Polish Government Tu154M crash

[Alice025]

Well, Vasily Ershov wrote the Polish kommander is talanted. (text-book author on TU154 piloting)
But also that piloting book - incl. minima - are not there just? as words but were "written by blood".

[criss]

You are not worth talking to.

So give us a break and run away.

[Falcone]

Alice,

In 21 century we should not relay on rules written in blood. In modern aviation today we relay on rules, procedures, CRM, discipline, proffesionalisam, knowledge and else.

False proudness and sentiments are for amateurs.

[Ptkay]

It is about PPRuNe. It is about learning from mistakes, own or mistakes committed by others.

Yes, you are absolutely right.

But to achieve this goal we have to know, first of all,
what kind of mistake the pilot made,
and then, what was the reason, he made such mistake.

So the first mistake, as you properly stated, and we know for sure,
was flying below minima.
Why he did it? I think, IMHO, the pressure, direct or indirect was the reason.

The second mistake, already in approach, he was flying wrong glide path.
Why did he do it? At the moment we can only speculate.
Taking into consideration, that, for political reasons, the true reason
might be never revealed, we are left with our "educated guesses"
or, if you prefer to call it this way, useless speculations.

Whatever the name, the educational value is undisputed,
at least IMHO.

[criss]

So the first mistake, as you properly stated, and we know for sure,
was flying below minima.

Nope. The first mistake was commencing the approach.

[Ptkay]

Falcone, take it easy.

In modern aviation today we relay on rules, procedures, CRM, discipline, proffesionalisam, knowledge and else.

"WRITTEN IN BLOOD", means based on tragic experiences of the past.

The "rules, procedures, CRM, discipline, professionalism, knowledge"
come from experience, also bad experience like accidents.

They were not given to us like the 10 Commandments by God the Almighty
curved in stone.

They change with every accident that happens, also in spite of them.

BTW: I hope by "proffesionalisam" you mean "professionalism"...

[Ptkay]

Nope. The first mistake was commencing the approach.

You are absolutely right. (As usual)

My mistake. (...not the first one...)

[Falcone]

PTKAY

I undersign your post.

We can learn from mistakes only if we try to identify same. For more then 25 years in air investigating commities I have never seen fully disclosed reasons for crash. Ever!!!

In this case wrong glide path is obvious, what is less obvious is what has delayed go-around? If any has been executed.

I say if any, becuase a lot of preliminary facts are pointing to no go-around or at least not fully commited go-around was executed.

I hope one day we will found out thruth.

[Falcone]

Commencing approach alone is not mistake. But if one continue approach behind certain point (OM/4NM/1000ft) is mistake.

Descending below minima is definitely mistake.

Sorry for misprint. English is not mine native tongue and keyboard does not help. It is bit old.

[criss]

If one commences the approach when wx is so much below minima, for me it's a mistake which possibly shows the mindset of get-there-itis.

Falcone, but that's exactly the point you either don't get, or there is some misunderstanding. That they were too low is an obvious fact. But what we don't know is why they were so low, and were they aware of that fact. You seemingly already apportioned the blame and the case seems easy for you - they were too low, and surely altimeters showed it, so it's a pilot error. Yet, there are dozens of possibilities here - wrong wx information from tower, wrong setting in the cockpit, instruments failure, human error (wrong readout), wrong charts (as we know, aerodrome info wasn't really high standard), going deliberately below minima, and many more. That's the whole point of investigation, and also our discussion here.

[cats_five]

Originally Posted by Falcone

If one execute go-around at published minima can not end up being to late.

Published minima are calculated to take in account the worst performing aircraft for certain approach category of A/C.

If he doesn't know he's too low how is he going to know he needs to do a go-around?

[captplaystation]

It has been mentioned that their first "hit" was below the level of the runway threshold.
Even if they decided to push their luck and descend a little below minima (say 200' rather than 300' QFE) this would not result in what happened.

Either these guys have knowingly descended to ,at or even below, the level of the runway without the required visual reference (or they "thought" they saw the R/W lights ) . . which seems insane in its criminal ineptitude, and therefore scarcely believable to any professional pilot OR. . . . . . they didn't realise how near the ground they were, which means no-one was looking at the altimeter (again scarcely believable)
OR . . it was incorrectly set.

Even if they set the wrong (too low) minima, or decided to bust them "a bit" they wouldn't manage to hit the ground BELOW the height of the R/W without some other mistake.

[SLFinAZ]

I'm pretty sure i've read the entire thread and I have one question that i'm unaware of a clear answer to. I know that ATC "suggested" they head to an alternate destination. I know that the pilots elected to a landing attempt with the understanding (or so ATC thought) they would abort if conditions were unsuitable. I do not recall any clear indication that the approach was flown as a "PAR" approach....so did ATC call out the glide slope errors?

My understanding is that any plane not stable on the glide slope at a certain point is normally going to abort simply based on that instability regardless of other factors.

If in fact ATC did call out the error I can't fathom how/why TOGA wasn't immediate once the instability in reference to glide slope was recognized??

[MartinS]

Amen to that, captplayistation. To find anything more, we need more information, hopefully released on Thursday.

[mirogster]

@ SLFinAZ
I'm pretty sure that pilots 'knew' that airfield and specific procedures of Russian ATC (military/non military/civil).
They were there few days earlier.
And if I'm not mistaken, that a/c also was there not for the first time.

[SLFinAZ]

Not a question of how familiar they were with the airport, just a question about the non stabilized approach. If they were under the glide slope isn't the approach considered unstable?

they are way under the glide slope (looking at chart in post #803) well before they were in danger. Did ATC call out the deviation and if so was it then obviously ignored? These guys got way out of whack long before they got whacked by tree's....

[Uphill]

how it could be

these posts are from Sergey Amielin blog made by Tom tu154 pilot
"Considering horizontal visibility 400m if they had under the plain flat terrain
crew would start to see anything in front of them after being at height approx 40m above
terrain.At approach speed 70m/s which was correctly astimated with acuracy -2/+8 ms
plane flied in best case after 6 s at place which crew managed in best case see
6s earlier."
"on tu-154 taking into account time needed for turbine to reach starting power and
plain inertia at mass about 65 ton especially at ascendnig terrain 6s
is a bit to little time to go from normal height decresing to incresing and not touching
the ascending terrain"
"not considering wrong setup of MDA/MDH or wrong given/set QNH/QFE crew probably
decided to use RA in order to get at 40-50 m AGL about 1 km before threshold
only from this hight they had a chance to land at visibility 400m whicch above
forest before runway could be even worse. For some reasons they did not control
barometric altimeter and did not notice they got 10m under threshold of the runnway
(255 m above see level)"
"they had a chance to succceed if not the deep ravine seen on google earth.
Observing that they are constantly high (according to RA because of ravine)
they increased lowering speed, later they saw in the end terrain going up
in front of them, being at about 40-50 m above ground, initiated dramatic go-around,
but it was to late"
"it's possible they could support themself with FMS, using its simplest functions
(unfortunately not VNAV) and manually set threshold coordinates and landing course.
As well to estimate distance to threshold. Unfortunately a lot points it was
not set correctly or if at all."
"it's bad this airport was not measured with WGS084 (PZ-90). If it was
and was placed in AIP it would be also in database EGPWS and FMS. Corrrect use
of FMS especially its advanced functions could prevant tragedy.Our reconesance
would be usefull when airport was used many times, including bad weather.
Airport mesurement and obstacles as well"
"but MDH 120 m rather would not change. and what goes with it visibility condition
1000-2400 m would remain. Approach lower is a break of basic safety rules.
Does not matter with EGPWS or FMS or without them"
"i would like to be wrong but i am afraid that CVR recorded "turn off EGPWS,
to not scream airport not found in database" or "we ignore EGPWS - this aiport
is not in database". We will hear also "we approach according to RA so
that at 1 km before threshold/passing BLR we will be at 30/40/50 m. Otherwise
with this visibility we can not make it, and we can not not to try"
"Anybody knows if Outer NDB located 4 km from the threshold exists? I can't located in Google
Earth, while the Inner NDB can be located 1 km from the THR in Google Earth"
"as i wrote before, terrain in front of him he would be able to see
being at apprx. 40 m above ground (but when terrain is flat, when it goes up/down
it could be a little more or less). It would be good if Siergiej could make this
picture to the right about 500 m apposite approach direction. This would allow
to estimate the moment he noticed the terrain"
"Сергей, could you please be so kind and extend the picture about 500 m to the right, in the
direction opposite to the approach direction, so an analysis can be made when the crew was able
to see the terrain, considering 400 m visibility. They had to be approx. max. 40 m above ground
level, maybe lower, when they saw the terrain and trees in front of them."
"Сергей, are you aware of existance of Outer NDB, located usually 4 km from the runway
threshold? I can't find anything which looks like NDB facility anywhere on extended runway
centerline, except for Inner NDB, 1 km from the threshold. using Google Earth"
"Continuing, with terrain going up and visibility 400m crew could notice terrain if front of
them later at a bit lower height apprx. 30 m above ground. On the other hand with
terrain going down crew could see terrain if front of them at a bit higher height
appox 50 m above ground. Analizing earlier profile i conclude that crew noticed terrain
being approximately above ravine bottom, or rather 100 m after it. being at height
apprx. 260 m over see leverl (5 m over threshold level)"
"Peter, as i said earlier it is possible crew did not notice in previous flights
slightly hilly terrain on approach and deciding sickly to land even if it meant
break the rules and common sense, concentrated on reading radioaltimeter.
turning off in the end scanning barrometer altimeters. Knowing that
in these visibility conditions they will see ground at approx 10 seconds
before touchdown. Everything happens than very quickly."
"Becouse ravine bottom goes about 50 m below runway threshold, they increaced
lowering speed thinking they are to high. They saw terrain going up being
a few meters about threshold level. But lowering at 6-7 m/s, weighing ap. 60-70
ton Tu 154 configured to landing can not be forced to ascend in a second.
You loose next 15-20m and fly in this time ap 350-400 m before
transisioning to ascending - in first seconds free"
"it takes a few second before plain reaches his max accending speed
in landing configuration. At the same time it is only after reaching
positive ascending that the chasis is hiding and position of
flaps to starting position decreases eg from 40 to 20 degrees.
This takes anogther few several seconds. I think crew using radio altimeter
wanted to approach to aprox. 50-60 m above ground and only than
do eventually go-around. It was not reasonable."
"additionally they forgot about ravine which bottom was about 1300 m from threshold
If it was not there if terrain was flat as they assumed they would manage to land.
but it seems to me that with 400 m visibility and approach speed
apprx. 135 knots (70m/s) little probable. or they would do succesful go-around.
Landing with ILS cat I approached to 60 m abouve ground,
and with cat II even to 30 m legally. Tu 154 has autopilot with function
autoland but you need ILS for that. It was not there."
"i think if they did not see terrain using radioatimeter about 2 seconds
later they would start go around. They were not suiciders only they
had to high selfesteem. How do i know? Because i have a few landing like that
behind me. and it also seemed to me that published minimas are for loosers
and not "ases" like me. Only i had a little more luck and stayed alive to point when
i was able to kick these ideas out of my head"
"aha plane found itself at lowest point 10m aprox. 245 m abouve see level)
under threshold runway level and not several dozen meters."
"Сергей, спасибо. It means probably only 1 or 2 NDBs and approach monitoring radar. No PAR. The
question is only: 1 or 2 NDBs?"

[timraper]

didn't really matter a jot how well they knew the airfield or whether 'the aircraft had been there before'. Looking out the window at fog

[Tarq57]

SLFinAZ,
We don't actually know yet that they were on a type of approach that actually had a glideslope. They may have been on an NDB or twin NDB approach - for which the minima is typically around 3-500ft AGL, depending on terrain etc - or the Russian equivalent of a PAR or GCA approach - the radar-based "talkdown." (A PAR does have a glidelsope; the pilot follows it by reference to controller instructions. It is not displayed in the flight deck.)

If they were on a PAR approach, for example, and it was calibrated and working correctly, the controller would have been telling them for quite some time prior to the collision to climb.

If they were on a twin NDB approach..well, I would hope there would be no pilot in the world who would deliberately go so far below the published minima on purpose "for a look", as indicated above by captplaystation. Maybe sneak a hundred feet lower, but not 4 or 5 hundred.

Another possibility was that they were in clear air above the fog bank and attempted to visually navigate to the runway, underneath it. That sort of approach is generally unsafe, considered bad airmanship, and illegal (usually) even in a light, slow, nimble aircraft like, say, a 172. It would be highly unlikely anyone would attempt it, regardless of outside or internal pressure, in anything at all, and especially not a jet airliner. There's no future in attempting to navigate visually, at low level, when the visibility is 500M. Or even 1000M.

There are indications that there were communication difficulties between the crew and the controller/s. Especially in (readbacks?) of numbers. There was a suggestion in a television broadcast from a senior ranking Russian officer that the controller had been telling the pilot to "level out" at some stage during the approach.

I would be very interested to know what altimeter setting the crew used, whether it was QNH or QFE based, and whether the crew knew which it was; the approach in use, the charts used for that approach - and especially what reference was used for altitudes or heights on those charts; any cross-checking of height against the radio altimeter, and any discussions on the landing minima and missed approach procedure.

I believe that it's likely the crux of the reason for descent below the minimum will be associated with these factors. It seems likely the crew did not realize there was anything wrong until (possibly) they actually hit the trees or maybe a second or two prior. I would not be at all surprised if a QNH reference was selected on the altimeter sub-scale, but the crew inadvertently flew the approach using QFE reference. Or (very simply) the wrong QFE reference was set, due to language differences. It would have to be about 15- 20 Hpa out. Maybe more. (The difference between QFE and QNH for this aerodrome is approx 29Hpa.)

I would imagine the reason the approach was commenced in the first place under the circumstances would be to satisfy themselves and (especially) their passengers that at least they'd had a look, expecting it to be unsuccessful. Some would consider that a reasonable course of action provided the approach and missed approach was briefed for and the correct altitudes displayed and used.

All this talk about cutting down trees on the approach, or a NDB/beacon at a possibly non-standard distance from the aerodrome, or what blind-landing aids were or were not fitted, is red herrings, I'm afraid.

[ECAM_Actions]

Falcone

I ask why they descend below minima and did not cary immidate go-around action. Regardless of postion at 1km before RWY or at 5km after same.

If you take the fact the outer marker was at 6 km and not 4 km, and that they had somehow ended up working on 4 km, one conclusion I can draw is that they thought they must be over the runway, and given the pressure of needing to land, descended to get the lights/runway.

The only other plausible cause I could see is the terrain under them; did the navigator check RADIO ALTITUDE, and see it was OK/increasing, before they flew over the up-going side of the hills, or was everyone looking out the window trying to acquire the runway?

The rest as they say, is history.

The Russians have a system whereby if the Captain is flying, then no-one monitors him. The F/O handles the radios, the navigator navigates, but for some reason it appears even he failed to notice the outer marker was further way, and that they were subsequently too low.

Tarq57

We don't actually know yet that they were on a type of approach that actually had a glideslope. They may have been on an NDB or twin NDB approach - for which the minima is typically around 3-500ft AGL, depending on terrain etc - or the Russian equivalent of a PAR or GCA approach - the radar-based "talkdown." (A PAR does have a glidelsope; the pilot follows it by reference to controller instructions. It is not displayed in the flight deck.)

From all the information available, it would be a dual NDB approach. There isn't an operational RADAR at the facility, so this was not even an option.

ECAM Actions.