pasoundman

Depends on a/c type but on your average twin jet, not a lot - just a modicum of rudder to keep straight and obviously not as much retardation as you'd have if both reversers were working.

pasoundman
 

A "locked out " reverser really is not a massive issue.

We don't even consider the retardation effect of reverse thrust if we are using a dry runway for takeoff, and even on an aircraft like the 747, which I guess has far more potential for assymetric thrust handling issues than an MD, we on occasions operate with one reverser locked out, even an outboard one. It does lower our landing cross wind limit and you are aware that the aircraft is slightly assymetric when reverse is applied but a correctly locked out reverser it really isn't a significant issue.

(edited to add that fireflybob beat me to it)

All fair and well if one anticipates using the reversers and it is know one is deactivated or if one fails to deploy when selected. However, it is a different situation when a reverser deploys uncommanded. Factors such as in which phase of flight this occurs and how much time is available to correct the situation, if the situation is identified as such when time is critical, come to mind.


Green-dot

Green-dot
 

"It is a different situation when the reverser deploys uncommanded".

Agreed - but as I read it that wasn't the question pasoundsman asked... and it wasn't the question fireflybob and myself were answering...

I thought we were addressing the issue of reversers being locked out?

FDR and CVR were certainly screened for systematic failures days ago. If indications of a systematic mechanical or electrical failure had been found the MD operators would have been alerted by an all operator telex. As this is not the case until now such failure may not have been found.

"
I can't remember another MD-82 accident at Madrid, apart from the latest one.
25 years ago an Aviaco DC-9 collided against an Iberia B-727 in the ground, due to intense fog, and the report is available since many years ago also.

Are you sure about if it was at Madrid ( LEMD / MAD )?.

BR

Dear sirs,

First of all, sorry about my poor English.

We're only sure about what happened, I mean the sequence of the facts.

But now, we can't really know the reason of why the EC-HFP crashed almost two weeks ago.

It's impossible. We can only do suppositions.

Please dont forget that until the last moments of the flight JKK 5022, your collegues were fighting against the impossible task of controling that "wounded " plane in its final run .

Don't forget him. They were good and skilled pilots, many of your Spanish collegues, said that. People who flew with him in several situations.
Also the same for the rest of the that good crew ... and the passengers of course, the main reason why we're here now.

Think like pilots and try to imagine what happened inside that cockpit ... like pilots. Don't doubt about your colleague's capabilities or competence first.

Also the same related to the technical staff of Spanair.

We're are here ( many of you as pilots, in my case in the side of the ATS engineering ) to reinforce the safety of the operations, learning about what happened and be aware about how to avoid it ... in the next time in every link of this "safety chain". This must be our first thought!.

Best regards

Ferrobus;
Your English communicates just fine.

Thank you for your post which is a very important one to all readers of this thread but especially flight crews who do this work.

We may be almost certain that your colleagues were of the highest professional standard and highly skilled aviators.

I say this not in "automatic defense" of colleagues and certainly not in flattery or comforting but in another way. This is an important flight safety point that you have made.

While already understood by most, it is very good to remember that each one of us could find ourselves in the same circumstances and that these pilots were doing their very best to save their passengers in the few seconds they had.

There is sometimes a quiet thought that perhaps a crew "wasn't good enough" or that some other reason resulted in a "sub-standard" performance. It is my experience, and I am assured by other safety people and experienced accident investigators as well, that this is rarely true.

Instead, very good, high-time, experienced pilots with whom no fault may be found in their records or personal lives can find themselves in these circumstances, sometimes beyond their control, sometimes within it.

In other words, these pilots were just like you and me.

A number of posts on this thread have said this in other ways and other posts have discussed "cultural" issues, "human factors" and so on. These are very important areas of discussion among flight crews and airline managers alike. We know now that most accidents are the result of systemic causes and not just one isolated mistake.

Because aviation safety is highly-resilient, it tolerates mistakes by many people almost all the time but sometimes all the barriers are broken through and an accident happens.

With the help of serious professionals who know their own fields well enough to enter a collegial dialogue respectful of others' professionalism, those who fly airliners for a living come to PPRuNe to talk about and maybe even find out what happened to their colleagues.

Thank you for your post, sir.

PJ2

Sorry about the long time ago comment. It has only been a couple of weeks but it seems like a long time to have no information that must be available.
I tried to delete the post before it posted but it was too late. Most crashes like this get preliminary information but for some reason this one leaves us wide open to speculate on flap settings , reverser deployment and thrust settings that the FDR has already answered. Why keep it a secret?

PJ2

Well said.

Whatever happened to this a/c and it's crew could have happened to any of us.

If they could screw up- so could any of us.

If it was a mechanical failure- it could happen to me or you tomorrow.

I wish they'd put out some sort of interim report mind, they must have an idea by now FFS!

At least it'd save a lot of prune speculation!

NOT thrust reversers or engines !!!
 

Let's not get off the track:

I think we will find that:

THE THRUST REVERSERS didn't cause or contribute to the crash.

The ENGINES were producing proper and normal thrust for takeoff.

And that my theory is correct, somehow the flaps/slats were not extended and that the takeoff configuration warning/groundshift mechanism were compromised...the symptom being the heating of the RAT on the ground.

AND WE ALL MUST CHECK THE KILLER ITEMS prior to takeoff!

It has been a generation of time since the Detroit crash...but it happened again. We , as pilots, must keep an instutitional memory of the past crashes in order to avoid future crashes.

sevenstrokeroll - you may be on the right track.

As sad as is, it may just be the chain of events and failures (technical, sop, fatigue,...) leading in an attempt to take-off a perfectly airworthy aircraft in clean configuration.:(

Into the equation don't forget an engine birdstrike or compressor stall may have delayed the take off roll.

Speculative Conclusion
 

Sevenstrokeroll:

This is certainly AN explanation, maybe even the most likely explanation but, unless you have sources inside the investigation, not based on any known facts.
If we could confirm that the deactivated TR was on #2 engine and that the picture of an engine with TR deployed was the #1 engine, then the uncommanded TR deployment theory would be less valid. But we can't, so it does remain a possibility.
This thread needs more hard facts which, probably will not be available until, in accordance with Spanish law, the first official report is made after a month. The lack of information leaked to the media suggests that the investigation is being well managed so we will just have to wait.

It should be part of any type acquaintance training if it is not. Shouldn't it? Isn't it?

threemiles:

no, it isn't and yes it should be.

training all over the world (with some exceptions) is confined to what is needed to pass the rating ride.

it is up to the individual pilot to be a better pilot by learning on his own.

and to the above:

a deployed thrust reverser won't bring this plane down if properly handled by the crew.

Type - issue - memory
 

The industry "memory" about any issues with the different types is actually rather good. In most countries the data is freely available to pilots who want to know. In the UK, the Belgrano's data unit is v. good and can be v. helpful

Sure, if they;
1. KNOW the reverser is deployed and
2. Act VERY fast within a few seconds.

In this case, the right reverser was deactivated and stowed with wire.
What panel indications would they get if THIS reverser deployed?
My guess is not much - if any.. .

XPM

Don't forget climatological and geographical conditions ( High temperatures, tail wind ).

Keep on mind also that the plane skidded out of the runway with more than 1000m of runway ( displaced threshold 18R ) available in front.

Dear pilots,

How deadly is not setting flaps/slats? I have read if I am not mistaken on this thread that some (in 737??) have taken off with incorrect settings.

What I am getting at is considering the number of flights per day, is this something that happens unplanned often (daily, weekly, monthly???) with planes using a good chunk more runway but still getting just into the air, or is this a near certain crash situation. As a follow up, is the MD more or less tollerent of this situation than other aircarft?

What I am following with these questions are the possible human factors. This morning I was in the shower and half way through the shower I could not remember if I had already shampooed. When we do something every day in the same 'context' it is natural that we may falsely remember doing something or become confused and 'skip' a set of actions and not realize it. I know checklist protect agaist that, but mistakes can still happen.

Human factors are very hard to overcome, and if this accident was caused by such factors, what else could be done to prevent a repeat?

Thanks,

TM