main gears.

3. If the nose came down with a pronounced nose right slip, you can imagine the nose gear's initial contact would come offset. Looking at the part where people beleive is a burnt part of grass it can also be said that the nose gear chomped into the dirt and flung a lot of dirt towards it's initial track (thus to the left) the same direction the tail cone rolled off to.

I can totally envision this form the foto's and tracks. Please pardon my computer aided design but this is what I envion...



the orange tail strike first and rolls in the initial track over the ground. However the drift (given in blue) is significant, when the nose plummets to the ground in the odd angle it spews dirt and/or hydraulics in the direction of travel (marked in red) this can also be seen where I beleive in fact the nose gear hits the ground. Due to the soft terrian and the slipping inpact, and the MD80 swerves around it's nose gear (drifting) for the few second it takes to reach the embankment.

Xander

[ExSp33db1rd]

Great graphics ! How d'you do that ?

[PJ2]

Fine work, xkoote, that's exactly how I had imagined both the heading-changes and track of the aircraft to be. The track of the body of the aircraft "straightened itself out" given the trajectory of the mass and lateral forces at work; thus the 'S'-turning...

LuckyStrike, the area in the grass is that area about which I made my comment that the drag of the main gear would be too great for any (meaningful/sustained) noseup pitching. I agree with xander - the nosewheel "slammed" down and created the marks - not an engine.

By the tracks there are no high bounces of the airframe itself nor loss of the main-gear at least until past the road. Any significant bounces will have occurred before this point, on the runway, (if at all).

Also, (given eye-witness reliability and potential for over/under-estimating aircraft attitudes), the bank angle to sustain high drag forces sufficient to pull the aircraft heading to the right, would not have to be that high - I'm guessing between 10 and 20 degrees rt. bank at the most. But the recorders will tell us soon enough.

Re damage to the DFDR notwithstanding heat survivabilit, assuming either engine stayed with the airframe, there would have been electrical power until quite late, (relatively speaking) in the breakup sequence. There could very well be data for critical phases, say up to the first impact, remaining intact in the DFDR. We can certainly hope for this, anyway.

[Wirelock]

am i correct be saying the other item in the pic with the tail cone is 1 of the thrust reversers. a collegue said he had observed 1 stuck in the grass???

[el #]

Assuming the object pictured close to tailcone it is a reverser, would be correct to think that a deployed or moving reverser is more likely to separate than a locked one from the engine in case of tail shock ?

[PJ2]

wirelock;

am i correct be saying the other item in the pic with the tail cone is 1 of the thrust reversers. a collegue said he had observed 1 stuck in the grass???

I don't think so - it's too large. It could be an engine intake, however. Unfortunately the resolution of the photo is not high enough to discern. Having more, and higher-res, photos from the helicopter would be of great interest to all, I'm sure.

[el #]

Another consideration to make is that to leave such equal L/R marks, a/c must have been wing level when drifting on the grass. It appears that PF had managed to handle that aspect of the situation following a stall and wingtip contact, but he couldn't do anything more than that.

I'm honestly convinced the outcome would have been very different if the the terrain didn't featured such a plane-breaker ravine.
After all, if a plane stays intact in a crash, there is a chance that there will be no fire, that is the ultimate killer.

[theron]

its difficult for me to tell from the aspect of the photo, but dont you think the nose wheel and main gear marks are too close together for an aircraft with such a long "wheel base" (sorry if this is the wrong term, please correct me):

[md80fanatic]

When the aircraft made those tracks, it must have been traveling in excess of 130 knots or more. The nose wheel is not particularly effective at this speed while on pavement, and should be even less effective off of it. For the nose wheel to remain in a visible straight line while all else rotates around it, would take incredible energy (proportional to the distance between the nose wheel and the actual center of rotation of the aircraft). I imagine the spoilers being out...adding to the weight felt over the mains and contributing to the lightened nose. The nose wheel was probably physically on the ground, without enough down force to leave any track (or to affect the lateral handling of the aircraft).

[xkoote]

That means that although it swerved you shouldn't expect wild giration on that piece of grass. Beleive me that is a short distance for an MD80 travellen in excess of 100 knots. Probably a quick swerve and correction before going down the edge. I guestimate he wasn't on there for more than 5 or 6 seconds.

Xander

[lomapaseo]

That means that although it swerved you shouldn't expect wild giration on that piece of grass. Beleive me that is a short distance for an MD80 travellen in excess of 100 knots. Probably a quick swerve and correction before going down the edge. I guestimate he wasn't on there for more than 5 or 6 seconds.

Xander

How does one command an aircraft to swerve like that?