Atlas Air 767 down/Texas

[lpvapproach]

Originally Posted by FIRESYSOK

The accident site seems to be near the RDFSH waypoint which would be flown to in the event of runway 27 transition,

I am looking at the linkk1 star. What is the "runway 27 transition" - there is no such literally named transition on the plate. I also heard this mentioned listening to the ATC, I have not heard this previously but dont fly in the area. Thank you.

[wiggy]

Originally Posted by lpvapproach

I am looking at the linkk1 star. What is the "runway 27 transition" - there is no such literally named transition on the plate. I also heard this mentioned listening to the ATC, .

It’s the transition from the terminating waypoint of the STAR onto the published approach - take a look at the 27 ILS plate, you should find it there.

[fdr]

Originally Posted by tdracer

I wouldn't consider 100m x 200m large at all - in fact for an aircraft the size of a 767 that's on the small side. It would also rule out any in-flight breakup (unless of course they find bits at another location).
I also would consider an uncontained engine failure to be rather unlikely since they'd have been at a relatively low engine power setting - most engine breakups at takeoff power sets, or at high altitudes where the physical rotor speeds tend to high. I suppose a major bird strike might cause enough damage and a large enough imbalance that perhaps the engine could start coming apart, but again the probability would be low at relatively low rotor speeds.
But, one of more big birds through the forward bulkhead that took out some flight controls (remember, the 767 is basically a cable controlled aircraft)? Even if it didn't incapacitate the crew they'd have precious little time to react...

The debris field of the airframe is commented on, and is not particularly large as reported so far, but the point of interest will be any debris in the 3-4nm to the east of the aircrafts impact point. At idle, the engine still has around 20-25% of the kinetic energy of the full thrust uncontained failure case, enough to cause further damage. As far as I recall, there has only been one incident on the 767 GE where an uncontained failure damaged the second engine, and that was a liberated disk fragment bouncing off the ground and impacting the other engine.

[PuraVidaTransport]

For those of you who are talking about diversion fuel and don't have a good idea of airports in Texas, just an FYI post. There are a LOT alternates (runway length ~8000ft or longer) as close or closer than DFW. Three in Houston (Bush, Hobby and Ellington Field (NASA/military)), four airports in the DFW area (DFW, Love Field, Alliance and the Naval Air station in Ft Worth), San Antonio, Austin, Waco, New Orleans (La), Tyler, Longview, Shreveport (La), Corpus Christi, Victoria, and Laredo plus a LOT of others with shorter runways they could use in an emergency like the two in Conroe, College Station airport (Easterwood), Army airbase at Killeen, Stinson Municipal in San Antonio, Austin Executive, Beaumont, Baton Rouge (La) and Lufkin. This is also not a complete list just ones off the top of my head.

[CONSO]

Originally Posted by tdracer

Those pieces do not look to me like parts of the engine nacelle - the honeycomb is too thick. Best guess is a moveable aerodynamic surface (e.g. flaps or part of the tail)

Looks to me more like NON structural fairing or possibly interior panel which used a light blue adhesive - perhaps a cargo liner ? nearest top edge of grey painted ( aluminum ?) in photo is not torn but simply folded over some semi circular object eg a manufactured ' cutout '

[thabo]

Originally Posted by JPJP

Those photos are very interesting. The gentleman on the left is a GE Rep, but I don’t know if that indicates they we’re looking at a piece of engine or cowling. The damage to the material is quite idiosyncratic.

Where’s an engineer when you finally need one ? David R ?

Looks like a part of the 9G rigid barrier at the front of the cargo deck
can't think of any other item off-hand which is made from aluminium honeycomb and is that thick

[Air Profit]

Not speculating on cause, more a question: would it be possible for a sudden negative-g load to break free a cargo pallet and force it upwards into elevator control cables (assuming that is where the cables are located on a 767)?

[CargoMatatu]

This brings back memories from my earlier days in my aviation career, remembering the Dan-Air 707 crash on approach to Lusaka in 1977 where the starboard horizontal stabiliser detached on approach.
Lost some good friends and colleagues in that one, and in more recent times I am ex Atlas!

Not suggesting there is any link here, just an unpleasant similarity.

R.I.P. brothers.

[Homebrew1]

Originally Posted by Air Profit

Not speculating on cause, more a question: would it be possible for a sudden negative-g load to break free a cargo pallet and force it upwards into elevator control cables (assuming that is where the cables are located on a 767)?

Wouldn't have though so. Would need to be significant and in that case would also be exceeding A/C structural limitations.

[B2N2]

Originally Posted by Agent1966

I heard it....very faint.

1. I don’t hear anything on that tape
2. Any perceived noises or sounds out of context don’t mean anything.
Even if “pull” was said and picked up by any of the microphones it could be dozens of things.
A comment about seat adjustment, seat belts, folding table tops, crew bags, door handles anything.

”Hey could you grab me the sunshade?”
”Go ahead just pull”

Not trying to be facetious but if you’re trying to hear “Pull” then consider the Youtube videos of cats sounding like they say hello.

[Zeffy]

NTSB Briefing - 24 Feb 2019

NTSB briefing by Chairman Sumwalt:

You Tube

[Carbon Bootprint]

The crew members have been identified in today's Houston Chronicle. According to the paper, one was a Mesa captain and new father who was jumpseating to Houston to begin his "dream job" with United Airlines this week.

Very tragic all around.

[Mike Park]

Thanks Tim Vasquez, very good information.
Mike, 30,000 hrs B-737

[lomapaseo]

Assuming it's factual doesn't, a steep dive into the ground with a tight debris pattern have to fit an aerodynamic principle of flight ?

[derjodel]

So Fly Dubai, Lion Air and now Atlas all share:
- Boeing airplane
- Nosedive

Lion Air is probably an outlier, but then again, what if all 3 have trim management in common? Because at least Lion and FlyDubai do.

In Addition Fly Dubai and Atlas both share low visibility and approach/final, right? And somebody mentioned constant speed. It seems Atlas air was actually slowing down and FlyDubai was just slightly accelerating, both despite nose down, if FR data is to be trusted (can't post links, sorry).

Seems like some kind of a pattern, doesn't it?

[SeenItAll]

Originally Posted by derjodel

So Fly Dubai, Lion Air and now Atlas all share:
- Boeing airplane
- Nosedive

Lion Air is probably an outlier, but then again, what if all 3 have trim management in common? Because at least Lion and FlyDubai do.

In Addition Fly Dubai and Atlas both share low visibility and approach/final, right? And somebody mentioned constant speed. It seems Atlas air was actually slowing down and FlyDubai was just slightly accelerating, both despite nose down, if FR data is to be trusted (can't post links, sorry).

Seems like some kind of a pattern, doesn't it?

Not at all. Statistics is about accepting or rejecting hypotheses that are made in advance of knowing the data. Claimed confirmation of a hypothesis that was generated after seeing the data is just cherry-picking. Given there are so many parameters to cherry-pick from, it is sure that you can find some that will all align between the incidents -- but this has no probative value as statistical inference. Indeed, each of these crashes is so different from one another in terms of the stage of flight, that I doubt any similarity will be found. And note that trim problems generally don't cause an immediate nosedive into the ground. You generally see the flight crew struggling with the imbalances for some minutes (or at least multiple seconds) before control is finally lost. That doesn't seem to be the case with the altitude profile shown here.

[EDML]

Originally Posted by derjodel

So Fly Dubai, Lion Air and now Atlas all share:
- Boeing airplane
- Nosedive

Lion Air is probably an outlier, but then again, what if all 3 have trim management in common? Because at least Lion and FlyDubai do.

In Addition Fly Dubai and Atlas both share low visibility and approach/final, right? And somebody mentioned constant speed. It seems Atlas air was actually slowing down and FlyDubai was just slightly accelerating, both despite nose down, if FR data is to be trusted (can't post links, sorry).

Seems like some kind of a pattern, doesn't it?

It is physically impossible to do a steep dive in a big jet without accelerating. Even with the power pulled back to flight idle the plane will accelerate very quickly in a steep dive. The kinetic and especially location energy is simply too high compared to the aerodynamic drag of a jet. That is a different story in propeller driven aircraft where the propellers add a lot of drag at low power settings.

[physicus]

It looks like the airplane followed a parabola, maintaining forward velocity while building up vertical velocity, as evidenced by the near constant GPS (=ground) speed in the FR24 data. As Sumwalt stated in the briefing, the aircraft flew wings level but in a steep nose down attitude. Lack of elevator effectiveness springs to mind. In the presumed absence of intent (i.e. suicide) it remains to be seen whether that's a runaway trim, complete loss of elevator control, or loss of elevator/tail surfaces. In level flight, the tail surface provides a net down force, lose some of that surface, and an up moment of the tail ensues resulting in a nose down moment on the pitch axis.

[derjodel]

I know, and indeed LionAir FDR data indicates acceleration. For the other two there's only ADS-B data available at the moment I believe? FlyDubai did accelerate in the last moments, but only from about 180-230 while it was in steep dive.

[derjodel]

Originally Posted by SeenItAll

Not at all. Statistics is about accepting or rejecting hypotheses that are made in advance of knowing the data. Claimed confirmation of a hypothesis that was generated after seeing the data is just cherry-picking. Given there are so many parameters to cherry-pick from, it is sure that you can find some that will all align between the incidents -- but this has no probative value as statistical inference. Indeed, each of these crashes is so different from one another in terms of the stage of flight, that I doubt any similarity will be found. And note that trim problems generally don't cause an immediate nosedive into the ground. You generally see the flight crew struggling with the imbalances for some minutes (or at least multiple seconds) before control is finally lost. That doesn't seem to be the case with the altitude profile shown here.

Not at all. Indeed the p value (if one is to use the dreaded p value in order to accept hypothesis) should be adjusted and fairly small. In essence, we could go in blind over all data available, but adjust the p value according to degrees of freedom available to avoid false positives.

Now given that the flight data sample is huge (say, all flights in the past 3 years), the probability of false positive is actually small anyway. So is there a statistically significant difference between # of flights that did/didn't crash in the group of flights which are Boeing in low visibility on final/approach?

And btw, picking a hypothesis up front makes no difference. Imagine 20 different statisticians would decide to test a hypothesis over flight data, each unbeknown and independent of each other. Each would choose a different parameter, but p of only 0.05. Those results would not be different, but there would indeed likely be at least 1 false positive due to stupidly large p value (0.05 is really astronomical when you think about it).