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-   -   This confirms something! (https://www.pprune.org/australia-new-zealand-pacific/538419-confirms-something.html)

Wally Mk2 24th Apr 2014 15:14

Remember guys GT is preaching to the ill-informed (apart from himself)
Mr & Mrs Joe Public believe anything that's on a TV screen!


GT just like the authorities have no idea how why when or where this plane is! Everyone is now guessing & even the Media have dropped it from their headlines, it's stale news now, sad for the families though:-(


Wmk2

Sarcs 24th Apr 2014 23:00

MH370 Tripla sim stories with cred vs GT muppet show
 
From Avweb...:D

MH370 Sim Experiments

In Monday’s blog, I dissected the impact of the under-dressed sim instructor CNN used for its round-the-clock MH370 coverage, but what of the simulator itself? Like many, I assumed the simulator, which looked impressive on camera, was the sort of machine used to train and type rate pilots looking to find a 777 seat. Not quite. As described on its
web site, UFly’s B-777 sim is a highly detailed reproduction of the cockpit and systems, but since the 777 is fly-by-wire, how accurate does it replicate the real airplane’s control laws?

Maybe not so much. I mentioned that one of the interesting things CNN did toward the end of its intense coverage was to replicate what the airplane would do if both engines ran to fuel exhaustion. They even flew the airplane briefly on asymmetric thrust, since one engine would inevitably quit before the other. This was an attempt to illuminate what would happen if the airplane ran out of gas somewhere over the Indian Ocean, with pilots dead or incapacitated.

While Boeing has, understandably, tried to suppress speculation about the MH370 disappearance, sim operators—real, level D sims—all over the world have been experimenting with what-ifs in their multi-million dollar motion boxes. I’ve been corresponding via e-mail with a couple of 777 professionals, one of whom is a training captain for a major airline. This week, he sent me a summary of experiments done by one operator and reproduced by others. Bottom line: “You can throw any straight ahead flight path/impact calculations out the window.”

What this is, really, is not so much a test of the airplane, but of the software that runs it. No one was quite certain how the 777’s control laws would degrade and adjust to the loss of engine thrust and, briefly, electric power, with no human intervention. The results are eye opening.
The basic setup involved programming the sim with MH370s fuel, weight and CG conditions and letting it run out of fuel in track hold and altitude capture. Predictably, one engine flamed out before the other and a feature called TAC for thrust asymmetry compensation automatically applied rudder.

The speed decayed from 325 knots indicated to 245 knots. When the second engine failed, TAC returned the rudder trim to zero. Then the fun started. The autopilot dropped out and the flight controls reverted to direct mode. In the 777, Boeing designed three modes, normal, secondary and direct. Direct can be thought of as the modern equivalent of manual reversion; it gives the pilots direct control authority and strips away any envelope protection.

The sim experiment revealed that after autopilot drop out, the speed came back to 230 knots, but the nose slowly pitched down, eventually reaching 340 knots indicated and a descent rate of 7500 FPM. The bank angle got to 25 degrees.

At that point, the airplane’s ram air turbine, an emergency backup generator, automatically deployed and the copilot’s PFD came back, plus other displays. But the aircraft remained in direct control mode. The 777’s EICAS was peppered with alerts, including one that the APU had failed to start, which it would automatically do after the engine failure. But with no fuel, no APU start.

The airplane then essentially entered a stable, evidently non-damping phugoid with a maxium descent rate of 8000 feet and a pitch excursion range of 9 degrees down to 6 degree up and bank angles between 5 and 25 degrees. The speed fluctuated between 220 and 340 knots indicated.
The exercise was terminated at 10,000 feet, but there was no reason to believe the phugoid wouldn’t have continued until surface impact.

Although these findings are largely academic, I found them interesting nonetheless, especially the autopilot drop out. In the CNN sim clip, the airplane simply picked up a wings-level glide, suggesting to me that either the flight dynamics aren’t well modeled or they didn’t allow the experiment to continue long enough. Either way, it’s inconceivable that the impact would have been survivable, if indeed anyone was still alive to survive it.

Whether the type and violence of the impact would have had an effect on surface debris field distribution and thus probability of detection is similarly academic. One theory held that a survivable impact might leave the airplane largely intact and thus less or no surface debris. All we know for sure is that not a trace of the airplane has been found.

And that leads to this disturbing thought. My correspondent has mentioned to me a couple of times of having nightmares about what transpired in that cabin, never mind the cockpit. I’m quite certain he’s not alone and I’m equally certain your imagination is vivid enough to construct a palette of scenarios, so I won’t catalog my own. There’s not much comfort in knowing that we can at least ponder how the airplane might have behaved, but at the moment, with precious little else known, it’s at least something.

Wednesday a.m. addition: CNN shot
this background video that offers more information on the simulator.

Which kind of matches the Phearless Phelan article..:ok: :A Boeing 777′s last descent

*Lancer* 24th Apr 2014 23:27

The 'simulator's' AP remained engaged after loss of the second engine... not a very good recreation. :ugh:

RampDog 25th Apr 2014 11:35

http://oi58.tinypic.com/2hf4175.jpg

This is the image from the article Annulus Filler was referring to earlier. GT aka Biggles getting his comeuppance!!

Blueskymine 25th Apr 2014 12:24

Also funny in the Australian aviation magazine is the commentary from "a pilots view". It's taking the piss out of the expert in his own magazine.

Worth coughing up a tenner, even if the expert does have a couple of poorly written articles in the said magazine.

I think the experts opening paragraph about mh370 is absolute gold. Particularly this quote. "Lessons are being learnt". I don't know about you, but we don't even know what happened yet. Maybe the expert is learning a few things. He knows how to turn and push the heading selector and that he can only select 43 on the MCP. (You can disconnect the autopilot and go higher you know). He knows how to put the flight deck door to lock down. He also knows how to deselect acars. His biggest lesson though is he's out of his depth in a toy 777 sim and comes across as confused, aggressive and like a rubber neck trying to make a name for himself off the back of a tragedy.


GT's only aviation industry experience is as a baggage handler for MMA in Port Hedland.
What's the difference between Geoffrey Thomas and a duck?

A duck can fly!

SOPS 25th Apr 2014 12:38

And in a real 777, at least the one I fly, the door switch won't stay in the deny position. It spring loads back to the centre position. You have to deny ech individual request. GT is a turkey of the first order.

Oh, and you can't deselect the ACARS like he did, at least not with our installed software.

Chocks Away 25th Apr 2014 13:14

That's what I was saying earlier SOPS, time for them to upgrade their SIM software package me thinks because it certainly doesn't act like the Honeywell AIMS/Fly-by-wire package on the real Tripla!

Blueskymine 28th Apr 2014 07:22

I can't believe this headline seeker is at it again.

He wrote in his newspaper the hijack code in his tabloid article on the VA Bali flight.

I think someone needs to get in touch with the editor of the west Australian and pull this writer into line.

Yes you can find out what it is if you delve into airway manuals available online, but the average deadbeat wouldn't know where to look. We can't make it too easy for them.

I'm disgusted.

Australopithecus 28th Apr 2014 07:35

Well, what do you expect? G.T. came to some small fame courtesy of the lazy Australian journalist who does not look past the ruthless self-promoters for colour background commentary. Thomas has cashed in with a kind of almost-informed-commentary-for-cash-or-kind that has allegedly yielded Chairman's Club membership, travel benefits and some notoriety.

It is up to us as an aviation community to vocally and aggressively show his ruminations to be the tripe that they are. Every time he rears his (profoundly boof) head, a well-spoken pilot should offer a counterpoint to each of his arguments.

Hell, a simple challenge to him to disclose any and all QF supplied reward would be enough to render his testimony suspect. Nothing would give me greater pleasure to see Livy's creature thus exposed to the wide ridicule that he so richly deserves.

m-dot 28th Apr 2014 08:08

Sunrise journalism at it's best!

Be interesting to see what Boeing have to say to him. Buzz on the flight deck is that it's been sent to them.

Pinky the pilot 28th Apr 2014 11:19


Be interesting to see what Boeing have to say to him
''You will be hearing from our Lawyers" perhaps?


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