Polish President and wife killed in Tu-154 crash

[justLOT787]

This probably divided you and the country is not looking like fools you are! So In your mind 50% of Poles are fools because they think Russians did it? I bet your parents and grand parents think it was the Russians fault? And you think you are smarter than 50% of Poles? People like you that see thing one way loose every thing! And for those who don’t know any thing about Poland then don’t comment!

Above comments are my own personal views! It's not the whole countries! And this did not divide the great country, the media and politics did! You will always have some people supporting theory A and some supporting theory B or C This forum is a discussion about the accident and every one discusses this accident and with some emotion and gives their opinion on it! This doesn’t make people fools it makes you a fool for just seeing one way. And maybe Polish people act harsh towards blaming Russians it's because of the two countries history! I read some where that to understand Poles and Poland you have to go back in history and do your research!

[Peter Kesternich]

(...) And you think you are smarter than 50% of Poles? (...)

Well - just because a majority has an opinion about an event that does not make it true. Neither in Poland, russia or any other country.

(...) This doesn’t make people fools it makes you a fool for just seeing one way. And maybe Polish people act harsh towards blaming Russians it's because of the two countries history! I read some where that to understand Poles and Poland you have to go back in history and do your research!

Well - going back in history, I think it is quite obvious why many Poles are paranoid about the Russians. But let's be realistic - Russia has nothing to gain by getting rid of President Kaczynski. It's not like he had any influence on Russian politics and being an EU member I think Poland should warm up to the fact that the EU has nothing to gain and much to lose by steering a confrontational course with Russia.

So - any conspiracy theories should be quickly shut down here. The most likely cause of the accident was that the president directly or indirectly pressured the pilot into flying into weather that the airplane and pilot were not equipped to handle.

[Evan]

So - any conspiracy theories should be quickly shut down here. The most likely cause of the accident was that the president directly or indirectly pressured the pilot into flying into weather that the airplane and pilot were not equipped to handle.

Sure. Unless President Kaczynski was a Russian spy, on a... suicidal mission to kill a big chunk of the Polish leadership by pressuring the pilots into this affair with a little John Wayne tantrum about cowardice... clever, those Russians.

justLOT787, do you know what 'minimums' are? Are you familiar with the term 'dive and drive'?

[Gabriel]

Even without going that far with the conclusion, what is absolutely clear now and completely proven is that:

The visibility in the field was very low (200m actual vs 1000m minimum required).
That fact was known to the pilot (the CVR shows the Polish crew of the previous plane that landed there earlier informing the pilot about this condition).
The airplane descended below the minimum permited altitude during the approach (the CVR has the flight engineer calling altitudes below the minimum)
The Russians didn't fabricate fog.
The Russians didn't force the pilot to go that far with the approach, they even suggested not to land and offered alternatives.

All that doesn't explain the accident, since now we have to understand why all that happened. But it does rule out any conspiracy (at least from the Rusian side)

[justLOT787]

All that doesn't explain the accident, since now we have to understand why all that happened. But it does rule out any conspiracy (at least from the Rusian side)[/QUOTE]

That is what I have been trying to say. We only have reports from the Russians! The Polish authorities are not allowed to do inspections or any reports. Russian government is doing what they want too and giving out the only information that they chose too. They are the ones who are in charged 100% in this investigation and believe me if this was even 5% Russian fault then they would cover it up. Just saying!!

[Evan]

That is what I have been trying to say. We only have reports from the Russians! The Polish authorities are not allowed to do inspections or any reports. Russian government is doing what they want too and giving out the only information that they chose too. They are the ones who are in charged 100% in this investigation and believe me if this was even 5% Russian fault then they would cover it up. Just saying!!

Did you even read the rest of Gabriel's post, or just the part you liked?

Have you considered that the Polish government is very reluctant to release the inevitable finding that poor command decisions by the president himself were to blame—that he is to blame for his own death and those of his staff—and will be looking instead for an opportunity to fabricate some fictitious, preferably Russian cause? I'll bet the Russians have thought of that. I think they are tightly controlling the investigation to protect themselves from any false accusations. When you consider the delicate relations between the two nations and the political opportunities this crash presents to certain Polish interests, I don't blame them.

And please understand, I don't have some anti-Polish or pro-Russian stance here. It's just so obvious that the Poles are to blame for this.

Google 'unstabilized approach', 'instrument meteorological conditions', 'minimum decision altitude' and 'positional awareness'.

...or better yet, read this:

https://flightsafety.org/asw/nov07/asw_nov07_p13-17.pdf

If, after reading this, you still blame the Russians for even 5%, I give up.

[Geebee]

This probably divided you and the country is not looking like fools you are! So In your mind 50% of Poles are fools because they think Russians did it? I bet your parents and grand parents think it was the Russians fault? And you think you are smarter than 50% of Poles? People like you that see thing one way loose every thing! And for those who don’t know any thing about Poland then don’t comment!

Above comments are my own personal views! It's not the whole countries! And this did not divide the great country, the media and politics did! You will always have some people supporting theory A and some supporting theory B or C This forum is a discussion about the accident and every one discusses this accident and with some emotion and gives their opinion on it! This doesn’t make people fools it makes you a fool for just seeing one way. And maybe Polish people act harsh towards blaming Russians it's because of the two countries history! I read some where that to understand Poles and Poland you have to go back in history and do your research!

Hold your horses.....
Don't take things so personally (in life). I never stated that 50% of the Poles are fools. I was not stereotyping rather making a - subjective, I agree - statement about the overzealous hypotesis that is being propagated here (aka the conspiracy). I don't want to offend you but maybe your knowledge of English is not up to par to make a distinction between 'to be a fool' and 'making a fool of yourself'. We all make fools of ourselves occasionally, don't we?

As mentioned by the others here, even if one would agree with your 5% chance of a conspiracy, one should not ignore the 95% person of factual information. Are you at all familiar with Occam's razor?

[Gabriel]

I want to share something that has been troubling me. Please note that most of what follows is based on different sources of different reliability, and then modified by my own analysis, so keep this with a grain of salt, ok?

- It was reported that they were following a glide slope. What glide slope? As far as we know, there was no ILS there.
- But it was also said that an instrument approach was set and reviewed in preparation for this flight. Was maybe some nav equipment installed there specifically for this trip?
- For this approach the minimums were established as visibility 1000m, DA (decision altitude) 100m.
- Russians use above-runway-elevation altitudes, instead of the above mean sea level altitudes we are used too. So 100m, if it was actually a DA, was 100m above the runway. That's quite an altitude for a decision altitude in a precision approach (typically 200ft), if there was one. For a non-precision one it's somehow low (typically 400ft).
- Now, a bit of rant about minimums in instrument approaches.
Non precision approaches have MDA, that's the minimum descent altitude. You can descend to that altitude and fly it until you see the runway and land or until you reach the missing approach point and go-around. You are not allowed to go below the MDA unless you have the runway in sight.
Precision approach (those with vertical navigation guidance like the ILS) have a decision altitude. You are supposed descend on the glide slope until the decision altitude. IF by then you have the runway in sight you land, if not you go around. Because the plane can't change from descending on the glide slope to climb in a split second, it's assumed that even if the go around is initiated at the decision altitude the plane will still descend a bit below that decision altitude before climbing.
A variation of the decision altitude is the decision height. It's the same than the decision altitude only that base on the altitude above the ground (AGL) as seen in the radar altimeter.
- If you use runway elevation for altitude reference, as it seems it was the case here, and the land is flat and level, then the altitude above the runway (as seen in the baro-altimeter) and above the ground (AGL, as seen in the radio altimeter) would be the same. But if the runway is atop of a 200ft cliff and you are approaching from the sea, the radio altimeter while above the sea will show 200ft more than the baro-altimeter set to show zero on the runway.
Pause.

It certainly looks that the crew had a lot of pressure to land, probably from the president himself.
The visibility was way too low, much lower that the required 1000m.
The tower informed 400m. The YAK Polish plane that had landed before also informed 400m, but later advised the presidential crew that it had deteriorated even further to what it looked like not less than 200m.
Still the crew decided to attempt the approach against the odds.

On the other hand, the crew mentioned that it looked like it wouldn't work,but that they would try it just once and divert if unsuccessful. They also briefed that the minimum altitude was 100m, and that they'd descend to that altitude and initiate a go-around if the runway was not in sight.

All in all, it looks like the crew wanted to satisfy the President in the attempt to land, but they were committed not to bust the minimums, and they were aware that a go around was the most probable outcome and they were prepared for that. Almost as if they wanted to say to the president "We tried, I told you it wouldn't work, happy now? Ok now where would you want to divert to?"

I have nothing against that. It combines satisfying an impulsive boss (keeping the job) while staying safe (keeping the life).

So what went wrong?

What if there was a mistake, confusing decision altitude (over the runway) with decision height (over the ground)? This mistake can be made by those who issued the approach plate, or by the crew.

In any event, they were overflying what looks like ditch with its bottom some 80m below the runway when the 100m call was made and the go around started. A little delay or "smoothness" in initiating the go around could have made the plane descend below that point more than it should have in a more vigorous go around. Combine that with a terrain that suddenly raises 80m just after that point and you have an accident.

I know there are things that don't add-up here.

To begin with, the DA/DH thing (descending a bit below it) should be possible ONLY in a precision approach. In a non-precision approach you never descend below the MDA, so you start to level off a bit above it. And confusing the altitude above the runway with the height above the terrain should also bo possible in a precision approach, since I've never seen a non-precision approach with the MDA stated as a radio-altitude (otherwise, in the part where you are supposed to fly that MDA, you would be copying the profile of the ground if you were to keep the radio-altitude constant).

But was there a precision approach after all?

And if there was one, that might explain the events as I told, but what the hell were they doing that low below the glide slope they were supposed to be following? They should have initiated a go around much earlier due to the unsterilized approach.

And if they were flying a non-precision approach, why on Earth were they using radio-altitudes (if they were, according to this story)?

I'm afraid I don't have the answer to this three questions, nor the slightest clue.

But I thought I'd share something that's been in my mind and that offers a different possibility to those that have been being discussed here.

[Peter Kesternich]

Gabriel - I am always amazed at the details in the work you do here. It's really great to have you contributing here

The major problem in the scenario you described, I believe, are the different sources. When it comes to aviation, I don't trust mainline journalism AT ALL. A regular journalist, who is not working for an aviation-related publication, has in all likelihood no better understanding of how aviation works than the general travelling public. This causes quite a lot of confusion, especially when it comes to terminology. Here's an example:

precision approach... Well - everybody in aviation knows what this means. But to a layperson it might simply mean that you have to work with a lot of precision to get a plane onto a runway, for example at night.

Therefore I am always very reluctant to accept any explanation that the general media put forward. Will be interesting to see what the official report about the accident in Smolensk says. I am pretty certain it will turn out to be a straight forward "busting minimums will kill you" accident.

[Evan]

I wonder if the press reports are confusing VNAV 'glidepath angle' with 'glideslope'.

There was some mention earlier in the thread that a military form of guidance exists there, but is not compatible with civilian aircraft. Since the Presidential plane is (at least in the U.S) a military asset, perhaps it was equipped with the ability to access this guidance. Or perhaps the conventional ILS can access the military system, but with inaccurate results. Or perhaps nothing of the sort exists there.

I also didn't see anything on the CVR transcript about guidance.

[Geebee]

Thanks for the summary and reflections, Gabriel.
The attached picture probably says the same in a visual way. This is what is posted on the Polish wiki page and which refers to DH rather than DA.
Anyhow, when I read and reread your personal interpretation, one can only conclude that a combination of human error and pressure seem to be the most plausible causes of the accident.


Meanwhile, the frustration and conspiracy theories in Poland are fueled by the delays in the hand over of the documentation, autopsy reports, court evidences, etc. Per se, I would not see that as more than an administrative delay. After all, we are dealing with a very bureaucratic country and an official investigation. However, this easily can be interpreted by many as a source for speculation. Let's give the Russian investigators the credit they deserve. For what it's worth, investigations in other countries would take equally long. Emotions are however very strong in this case for reasons explained by others already.

[Gabriel]

Thanks for the summary and reflections, Gabriel.
The attached picture probably says the same in a visual way. This is what is posted on the Polish wiki page and which refers to DH rather than DA.

That graph is wrong in some way or another.

There's a dotted line that says "RWY elev 255m AMSL", and that line is actually at the runway level.

It also says "DH 70m", and shows a segment between that dotted line and the glide slope. That means that either 70m is a DA, not a DH, or the segment should be drawn between the ground and the glide slope. It looks to me that 70m above the (depressed) ground would be too low, so my guess is that it's a DH of 70m. Unless of course the same mistake was made on the chart.

This graph also shows in a graphical way one of my questions: Regardless of the DA/DH issue, if there was a guide slope what on Earth where they doing so many dots below it at that point (the glide slope needle must have been fully pegged to the stop, or its electronic equivalent), and not initiated an earlier go-around due to the highly unstabilized approach.

[Evan]

This graph also shows in a graphical way one of my questions: Regardless of the DA/DH issue, if there was a guide slope what on Earth where they doing so many dots below it at that point (the glide slope needle must have been fully pegged to the stop, or its electronic equivalent), and not initiated an earlier go-around due to the highly unstabilized approach.

If the graph is accurate, the DA/DH confusion doesn't explain this. Is seems more likely that the glide path was started too early and then they intentionally proceeded below DH (due to latent or direct pressure). Is this possible that the DME equipment was inaccurate and a GP armed for VNAV approach was started too early? But shouldn't they be using GPS, or would a Russian military runway not be accurately placed in their GPS database?

I think one thing we can universally agree upon is that their positional awareness was compromised.

[Gabriel]

If the graph is accurate, the DA/DH confusion doesn't explain this.

It could explain part of it.

Imagine the plane being 70m above the "local" ground at the beginning of the ravine.

Is this possible that the DME equipment was inaccurate...

If there was a DME equipment...

[Gabriel]

I think one thing we can universally agree upon is that their positional awareness was compromised.

Do you mean that the did not intentionally fly into the ground?

Every CFIT is either suicide or loss of positional awareness.