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-   -   Spanair accident at Madrid (https://www.pprune.org/rumours-news/339876-spanair-accident-madrid.html)

wileydog3 21st Aug 2008 15:40

Onepost only

wileydog3, it doesn't sound like they tried to land back though. I don't think it was a case of not following procedure and landing back (after V1, passing V2, sub V2, or whatever speed/phase they were at!!) more than losing control after a serious failure(s). All this from reports on here though, but it doesn't sound like a re-land attempt. The talk of “rolling” and “one wing tip striking the ground” etc etc. Sure they were doing their best to follow procedure and get it into the air!
You make a point but then we have more things to explore. If there was an over-rotation, they would be getting a stick shaker normally at what? 1.15Vso? It's been a while since I had the privilege of flying the -80 so I don't remember what the shaker was calibrated for.

But again, some of the posts suggest the suspension of reality and the inherent and desire for self-preservation. The crew did not intend to crash and thus we have to begin asking why they acted/reacted as they did.

I may have posted this but I like Dekker's comment that cause is not found, it is constructed and to even construct a plausible cause, we have to get inside the 'tube' to try and ascertain what the crew was seeing, what the crew was thinking and how they were responding to the events.

No doubt, some one will come along and say they should have 'connected the dots' but that short changes the process and is afforded the bright light of hindsight. I also like the observation that during the evolution of an event, the process is fairly opaque and afterwards starkly evident.

Feathers McGraw 21st Aug 2008 15:41

Gents

I really hate to say this, but how do you all think that you can maintain the sanctity (assuming that is what you really want) of PPRUNE in the face of the increasing access that everyone has to virtual forums of this nature? If the nonsensical speculation doesn't appear here, it'll pop up elsewhere and still the press will seize on it and print it or air it to get their few moments of fame.

Many years ago, when Usenet news was limited to a very thin slice of society because access was hard to come by, it was a very useful place where the contributors were knowledgeable and would nearly always know the answers immediately. Once internet access became common, this state of affairs began to disappear, eventually reaching the point where it became necessary to trust people because you knew their style and decided on whether to take any notice of them. It's no different here, really.

Do you really think that clearing out the non-aviators (and I'm one, but still an engineering professional) will help? And do you really think that the majority of people tar all of you with the brush of the clueless that appear here?

Not at all, many of us read and learn and post rarely. It's in sad circumstances such as this that we all come in the hope that we'll learn things that the mainstream news organisations are simply unable to tell us.

You already have your company specific forums where proof of employment is needed to participate, please don't withdraw from engaging with those of us that celebrate the whole business of aviation even though through one reason or another we were unable to participate ourselves.

PPRUNE is an extraordinary place and is simply the first choice of anyone that is seeking information on aviation, and we're amazingly good at ignoring the unfounded speculation that appears in a thread such as this.

Thanks for listening.

Munnyspinner 21st Aug 2008 15:42

Fireflybob - wings full of inflammable explosive
 
That'll be the problem then!

Last time I looked Jet A1 was not classed as an explosive. Perhaps fuel vapour mixed in the right ratio with air is potentailly explosive but, generally, one has to go to a fair amount of effort to get it to burn - that's what a gas turbine does!

In a catastrophic accident then spilt fuel does have a tendencey to ignite becuase it has been vapourised by force and there are numerous ignition sources.

If I find the fuellers have been filling my a/c with exlposive I will have to think twice about flying!

airship 21st Aug 2008 15:46

Too many cooks (mods) spoil the broth...?!
 
PPRuNe Towers
Dep Chief PPRuNe Pilot
(IC Lavs & Dunnies) wrote:


Depending on your personal settings most of you will see 20 posts on the first page of this thread.

However we can see 37, an indication of how the 4 mods working this forum yesterday were cutting away the breathless pack.
I believe the default setting is that there are 20 posts which appear on each page of every thread. Does this mean that the cooks (mods) miraculously conjured up another 17 posts? :confused: But hey, wouldn't it be fun to know that whilst 1 mod was deleting a post, another mod was reinstating it, another was censoring bits of them and another complaining to the EU's human rights commission - if you get my inference...?! Oooooh, a battle of the PPRuNe mods (I mean't cooks) - this should be fun (I can't remember the last time but I'm sure it's all happened before - but maybe only in JetBlast)...?! :ok:

Caudillo 21st Aug 2008 15:49

For what it's worth, TVE - the Spanish equivalent of the BBC appears to have some pretty authoritative information on its website. In Spanish naturally.

The Transport Minister (roughly) Magdalena Alvarez has confirmed that the aircraft was airbourne, at 200ft when this happened.

TVE reports that the left engine fire and failure was uncontained. Cites sources from their CAA saying that debris from the left engine damaged the rudder and/or the right engine, causing uncontrollability, veering to the right and the crash.

Dairyground 21st Aug 2008 15:51

Has the eyewitness account translated in post #202 been authoritatively discounted? The claim is that the aircraft was throwing up sand from off the left hand side of the runway and that the right wing then struck the ground, with the aircraft then disappearing off to the right.
This would seem to be consistent with an initial swing to the left on losing power from the port engine followed by an attempt at recovery that was hindered by impaired directional control.
If, as has been reported more recently, the aircraft became airborne, impaired yaw control may have indicated that an attempt to land on the remaining runway was the least worst option.
Perhaps those guys were just a few metres sideways from success.

Flight Safety 21st Aug 2008 16:08

Caudillo, if true, there was probably nothing the pilots could have done.

Frangible 21st Aug 2008 16:08

Apologies to mods and Danny.
I realise now how much crud you must be binning.

PJ2 21st Aug 2008 16:08

wileydog3;

I may have posted this but I like Dekker's comment that cause is not found, it is constructed and to even construct a plausible cause, we have to get inside the 'tube' to try and ascertain what the crew was seeing, what the crew was thinking and how they were responding to the events.

No doubt, some one will come along and say they should have 'connected the dots' but that short changes the process and is afforded the bright light of hindsight. I also like the observation that during the evolution of an event, the process is fairly opaque and afterwards starkly evident
Precisely - I think Dekker's work has much to contribute generally in terms of how humans interpret the world and history, but in both accident prevention and investigation specifically. His 2nd latest, "The Field Guide to Understanding Human Error" 2nd ed, (his latest, "Just Culture: Balancing Safety and Accountability", January 2008) are both worth reading and not just for aviation professionals and accident investigators.

I would commend many of the contributors here to these books alone, for comprehension of the investigative process and a more thorough understanding of human nature, and not only in aviation.

If nothing else, Dekker makes clear the strong human motivation to re-write experience to be in accord with post-event learning, while those involved in the event are only faced with perhaps dozens of avenues in terms of choice and dozens of "cues" which afterwards assume are so clear.

SeniorDispatcher 21st Aug 2008 16:11

I was driving crosstown back in the mid-1990s after adminstering an FAA exam, and news of TWA 800 broke on the radio. That it was TWA 800, JFK-Paris, and that the aircraft was down in the water off Long Island were all factual points, and it took less than 30 seconds of listening to get them, at which time I turned OFF the radio. I did so because I knew what would follow (in the absence of other "facts" yet to be determined) would be endless blathering and idiotic speculation and contradictory information in order to fill-up otherwise dead broadcast airtime, as is typical within he first 24-48 hours of any major aviation accident.

Like some others, I also wish there was an effective way to "turn off" PPRUNE from being a vehicle for such 99% nonsensical and speculative comments before the wreckage had even cooled, but I don't know what the answer is on how to best accomplish that.

Kudos to Danny, Duck, and the others who have taken the time to cull that kind of stuff from the thread.

foresight 21st Aug 2008 16:14

Feathers McGraw
 
Really annoyed! I was mentally composing a post when I find that Feathers McGraw has stated my case far more eloquently than I could have done.

Any intelligent layman will be able to sort the wheat from the chaff. There is enormous value in providing access to information and opinion when the media let us down so badly. There are genuine non aviation people who want a feel for what it is all about. If a post annoys you, then stay professional and don't rise to the bait.

Incidentally I have 1200 hours on MD80's (long time ago) but feel no need to offer an opinion - there is simply not enough information to hand

PJ2 21st Aug 2008 16:20

Flight Safety;
If I may,

Caudillo, if true, there was nothing the pilots could have done.
Quite possibly - we'll know in due time of course, assuming the recorders survived the fire. But I would like to offer the notion that many, many statements are tautologies in the sense that the conclusion "proves" the initial statement. I believe informed speculation is worthwhile, if not cathartic for a few, but we know that much will be settled when such speculation ends and the investigation begins, with data, possible video from airport cameras, the CVR and DFDR, (any FOQA equipment, if Spanair was doing a flight data program likely would not survive). It may indeed be the case that the situation deteriorated so rapidly that the crew was along for the ride - a number of legitimate scenarios have been posited (Northwest MD80 at Detroit, reverser unlocked, catastrophic engine failure accompanied by hydraulic system failure and loss of rudder power etc etc). It seems that the aircraft had lifted off by many reports which would explain, along with terrain characteristics, the nature of the break-up but I suspect these would all be after the initiating event.

foresight;

Any intelligent layman will be able to sort the wheat from the chaff. There is enormous value in providing access to information and opinion when the media let us down so badly. There are genuine non aviation people who want a feel for what it is all about. If a post annoys you, then stay professional and don't rise to the bait.
Very well stated. While difficult to endure at times I think keeping the forum wide open to all is best and what you say will happen. We're not going to solve this or any accident here but frank (sometimes very frank) professional discussion enlightens, educates, and provides comfort for some who may be casting about for anything that intelligently explains their experience. As for the punters, so far, it's a free forum and inappropriate posts can be ignored. The one issue is, it is abundantly clear that most who post statements that don't make sense have not read the thread carefully first and just shoot from the hip - tough to wade through.

FWIW...
PJ2

ECAM_Actions 21st Aug 2008 16:24

FWIW, someone posted this over at the MD80.net forums:

http://c.imagehost.org/0691/1219302341669.jpg

They note that it is in the fully extended position.

ECAM Actions.

dbee 21st Aug 2008 16:25

Awful; those few who escaped may still die from their injuries. From the pictures that I have seen, ( fuselage on its side) it would be virtually impossible or people to reach, let alone open, the emergency exits :* .............dbee

WhatsaLizad? 21st Aug 2008 16:25

Feathers McGraw,

That is my point regarding this situation. At the moment, PPRUNE can't exclude every ignorant poster.

My suggestion is one thread for the endless naive questions and suggestions, and have another thread where those with relevant aviation experience that are requested to have their qualifications noted first on their posts.

That way those of us in aviation can ignore the undeducated thread and participate on the "experienced" thread about any incident.


Just a suggestion.

crewcostundercontrol 21st Aug 2008 16:34

WhataLizard

I agree, I think PPRUNE is fantastic for those of us in the industry. If someone could start a new formum website for Pofessional pilots only, with some kind of vetting then I would sighn up today. This place is now full of armchair experts and spotters. I know it has been talked about before on here but it would be nice to have a CPL/ATPL only forum to cut out the crap.

wileydog3 21st Aug 2008 16:36

PJ2. I would also recommend the book by R. K. Dismukes, B. A. Berman, & L. . Loukopoulos (2007) The Limits of Expertise: Rethinking Pilot Error and the Causes of Airline Accidents, Ashgate Publishing Company

Sometimes there just isn't a solution or if there is a solution, there may not be enough time to implement it. For example, Nick Warner and the 1994 A330 crash at Toulouse. (From talking to a few people, Warner was considered not only one of the best but one of the VERY best.)

PJ2 21st Aug 2008 16:37

ECAM_Actions;

Thanks for posting this.

Whether the reverser was deployed before ground contact or during the breakup sequence can be determined in a number of ways - obviously the recorders, but also by traditional methods.

I haven't seen info on this..can any MD80 fleet type operators tell us if these engines are FADEC controlled? Tx...

bookworm 21st Aug 2008 16:40


Don't know much about flying MD hardware but here are the Metars either side of departure time of 1425 (presumably Zulu)
No 1425 local, 1225Z:

LEMD 201030Z 12003KT CAVOK 25/10 Q1019 NOSIG=
LEMD 201100Z 17002KT CAVOK 26/09 Q1019 NOSIG=
LEMD 201130Z 16005KT CAVOK 27/08 Q1019 NOSIG=
LEMD 201200Z 35002KT CAVOK 28/06 Q1019 NOSIG=
LEMD 201230Z 18007KT 090V240 CAVOK 28/02 Q1018 NOSIG=
LEMD 201330Z 19007KT 110V240 CAVOK 30/01 Q1018 NOSIG=
LEMD 201400Z 24003KT CAVOK 30/02 Q1018 NOSIG=


Could cross wind component be approaches/exceeded in TO roll?
So it seems unlikely that wind was a factor -- though of course a METAR is just a snapshot and you can't be 100% sure what was happening between.

PJ2 21st Aug 2008 16:41

wileydog3 - thanks, will pick it up; have recently ordered Just Culture. There is much here for airline managements as well as flight safety departments wrestling with limited resources and how best to focus them as SMS is implemented.
I always thought that CRM was as good for a marriage as it was for the cockpit... ;-)

Cheers,
PJ2

bardos 21st Aug 2008 16:41

from the spanish newspaper "el mundo"
 
Los dirigentes de la aerolínea Scandinavian Airlines (SAS), a la que pertenece Spanair, han justificado el despegue del avión siniestrado ayer en una multitudinaria rueda de prensa celebrada en Madrid. No obstante, admitieron que el avión presentaba un problema de "calentamiento excesivo en una toma de aire", que fue "aislado" y, posteriormente, la nave "fue despachada para el vuelo".
Ante la pregunta sobre si aislar el problema significa solucionarlo, el subdirector general y director de producción de Spanair, Javier Mendoza, aseguró que hay distintas formas de tratar el problema y que, en esta ocasión, "se aisló el sistema quitando el interruptor que le da energía".
Mendoza afirmó que "ésta es una condición que es aceptable para el vuelo y es una práctica normal. Hay un documento que es la lista de equipos mínimos que refleja esta actuación". Por tanto, según estas explicaciones, la avería no fue totalmente reparada, sino "aislada".


In a massively heavily attended press conference in Madrid, the Management of Scandinavian Airlines (SAS), to which Spanair belongs, has justified the take-off of the crashed airplane. Nevertheless, they admitted that the airplane had a problem with “over-heating in an air-intake valve”, which was “cut-off” and then the airplane “was sent on its way”.

Faced with the question of whether cutting off the problem means fixing it, the assistant general manager and production manager of Spanair, Javier Mendoza, maintained that there are different ways of dealing with this problem and on this occasion “the system was cut off by turning off the switch which gives it power.”

Mendoza stated that “this is an acceptable flight condition and is normal industry procedure. There is a document which is a list of minimum equipment requirements which supports this action”. Therefore, according to these explanations, the breakdown was not completely repaired, it was “cut off”.

Groundbased 21st Aug 2008 16:41

All,

I have been reading Pprune for the last 5 years in order to build up knowledge of something I find fascinating. I've enjoyed the technical debates on Tech Log and many of the other forums along with R and N.

I've always felt that when the "no amateurs" discussion has surfaced that I should support not banning them. After all, I read to learn, and if I feel I can frame it in suitably knowledgeable terms I would post a question or a view if relevant. surely others are the same.

Regrettably reading this thread I have changed my view. The uninformed rubbish that has been posted here defies belief and obscures the pertinent and knowledgeable content that has been contributed.

I believe you are right and some method must be found to return this board to what it was 5 years ago when I first, joyously, discovered it. I just hope that some way can be found that I may continue as "read only" on these fora (but still contribute to Jet Blast!).

DozyWannabe 21st Aug 2008 16:46


PJ2:
can any MD80 fleet type operators tell us if these engines are FADEC controlled?
Not an operator (or even a professional pilot) but I'm pretty sure the answer is no. JT-8D-200 series aren't, as far as I can remember.

And as for the "ban all non-pilots" calls, is it really worth potentially throwing out many babies with the bathwater for the sake of not having to put up with a bunch of idiots for a couple of weeks a year at most?

ECAM_Actions 21st Aug 2008 16:46

The MD-82 doesn't have FADECs - it uses mech linkages to fuel control valves and other assorted bits.


General

The airplane is equipped with two axial-flow, bypass, turbofan Pratt and
Whitney engines. The JT8D-217, -217A and –217C (-219 operated as -
217A) engines have a normal static takeoff thrust rating of 20,000 pounds
and a maximum takeoff thrust rating of 20,850 pounds.
An automatic reserve thrust (ART) system is installed. In the event of an
engine failure, the ART system, when operating, increases the thrust on the
remaining engine.

Each engine is equipped with an acoustic treatment in specific areas for noise
suppression. The engine nacelles are supported from horizontal pylons by
vibration-isolating side mount systems. The nacelles are isolated from the
fuselage by a firewall within the pylon and by a secondary fireseal at the
pylon fuselage interface. To provide additional protection, the secondary
fireseal extends above and below the pylon on the fuselage surface. To
achieve necessary nacelle compartmentation, a fireseal is installed aft of the
rear engine mount, which provides separation of the accessory compartment
from the reverser section. The nacelle ventilation system is designed to
provide adequate cooling of engine and accessories and to prevent
accumulation of combustible mixtures.

For monitoring engine operation, an EPR (engine pressure ratio) gauge,
thrust rating indicator, N1 and N2 tachometers, EGT (exhaust gas
temperature) gauge, FUEL FLOW gauge with a FUEL USED readout, oil pressure
gauge, oil temperature gauge, and fuel temperature gauge are provided for
each engine.

The left and right engine EPR gauges receive sensing signals from the
respective engine air inlet pressure (Pt2) probe and the low pressure turbine
discharge pressure (Pt7) probes. Engine pressure ratio (Pt7/Pt2) is a measure
of thrust being developed by the engine that is displayed on the EPR gauge.
Power to operate these gauges is provided by the respective AC bus.
The thrust rating indicator is interfaced with the ram air temperature probe
and digital flight guidance computer (DFGC) 1 and 2. Ram air temperature
(RAT) and EPR LIM (limit) are displayed on the indicator. Mode buttons are
provided on the indicator for selection of desired mode (T.O., T.O.FLX, GA, MCT,
CL, and CR). The DFGC’s supply data to the indicator for automatic display
of EPR LIM for mode selected.

The left and right N1 tachometers indicate the respective engine low-pressure
compressor rotor RPM as a percentage. The left and right N2 tachometers
indicate the respective engine high-pressure compressor rotor RPM as a
percentage. Power to operate these gauges is self-generated.

The left and right EGT gauges indicate in degrees centigrade the temperature
of the exhaust gas of the respective engine. Each gauge receives signals from
temperature probes located in the exhaust gas path of each engine. Power to
operate these gauges is provided by the Emergency DC bus.

The left and right FUEL FLOW gauges indicate the rate of flow in pounds per
hour that fuel is being delivered to the respective engine. A FUEL USED
readout on each gauge displays a digital readout of fuel used in pounds by the
respective engine. A FUEL USED RESET switch is provided to reset the FUEL
USED readout on both gauges to 00000. For further description of FUEL FLOW
gauge/FUEL USED readout and FUEL USED RESET switch, refer to Fuel section.
Power to operate these gauges is provided by the respective AC bus.
http://c.imagehost.org/0739/reversers.jpg

HTH.

ECAM Actions.

lnav-vnav777 21st Aug 2008 16:49

any news from the crew?

Litebulbs 21st Aug 2008 16:51

If it was an uncontained engine failure, then it is luck, not aircraft design that makes an event either an incident or accident. It matters not, whether the control surfaces are hydraulically or mechanically actuated. If a piece of engine decides to pass through a hydraulic pipe(pipes) or cut a control cable(cables), the result is the same, reduced or no control. Put that at or around V1, Vr or climb, then it is down if the pilot flying to use every ounce of their training and experience to attempt to recover the situation.

Passenger aircraft are not designed to contain within its systems and controls, an uncontained engine failure. Thought and design goes into system redundancy, but you do not fire bits of hot engines at airframes and see what happens if?! You cannot predict which bit of engine will not be contained and where it is going to travel after it has left the engine casing and cowl. That is why engines are designed and tested to contain engine failures.

Now, why did it fail? I do not have authorisation on the MD82, but jets are jets. They all use the laws of physics to work. I am making an assumption, so please feel free to flame me, but from what I gather from previous media statements is that their was a problem with a sensor that is used by various systems including thrust management, to derive a temperature. If this temperature was inaccurate, or missing, then it is possible that incorrect thrust settings could have been used or manually calculated, with a possible outcome of an over boosted engine. There would obviously be other parameters to watch such as engine temperature or N speed, but this could be just another hole in the cheese. The engine could have been on watch, with degradation being "on condition" monitored by repeat boriscope inspections, which would normally be OK within its normal operating margins, but on this day, it failed at precisely the wrong time.

Lessons will be learned and god bless the people who have lost through this terrible event.

ChristiaanJ 21st Aug 2008 16:58

lnav-vnav777,
See post #351.

Guy D'ageradar 21st Aug 2008 17:01

RoyHudd, Aileron Drag et al shame on you.

Perfect example of the elitist attitude that unfortunately also tars the image of your more open minded colleagues. I don't know if you've looked down from your pedestal recently but FYI pilots and engineers are not the only professionals involved in aviation. I think you'll also find that a large amount of the spam on this thread was contributed by some of your fellow super-human beings.

Get a grip. :ugh:

BenThere 21st Aug 2008 17:02

I've only been flying multi-engine jets, and making a living at it, for 32 years, so obviously I have much to learn. In fact, I've barely scratched the surface of all there is to learn about aviation.

But it seems to me that those who complain loudest about non-pros have the least to offer themselves. They are first to denigrate, last to contribute to the discussion, IMHO. I see it as a manifestation of insecurity or inadequacy when one resorts to insults and ridicule, but that's just me.

I welcome all inputs, from pilots, engineers, passengers, and the simply curious, and will decide for myself whether or not to take in the message or reject it, thank you.

This incident has given me a lot to think about as I set out on my next trip tonight. These pages have provided insight regardless of those who are put out by the non-technical intrusions. If the press wishes to peer within Pprune, more power to them. I hope they, too, can separate the chaff from the informed opinion. If a journalist takes it upon himself to read the entire thread, he will come away with a better perspective. We have nothing to hide, therefore why the concern about spies?

Wodrick 21st Aug 2008 17:06

Post 431
 
Thrust Reverse operation is inhibited by A/C not on ground.

ECAM_Actions 21st Aug 2008 17:08

BenThere - I couldn't agree more.

The press are capable of spouting rubbish without reading a darn thing on the subject.

Can we get back on topic, please?

ECAM Actions.

Feathers McGraw 21st Aug 2008 17:09

Thinking a little further, I wonder if Danny and co could arrange for a little "verified industry insider" icon to appear alongside ones login ID and also provide the ability to only see posts from the so verified PPRUNErs if desired.

That way, you get to choose what you see and respond to.

As to the comment about this thread changing the view as to whether non-aviation types should be allowed, I thought it was no different to the initial BA038 thread in this regard.

Actually, learning how to recognise and ignore the clearly ill-considered from the knowledgeable is one of the small enjoyments of this sort of place. But it does mean you need the time to read and digest.

Double Zero 21st Aug 2008 17:10

' Passenger aircraft are not designed to control ( substain or constrain, my words ) ' an engine failure ?

Unless very unlucky with the hot end disc, I really reckon they ARE...

Yours, airmchair pilot and experienced ( fighter ) test & development team member, who obviously ought to be chucked off this site for not being a 757 etc aircrew -

In the brief time I have left before being buried in 'Jetblast',

How many actual airliner aircrew / airliner engineers & designers agree about ' containment' being designed in - though a few instances lately seem to indicate it is still a goal rather than achievement ?

skyken 21st Aug 2008 17:23

I smell a RAT
 
Ram Air TURBINE has nothing to do with temperature.

Litebulbs 21st Aug 2008 17:28

Double Zero -

Using your words, you are correct. Using my word "uncontained", then I will stand by my understanding of aircraft design.

BeechNut 21st Aug 2008 17:28

On the pro vs non-pro debate. Obviously I am not a pro. I am a PPL who loves all aviation. While only a 600 hour PPL, I am current and own my own aircraft. I strive to operate it in as professional a manner as possible, and I have much to learn from the pros here. While this accident bears little resemblance to what can happen with a Beech C23, nonetheless I think all pilots can learn from every accident, even if that lesson is simply to never take things for granted.

That, and I have a sentimental love for the DC-9 series; many many hours as SLF aboard one, including in the jumpseat when such things were allowed, and my first ever jet flight (and second ever airline flight) was in a DC-9, as an 11 y.o kid way back in the late 60s (the outward leg was a Viscount...).

That said, many here, I have noticed have engineering/science backgrounds in non-aviation fields (I myself do in physics and chemistry, and vibration analysis). They can bring interesting info to table provided they, and we, understand the limits of their knowledge. This can be particularly useful in the Qantas analysis, regarding the storage of high-pressure gases and the physics an chemistry of the gas in question.

Lastly, with regards to lurking journalists, I would hope that perhaps some of them will actually gain a bit more appreciation for the complexities of aviation, and will at least learn to get basic facts correct, such as not confusing a stall with an engine failure (which happened in Canada's national newspaper recently). Also, they might learn how and where to search for data before making inane comments about the safety of a particular aircraft series that in fact has a pretty normal safety record. One hopes...

'nuff said, back to reading what the pros have to say.

forget 21st Aug 2008 17:30

Skyken, Total air temperature (TAT) is also called: indicated air temperature (IAT) or ram air temperature (RAT)

There's a discussion on smartarses like you in the last few posts. Please read them.

sevenstrokeroll 21st Aug 2008 17:32

skyken:

I mentioned RAT...and said NOT ram air turbine in this case.

RAT can also mean "ram air temperature". I asked if the MD80 had a Ram Air Temperature gauge or a total air temperature gauge. I flew the DC9 and it had a Ram Air Temperature and it might have changed with the MD80.

Just like TR can mean thrust reverser

it can also mean transformer rectifier

(or teddy roosevelt for that matter).

ChristiaanJ 21st Aug 2008 17:32


Originally Posted by skyken
Posts: 4
Title: "I smell a RAT"
Ram Air TURBINE has nothing to do with temperature.

Oh dear, I almost start to feel sympathy for all those arguing for a professionals-only forum....

Yes, 'RAT' can refer to a 'Ram Air Turbine', as on Concorde.
In this case it refers to a 'Ram Air Temperature' sensor, which is simply another term for a 'TAT', i.e., 'Total Air Temperature' sensor.

Were your three earlier posts of the same calibre?

CJ

PJ2 21st Aug 2008 17:55

ECAM_Actions;

Superb descriptions/schematics from the book, thank you. I suspected the installation wasn't FADEC-controlled but wanted to be sure.

delorean79;

Can a Pilot deploy full reverse on flight, flying a MD80?
While a few aircraft designs in the past (DC8, Convair990) could deploy reversers in the air, no present designs are certified for this and therefore either mechanically or through software or combinations of both, prevent reverser deployment in the air.

That said, I know of at least one DC9-32 series, (not an MD80 series) where it did occur at cruise altitude and we know of the Lauda Air B767 accident which was apparently a FADEC fault. Most fleet types have an emergency drill (memorized...) for reverse deployment in the air. The drill usually involves appropriate rudder input, (foot/rudder pedal in the kitchen and then some), ensuring directional control, and shutting the engine down. FADEC-controlled engine designs on the Airbus (CFM56 installations and likely others) command IDLE thrust if a reverser-deployed signal is sensed in the air.

That also said, most AOMs caution that controllability is a significant issue. For the record and for knowledge of non-pilots, going around after reverse is selected is absolutely prohibited. An accident (PWA B737, Cranbrook BC) led to this warning for crews.

NOTE: None of this post or discussion is to be taken as speculation that a reverser was deployed in the air as a possible cause. This is simply not known. This is only an informal professional discussion on the operational aspects of reverser deployment in the air to which crews are trained to respond.


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