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RetiredF4:Sorry to say that, but the thread is again drifting from facts to speculation and assumption.
All Quotes janeczku
Eh eh, i dont think so! Considering all hard facts, the scud dive theory is based on strong evidence and not speculations:
1. It has been officially confirmed (by PAF investigation) that Jak-40 busted their minimas going below 100m and conducted landing too high above the treshold. Given the absence of technical failures and glidepath guidance by NDB and ATC, this is evidence "e contrario" that they were conducting a "scud" or "rat dive".
If you would know, how to fly an aircraft with deliberate thought below the minimum to the threshold and land out of it, you would also know, that you are then not ending up high at the runway threshold, because you already descended low before the missed approach point and therefore approach the threshold low already.
Being high over the threshold comes from flying towards the threshold after passing the point where the decision height intersects the glidepath, without further descent, therfore ending up high on glidepath. The time when you pickup the lighting system (in this case the beacons left and right of the threshold, which had been explicitely mentioned by the Yak-Crew), the descent ends in a long touchdown.
2. The Jak-40 pilot informs the TU-154, that there is a cloud base "well below 50 meters", but in the same breath tells them they should try by all means to land. Thus he suggested an approach that would violate the airport, planes and pilots minimas. This is evidence for the kind of "esprit de corps" that prevailed in the PAF special regiment. - eg giving a damn about "cumbersome" rules.
The YAK does not use the words "by all means", that is your wording here. YAK crew gives a site report, an own expierience, which has actually no official value. If the weather would have been reported better than the official weather, it would have had again no official value either. The only legal weather is from the met-office. The approach itself can not violate minimas, only the pilot can do it by continuing the approach to beyond the published minima without runway reference (for example approach lights).
3. Tu-154 were well aware of the limited visibility and the cloud base, that would in no way allow them to get visual at MDA. Nevertheless, 20 seconds after receiving this information from Jak-40, they decided to try an approach.
Again, to commence the approach down to the minimum is no violation of regs and rules. It is not legal however to continue such un approach beyond the published minimums without field environment in sight.
This decision would only make sense if they intended to bust minimas trying to establish visual below the MDA.
There are a lot of reasons to do so, beginning from the practice to gain for the aircrew, to the good will show for the president, to the final objective to land out of it, if the field is in sight.
It is hardly believable that they expected to have even a slightly change to get visual at MDA with a cloud base "well below 50m" and "visibility of 200m".
What do you know from flying such an approach, from developing weather to good or worse? Fog comes and fog goes, in local areas sometimes within minutes. might be thick like in london or it might be thin and patchy. If you are already there and wish to land, why not give it a try? Performed correctly and not lower than allowed minimum it is safe.
To assume, that every crew, who starts such an approach is a insane minimum buster is far feetched.
4. It is proven by the FDR and CVR recordings that they didnt call for or conducted a go-around at 120 or even 100m, neither did they get visual ("Voice in cockpit: You can't see a thing"). Instead they kept descending below MDA.
We have elaborated over this long time ago. Using R-altitude instead of B-altitude, wrong setup of Pics B-altimeter, target fixation outside, the behavior of ATC with "on glidepath all the time until 25 meters above threshold (where first warning "horizon" happened...... i repeat myself, but those are facts out of the MAC report and no speculations.
5. They used radar alt from 300m, which was their SOP on Jak-40 in a landing configuration. If they had have had the intention to do an approach by the book, means descending to MDA and then decide on landing they would in now way have used the radar alt. Given the decision to bust minimas, it seems logical for them to use the radar alt, because of - ironically - better ground level seperation indication in a hilly terrain.
If you wouuld ever have done a contour flying with radar altimeter even in a agile aircraft and not in a plump hen like the TU154 you would know, that it would exactly be vice versa. The radar altimeter is the least exact instrument in hilly terrain, it jumps and it lags and it shows only altitude reference, which is already history (because it is just passing below you)
You set in the correct ressure on all available barometric instruments and crosscheck them against each other. Then you would take the lowest indicating as reference and adjust the others accordingly. Now you are on the safe side.
So your assumption is not logical, it is nonsense.
6. The last message from Jak-40 ("Visibility now 200") shortly before final didnt lead to any reaction in the cockpit. They knew that with this visibilty, there is no chance of getting visual at MDA. Nevertheless they continued to final approach, which is evidence that they had plans to do their approach the polish way, busting the MDA (Poles are both known for and proud of their ability to "kombinowac", which means to wangle sth not by the book under difficult circumstances).
see my point of view from sstatements above. You are assuming again......
7. FDR shows, that as of the height of 80 meters pull force was applied to the control column two times within 4 seconds, leading to counter push of the still engaged autopilot, because the force was not enough to override it. It is not known if that was done by the PIC or the FO. There are two possible explanations for this:
a) An attempt of the FO to conduct a go-around. Highly unprobable, as go-around thrust was not applied and autopilot not disconnected!
Wrong asumption again. CVR states exactly, that they agreed to do the go around in automatic mode with the go around button. That one however was not active due to no glidepath guidance, therefore it would not disengage the autopilot and it would not advance the throttles. It also shows, that the crew had no intention to manually disengage the autopilot and to manually increase the thrust, it was intended to let the automatics do the work.
If you allow me a speculationh here (which i´m very reluctant, but i might be entiteled to one assumption also), it might show the attempt to go around with the button, as it is located on the steering horn. Speculating further, one attempt by the pilot, the other one from the FO. And it could not show on the FDR, because the FDR only records the activation of the mode, but not the pressing of the inactive button.
b) An attempt of the PIC to level out the A/C at an (still safe) altitude of around 50m trying to get visual in horizontal flight. When, 3 seconds after the first pull of the control column, the autopilot pushed back and plane didnt level out, the PIC realized something went wrong and initiated go-around, disconnecting AP and applying go-around thrust.
Did you really read the MAK report? The autopilot was never disconnected manually. The pilot pulled with more than 15 Kg of force on the steering column and did a force disconnect on the autopilot simultaneously applying full power. That was a panic reaction and no deliberate act. MAK even states correctly, that this was not the normal method to disconect the automatics by the appropriate buttons.
Quite probable! And also proove that they were actually still aware how to do a go around on this plane!
It proves, that nobody in the aircraft cockpit was aware at all about their situation until it was too late.
Whatever hard facts and evidence you see, the conclusion out of them is nothing but speculation.
Fact being, they did a lot of mistakes from beginning to end, and those had been enough already to lead to the outcome. You dont need any intention for a scud run or for busting a minimum to crash that aircraft with such a "green" crew when doing such a bunch of mistakes.
The agenda of the scud run may serve the political intentions, but these political aspects have no weight in the occurance of the accident.
franzl