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-   -   EVA B777 close call departing LAX (https://www.pprune.org/rumours-news/588540-eva-b777-close-call-departing-lax.html)

Hotel Tango 24th Dec 2016 18:28


I'm trying to think if I've ever had a heading like 018 (other than maintain runway heading) given for vectors in airline flying. If that's what I thought we heard, like everyone here says, I would question and confirm.
I totally agree that a radar vector to 018 just wouldn't happen. However, we just don't know what they were thinking. There may even have been a difference of opinion being "discussed" on the F/D, with the captain insisting on his interpretation.

Denti 24th Dec 2016 19:04


All Boeing products afaik turn in the direction closest to the HDG target in AP HDG mode
Thats a behaviour i have only seen in very old 737 classics. Even in newer classics and all NGs i have flown the AP/FD followed the direction one turned the bug, happily for a 360 degree turn. However, if one selects the bug first while in another lateral mode and then presses the HDG button the AP turns the shortest way.

That might however be a pin programmable thing.

ZOA ATC 25th Dec 2016 05:42

ATC are required to check readbacks
 
:ouch: [QUOTE=Right Way Up;9615850]US ATC are not obligated to check readbacks and challenge.


ATC is definitely required to listen to and correct readbacks. If we for example issue a descent to FL 330 and it is acknowledged with a readback of "descend and maintain FL 230" we are now responsible to the same extent as if we had issued the descent to FL 230. On rare occasions I have seen the FAA try to also fault the flight crew, but without fail if a loss of separation of any sort occurs we will be considered at fault.

ZOA ATC 25th Dec 2016 06:01

Did ATC say turn left
 
[QUOTE=Hotel Tango;9615777]We don't actually hear her turn instructions (did she say left or right?).

Has anyone seen an actual transcript? If so do you have a link for it?

I'm curious if the controller did issue a turn direction. She certainly missed a readback that clearly says turn left which she is absolutely responsible to hear and correct. From the tapes though you cannot hear her issue a turn direction. She had lots of opportunities to help correct the entire situation and failed completely to do so. Just curious about the actual first clearance though

henra 25th Dec 2016 09:37


Originally Posted by ElectroVlasic (Post 9617848)
I don't think I'd go with "entire", but would say this thread seems to be fixated on radio terminology (which I can say is a pet peeve of this forum after reading it for more than a few years) and largely ignoring the fact that the crew was told to get to heading 180, and acknowledged that, and regardless of the issue regarding left turn vs right turn, flew heading 0.

Thanks!
I thought I was missing something because everyone was so fixated on the "Southbound" Radio stuff.
And I was wondering what on Earth was so complicated in understanding Heading 180, Turn Southbound plus knowing that closely North of LA since Thousands of Years there has been a huge Mountain range with lowest Elevations ~8000ft and chances are that won't have changed over Night.

Yes the comms were surely less than ideal. But I expect from Airline Pilots a minimum Situational Awareness. In this case it is so fundamentally clear that they were completely lacking any SA .
Normally I'm not happy if they hang the Pilots to dry as a PR measure. In this case I would support this. I surely wouldn't want to have these guys in the Cockpit of a plane I fly with.

RexBanner 25th Dec 2016 10:00


Originally Posted by Hotel Tango (Post 9619852)
I totally agree that a radar vector to 018 just wouldn't happen.

Precisely. ATC only work in five degree heading increments. A fact that is lost on many pilots who (for instance) report heading of 347 instead of common sense rounding to the nearest heading (345) which is all ATC are interested in anyway. Sorry to thread drift a little with one of my bugbears though.

Regardless of the lack of SA of the EVA crew (and that is clear) how can the controller escape censure for the way she dealt with this incident? Ambiguous instructions and, when clear that a lack of understanding has taken place, she continues to rabbit those same instructions in a frustrated tone in the expectation that something is going to change.

Hotel Tango 25th Dec 2016 10:29

ZOA ATC, No, there is no official transcript released as yet.

RedBullGaveMeWings 25th Dec 2016 12:01

I read somewhere the controller has been suspended. Is it true?

aterpster 25th Dec 2016 13:46

1 Attachment(s)
RedBullGaveMeWings:


I read somewhere the controller has been suspended. Is it true?
Reassigned to desk duty according to the Los Angeles Times. Article attached.

Uplinker 25th Dec 2016 14:00


Uplinker:
jumpx3 is very kind with you to explain how it normally works, , and he is 100% correct .
I am however a bit puzzled by 2 points in your reply :
Quote:
I have 16 years commercial passenger flying experience, including 10 years flying heavy twin jets (A330) longhaul
and
Quote:
I did wonder if EVA015 had suffered a compass malfunction,
Not really compatible I would say.
Hello ATC Watcher. I am sorry to have caused you puzzlement. So far, your contribution to this thread has mostly been regarding the 250 Kts below FL100 rule, and having a go at me. I wonder if you have actually read my posts carefully or just skimmed them? And have you listened carefully to the ATC tape? Judging by your attacks, it would seem that I am missing something obvious, so I would be interested to know what your theory is as to why EVA015, on being told "turn....[something].......heading 180", actually turned north and kept a heading just east of north all the way until it got to Mount Wilson?

I am very familiar with being given heading turns of more than 180 degrees, and in that event ATC usually says something like "left, left onto heading xxx degrees", or "all the way round to heading xxx", or " the long way round to heading xxx". If they don't, then I or my colleague will query the turn direction, just to be sure.

You dismiss my suggestion of a compass malfunction : Was it a Korean 747-400 that crashed out of Stansted UK whose PFD1 malfunctioned and the F/O did not query or take control out of apparent cultural deference to the Captain but just watched as the Captain followed his failed PFD and banked into the ground?

I completely agree; being given a heading of 018 degrees by ATC is most unlikely - they would say 015, or 020. I am merely trying to understand why EVA015 headed just east of north after being given a heading of 180? Was PF dyslexic or confused?

As far as EVA015 ignoring instructions; Well judging by ATC's comments and looking at the graphic:- after his initial incorrect turn, he did not act on any of the heading changes given by ATC until he got to Mount Wilson. That seems to me to be ignoring instructions. Had he not understood the instructions, then why did he not query them?

.

Airbubba 25th Dec 2016 15:40


Originally Posted by RexBanner (Post 9620289)
Precisely. ATC only work in five degree heading increments. A fact that is lost on many pilots who (for instance) report heading of 347 instead of common sense rounding to the nearest heading (345) which is all ATC are interested in anyway. Sorry to thread drift a little with one of my bugbears though.

That's a new one on me, not saying that you are wrong. What do you do if the controller says 'maintain present heading, say heading'? Stay at 347? Or turn to 345? Is this ICAO or FAA? Obviously a turn to anywhere close to a heading of 180 would have prevented a near CFIT in this case.


Originally Posted by Uplinker (Post 9620393)
Was it a Korean 747-400 that crashed out of Stansted UK whose PFD1 malfunctioned and the F/O did not query or take control out of apparent cultural deference to the Captain but just watched as the Captain followed his failed PFD and banked into the ground?

Actually, the 1999 KE crash out of Stansted was a steam driven 747-200 freighter, not a -400:

https://en.wikipedia.org/wiki/Korean...go_Flight_8509

oicur12.again 25th Dec 2016 15:45

The initial call from atc was turn left hdg xxx. These guys were a heavy crew with a significant cockpit gradient and most likely significant language barriers. It may have been a situation where the senior guy flying was releying on the junior guy using the radio to interperet the instruction. As i have seen before, this situation is a recipe for massive confusion in the cockpit. There may have been 4 guys all yabbering at each other with contradictory information, misunderstanding, concerns about terrain AND tcas traffic from the canucks.

None of us were there but i suspect that cockpit was one hell of a s%#¥ show for several minutes.

Hotel Tango 25th Dec 2016 18:35


The initial call from atc was turn left hdg xxx.
What is your source? Have you not read any of the previous pages of this thread?

There is at present NO official evidence that the controller said left 180. The only tx heard is the read back from EVA which says "left". I do not consider a newspaper article as official evidence.

RexBanner 25th Dec 2016 18:42


Originally Posted by Airbubba (Post 9620430)
That's a new one on me, not saying that you are wrong. What do you do if the controller says 'maintain present heading, say heading'? Stay at 347? Or turn to 345? Is this ICAO or FAA?

You maintain heading as instructed and report it as 345. When was the last time you heard any vectors from Air Traffic Control ending in anything other than a zero or five? ATC only work to the nearest five degrees (two degrees difference - which is the most it will ever be provided you've rounded the right way - isn't going to make any difference and in the unlikely event it does, ATC can give you a further heading change). I've had this discussion with controllers many a time.

Epic thread drift, which is what I feared by making the comment in the first place, so apologies!

donotdespisethesnake 25th Dec 2016 18:49

Flight controller accidentally sends jet on course toward Mt. Wilson after LAX takeoff - LA Times

Bound for Taiwan, the EVA Air Boeing 777 took off to the east early Friday from Los Angeles International Airport’s south runway complex, according to FAA spokesman Ian Gregor. After takeoff, the air crew switched from the LAX control tower to the approach control operations in San Diego, which Gregor said was common practice.
“The air traffic controller at the approach control who was handling EVA instructed the pilot to make a left turn to a 180-degree heading,” he said. “She meant to tell the pilot to make a right turn to a 180-degree heading.”
Following the controller’s instructions, the pilot turned left.

Check Airman 25th Dec 2016 19:32

I'm putting the blame on the pilots here. Yes the controller may have given an initial left turn to 180, but as a pilot, my reply would have been "confirm LEFT turn 180" or (non-std) "left turn 180, long way around". I'd like to think that anyone with a bit of SA would have said something similar.

The only bit of the ATC transmission that didn't make sense to me was the left turn to 270/290- towards ACA788.

On the "southbound" comment, perhaps she used to work at a VFR tower before, but it's quite common RT to hear when handling VFR traffic. "Fly southbound to join the final for runway 9".

On the use of "southbound" vs "180 degrees"- I'm not sure if it's the way they're trained, but I've observed that quite often, when dealing with disoriented pilots, ATC will sometimes revert to cardinal directions. I'd like to think that despite a different culture, "turn south now" is pretty clear.

Someone else suggested "stop your climb" is ambiguous. I disagree. It isn't at all. If that instruction is given, in my experience ATC needs it done immediately. Just level off wherever you are. How is that ambiguous?

Airbubba 25th Dec 2016 19:41


Originally Posted by RexBanner (Post 9620511)
You maintain heading as instructed and report it as 345. When was the last time you heard any vectors from Air Traffic Control ending in anything other than a zero or five? ATC only work to the nearest five degrees (two degrees difference - which is the most it will ever be provided you've rounded the right way - isn't going to make any difference and in the unlikely event it does, ATC can give you a further heading change). I've had this discussion with controllers many a time.

Maybe that's how they do it some places but not here in America. ;) If ATC asks you to say heading, you are supposed to give the actual aircraft heading, not the nearest five degrees. If you are asked to say altitude you do round it to the nearest 100 feet if you are climbing or descending, however.

And, if you're given runway heading on runway 4, you maintain the actual mag heading of the runway centerline, e.g. 044, not 040.

Hope this helps. :ok:

COflyer 25th Dec 2016 21:30

Language/phraseology may have been a contributing factor, but the EVA crew were largely at fault here. They were not situationally aware and turned North toward terrain without clearance and ignored repeated ATC requests to turn right to a heading of 180.

Ushuaia 26th Dec 2016 07:02

They were NOT repeatedly told to turn right unless we are listening to different tapes.

They were told to turn LEFT, then RIGHT, then STOP THE CLIMB!, then turn LEFT. Thereafter they were told repeatedly turn SOUTHBOUND. Repeatedly.

They didnt know which direction the controller wanted them to turn to achieve that! There's been a near miss as far as they know and the last direction given was LEFT. So they hesitated.

Poor SA on the crew's part re terrain, yes, but the controller really blew the thing up with the "LEFT ONTO 29... CORRECTION 270 " followed by "TURN SOUTHBOUND"

She managed to use the word RIGHT with the other callsigns on frequency, but not with EVA when they needed it most. Just SOUTHBOUND, SOUTHBOUND. "Which WAY do you want us to turn to achieve southbound?" these guys were thinking in two languages. You hear the confusion when they say "LEFT...RIGHT?"

henra 26th Dec 2016 09:20


Originally Posted by Ushuaia (Post 9620764)
They were told to turn LEFT, then RIGHT, then STOP THE CLIMB!, then turn LEFT. Thereafter they were told repeatedly turn SOUTHBOUND. Repeatedly.

Sorry but the Key Instruction they were given is "180" and "Southbound". REPEATEDLY. What part of 180 is so difficult to understand?
The 1? The 8? Or the 0?
Turn Left to 180 would have meant a 270° turn to the left towards 180°. What on Earth made them go for a Course 0? I haven't seen any request in that direction.

What is so difficult to understand in "Southbound"?? How many "South's" did they have on their Compass?

Yes, the Controller delivered a less than stellar performance, much less than stellar and surely initiated some confusion.



But the real major :mad: Up was clearly by the Crew.
I absolutely expect an Airline Pilot to be able to distinguish between Course 0 and 180. And I expect him not to mentally fall apart as soon as anything goes a little bit different than expected.

Ushuaia 26th Dec 2016 10:42


Originally Posted by henra (Post 9620830)
Sorry but the Key Instruction they were given is "180" and "Southbound". REPEATEDLY. What part of 180 is so difficult to understand?
.......

What is so difficult to understand in "Southbound"?? How many "South's" did they have on their Compass?
......

The difficulty/confusion was the DIRECTION OF TURN to get there. Left? Or right? Left is towards traffic they have just been told STOP CLIMB! for and Right is towards high ground - and they've been levelled off.

The controller has told us to turn LEFT then RIGHT then LEFT. Which way does she bloody-well want us to turn to get southbound? The most recent direction was left - does she mean go that way? Or the more direct way which is right?

When faced with two diametrically-opposed options, the human reaction is often to do nothing. Human Factors stuff. You need to clarify, and do so quickly.

Can you blokes truly not put yourself in that cockpit and picture this confusion?

I have 15,000 hours of 744/767/737 experience and I can picture this - how one insidious mistake is compounded by further factors and the whole thing can go pearshaped in a matter of minutes.

I really do wonder about the real world flying experience of some of the Monday morning quarterbacks around here who assert that this was primarily the crew's fault. Walk a mile in his shoes, etc etc

henra 26th Dec 2016 12:16


Originally Posted by Ushuaia (Post 9620891)
The controller has told us to turn LEFT then RIGHT then LEFT. Which way does she bloody-well want us to turn to get southbound? The most recent direction was left - does she mean go that way? Or the more direct way which is right?


Then ask the bloody question but don't continue in a direction with a known huge accumulation of big Cumulu Granitus and in opposite direction to the Course given by ATC, FFS.


How did they end up with Course 0 instead of 180 in the first place? And that was long before Left, Right...

aterpster 26th Dec 2016 13:02

henra:


Yes, the Controller delivered a less than stellar performance, much less than stellar and surely initiated some confusion.
She immensely compounded her incorrect instruction by focusing on separation of EVA from Air Canada. She did this to exclusion of terrain clearance, which she permits to become a near fatal event. KLAX is only 125 feet above sea level. It is only 23 miles to terrain and obstacles nearly 7,000 feet above sea level. It is only 18 miles to the point where the minimum vectoring altitude (MVA) is higher than EVA's achieved altitude. Keep in mind he had ask for and been granted a "high speed climb" (which is not an approved ATC procedure in the U.S.)

In any case, she became fixated on airplane-to-airplane separation to the exclusion of the pending rising terrain disaster. Once EVA entered the MVA area of 7,700 that surrounds Mt. Wilson, the controller became a passenger. She may have well been in the lunch room for all the good she could do by that point. It's a no-mans land when she has an airplane some 2,000 feet below MVA. Yes, she has an emergency map called the Emergency Obstacle Video Map (EOVM), which provides only 300 feet of obstacle clearance, but which does not have the resolution or fidelity to avoid a ridge line or a massive array of tall antennas.

Her blunders, compounded by a much more serous blunder, did not result in a catastrophic aviation disaster essentially only because the dice rolled in her favor.

I've worked with issues of instrument flight procedures and associated terrain clearance issues for many years. MVAs in mountainous areas have always been a very weak link in the safety chain with the FAA. In the year 2016 it is as bad as it was 50 years ago when you factor in a weak air traffic controller and a crew not familiar with the area.

This woman should find another line of work. But, the FAA will simply decertify her, send her to Oklahoma City for remedial training, then she will be back at the scopes.

And, the "cops" will have by then finished their investigation of themselves. (No conflict of interest there.)

henra 26th Dec 2016 14:20


Originally Posted by aterpster (Post 9620985)
This woman should find another line of work.


I absolutely agree. She seemed to be not up to the task from a mental strength perspective.
She quickly collapsed with a situation that started with a small lapse. From tiny Error to full panic mode within a few seconds and with no immediate danger present. Someone working in ATC at an Airport like LAX needs to be much much more resilient and stress resistant. Something which can't be fixed with a little bit more training.



But, the FAA will simply decertify her, send her to Oklahoma City for remedial training, then she will be back at the scopes.

Hopefully not. Maybe she gets the hint by herself that this profession isn't for her.

golfyankeesierra 26th Dec 2016 14:53


This woman should find another line of work
I absolutely don't agree; she did not turn up at work to do a bad job.
She wouldn't be there in the first place if she weren't a first class controller anyway.
But I agree that she did mess up big time!
So I would like to repeat my post of 5 days ago on this thread:

Perhaps she was having a bad day, perhaps it was the end of a long day.. (we have all been there, done that..)
But!
Safety should not be depending on a single person. Where was the supervisor?
There should be more then one layer of cheese.. This looks to me like a fault in the system; going to be an interesting investigation and a very interesting read HF wise...
A lot to learn here (again), pilots and controllers alike..

There would be a lot more smoking holes if we were in the cockpit alone..
Where was her backup? :=

Bedder believeit 26th Dec 2016 15:59

Forty plus years ATC here, Sydney, Dubai, Kai Tak, Chek Lap Kok, and it never ceased to amaze me how many of my ATC colleagues from North America that I worked with, somehow managed to get things confused. Culturally many of them could not flatten down the Americanisation of their personalities to Keep It Simple Stupid. Now before I'm jumped on, I did use the word "Many" and I did not use the word "all". I'll also add that the "good" North Americans were very good. That sheila was bloody hopeless.

Airbubba 26th Dec 2016 16:41


Originally Posted by Bedder believeit (Post 9621107)
I'll also add that the "good" North Americans were very good.

'North Americans' is often a code phrase for Canadians in my experience. It doesn't mean Mexicans. Beware cheap imitations from the Great White North. And never get between a Canadian and a Walmart in the lower 48. ;)

Kinda like when someone says they are a 'pilot with a major airline', it usually means a commuter or freight dog FO. And when they are a 'consultant', it often means that they are between flying jobs. :)

But, mentioning Hong Kong, you can see vast cultural differences in say, the departures out of HKG and those out of LAX, both with significant terrain in the area. We Americans like simplicity in aviation. But I do agree that we need to do much better with our ATC phraseology in the international realm.


Originally Posted by aterpster (Post 9620985)
This woman should find another line of work. But, the FAA will simply decertify her, send her to Oklahoma City for remedial training, then she will be back at the scopes.

She certainly won't be fired. And, if it is like some cases over on the pilot side, she may be able to get a settlement and be paid not to come back to work.

RatherBeFlying 26th Dec 2016 16:59

What does the controller really want
 
The cockpit crew was understandably confused as to what the controller wanted, especially when the initial compliance to instructions produced a confusing series of contradictory instructions from the controller.

Even native English speaking pilots can have difficulties when a controller pulls something unusual out of the hat - as I have had in my own country.

We don't know yet if terrain considerations were addressed in the cockpit, but it seems they were concerned about traffic .

It would be interesting to throw random selections of PPRuNers into a sim with the ATC tape and score the damage to the antenna farm along with Snitch alarms.

COflyer 26th Dec 2016 17:55

I guess we are all using the same Real ATC recording from the 1st post on this thread.

From the recording it's unclear why EVA 15 made the left turn northbound, but lets assume for sake of argument that the controller did indeed make an error and issue the left turn the EVA crew confirmed. However, as soon as the controller saw them turn left she issued an unequivocal correction:

SoCal Departure: „..turn right, turn heading 180.„
EVA 15: „Copied, right heading 180, EVA 15 heavy.„
SoCal Departure: „..please expedite your right turn.„
EVA 15: „EVA 15 heavy, roger just passing heading 010, continue right turn heading.„

Pretty clear to me.

But for whatever reason, they didnt continue the turn to 180 as instructed but appear to have maintained their 010 heading setting up the conflict with Air Canada 788 and getting ever closer to terrain.

Why are we blaming the controller?

Ushuaia 26th Dec 2016 19:59

They didn't continue a turn right, COFlyer, because they were suddenly told "STOP YOUR CLIMB!", closely followed by "TURN LEFT HEADING 29 CORRECTION 270."

Ushuaia 26th Dec 2016 20:27

I too hope this lady gets back to work soon, as well as the crew if it's true that they were stood down too. I have no doubt they are all proud professionals.

Even the very best people make mistakes. These days we don't simply discard such individuals; we evaluate errors, work out improvements, do retraining and get people back in the saddle if they're up to it. Besides, the system is more than just one individual: they need to look at the what supervision was happening in SOCAL that day, what oversight of "the big picture" was going on. That's more than this one lady.

We are all on the same team; just got to get the team working together and running down the field in the same direction.

172_driver 26th Dec 2016 20:30

I don't trust the ADS-B plot to perfectly reflect turns. Ian W mentioned that it could be up to 30 sec. (Worst case) before a turn is seen on the radar scope. But it's something like 21 nm, mesaured on Skyvector, from the point where they're heading for Mt. Wilson to Mt. Wilson. What happened during those 21 nm?? Even at 360 kts over the ground, it's 3,5 min. No sign of a turn.

I can agree it would be better by the controller to keep direction of turn to the same direction, as the autopilot (which i am sure was never disconnected) can be quite sluggish.

Stone69 26th Dec 2016 20:44

This whole " incident " is a fiasco and the controller is not the only one that should be under scrutiny. I think the front end crew didn't have a clue. Why in hell would they allow the speed to be in the 330 to 360 range as they head toward the high ground ( mountain ) .....I seriously doubt they even knew of the high ground until the GPWS started going off....

henra 26th Dec 2016 20:46


Originally Posted by Ushuaia (Post 9621274)
I too hope this lady gets back to work soon, as well as the crew if it's true that they were stood down too. I have no doubt they are all proud professionals.


Hmm, dunno. It is not so much the error made (that was a rather minor one -can happen) that shocks me but the total collapse of structure on both sides following that small hickup.
The pilots seemed to have frozen and merrily continued towards the Mountains on opposite direction to the one given by ATC even after repeated requests to turn even if erratic in detail. All this in a relatively benign (at least initially - they let it become critical by no structured action for several minutes) situation.
The controller got into panic mode a few seconds after she made a minor mistake.
Both showed personality traits that are profoundly worrying in their respective profession. And this cannot simply be fixed by a few hours training. I would not want to think about what all of them would do in a direct emergency situation. Resilience should be a top personality criterion in both professions: Airline Pilot and ATC.

aterpster 26th Dec 2016 23:09

172 driver:


I don't trust the ADS-B plot to perfectly reflect turns.
No doubt about that. But, it generally shows what happened. The FAA has great data, though, but we will never see it because, alas, the NTSB didn't get involved.

The SoCal TRACON, like all FAA mega-TRACONs has Fusion radar; i.e. all the radars they are using are in a matrix. Their radar recordings are impressive, no doubt. But, since the FAA is investigating itself, those data will not see the light of day.

DaveReidUK 26th Dec 2016 23:34


Originally Posted by 172_driver (Post 9621276)
I don't trust the ADS-B plot to perfectly reflect turns. Ian W mentioned that it could be up to 30 sec.

ADS-B is not subject to any appreciable delay.

If all the packets it transmits are captured, the resulting plot of the turn will be far more accurate than radar, and as near to real-time as makes no practicable difference.

172_driver 26th Dec 2016 23:46

Ok, makes it even stranger that an airplane is plotted tracking north for 20 odd miles while repeatedly instructed to turn south.

aterpster 27th Dec 2016 00:49

172 driver:


Ok, makes it even stranger that an airplane is plotted tracking north for 20 odd miles while repeatedly instructed to turn south.
An Asian crew in disbelief (understandable) and a controller overloaded with only 2 or 3 airplanes in normally quiet airspace at that early morning except for the fact that LAX is east at the time, which requires a better skill set on the part of the controller for the unusual.

DaveReidUK 27th Dec 2016 06:32

FR24 health warning
 

Originally Posted by Airbubba (Post 9621421)
And, if some packets are missed, you do get a few herky jerky turns in areas of poor coverage as the FR24 constant velocity Kalman filter attempts to connect the dots.

No argument there, although I wasn't aware that FR24 used any kind of estimating algorithm other than crude extrapolation and dumb joining-the-dots.

That's why a track on the map is only useful given a sufficient plot density and, preferably, timestamps for each point.

Ironically, given the current context, the worst example I've seen was where FR24 turned a lazy 270 into an instantaneous 90 in the opposite direction ...

DaveReidUK 27th Dec 2016 06:51


Originally Posted by Airbubba (Post 9621421)
Another plot may be found on this LAX nimby noise page:

WebTrak

Set the date for 12/16/2016 and the time for 01:19, the local takeoff time of the Eva flight to see the aerial ballet toward the mountains.

Plot from WebTrak, showing both the EVA and Air Canada:

http://www.avgen.com/EVA015.jpg


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