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Boeing 777 departing Dubai nearly had a major incident after takeoff

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Re: Boeing 777 departing Dubai nearly had a major incident after takeoff

#201

Post by kergonath »

mulmen wrote: post #185
usrusr wrote: post #126

Earlier quoted context omitted.

Ironically the metric system suffers the same theoretical "error" as the not-an-arc-minute-anymore NM because the meter was originally defined by taking the distance from pole to equator (to the best of their knowledge at the time) and then shifting the decimal point to get something human scale.

> to the best of their knowledge at the time I think it was actually extrapolated from a survey of the length of France. No idea how they did that extrapolation.

Initially, yes. The story itself is quite fascinating, and the Wikipedia page on the metre is a good starting point.

This was a hot topic during the 19th century as different improvements in the techniques and devices used to measure the Earth showed that the first measurements were imperfect, however good they had been at the time, and that the whole idea is not workable because the Earth is not a sphere. This lead to the formal definition of the metre as the length of a prototype in 1889.

Re: Boeing 777 departing Dubai nearly had a major incident after takeoff

#202

Post by sitharus »

thewarrior wrote: post #167
SkyMarshal wrote: post #49

Earlier quoted context omitted.

> It doesn't matter was in system. You run your checklists and configure for your own flight / your own departure etc. I am not a pilot, but that's exactly what I thought when I read the memo too. They should be putting responsibility for the next flight on the next flight's crew, not the prior flight's crew. Train each crew to assume the plane they're prepping for their next flight is FUBAR in every way, checklist e…

I know nothing about aviation but it seems to me like the auto pilot software could use a lot of improvement. Why on earth would you give the pilot an instruction that would almost certainly lead to a crash ? It seems like there aren’t enough sanity checks. Any such dodgy situation should trigger an alarm and disengage the auto pilot imo.

Auto pilots disengaging and sounding an alarm in unexpected situations have lead to multiple crashes, also the autopilot wasn’t engaged at the time, but the pilot was following a computer created flight path.

Commercial aviation is designed around highly trained people following defined procedures. Auto pilots are not supposed to second-guess the inputs because that adds to confusion and cognitive load on the pilots. Pilots tell the computer what to do, not the other way around.

What _should_ have happened here is the pilot monitoring should be watching the instruments and calling out flight stages. When the pilot flying didn’t initiate a proper climb they should have called this out, or taken over control until a safe altitude was established. This wasn’t an autopilot issue, this was a breakdown on crew resource management.

Re: Boeing 777 departing Dubai nearly had a major incident after takeoff

#203

Post by dylan604 »

sokoloff wrote: post #43
HeavenFox wrote: post #34

Earlier quoted context omitted.

You don't take off with 30 degrees of flaps though, fortunately.

Correct. This was likely a flaps 15° (or maybe 20°) departure (being a heavy departure).

262 is still too high for either of those flap positions according to the above list. So while you may be correct with your comment, it is pretty much without point???

Edit: At least for the topic of this discussion. However, I'll now be able to win a bar bet when someone aks what flaps position for a heavy take off of a 777 would be

Re: Boeing 777 departing Dubai nearly had a major incident after takeoff

#204

Post by dehrmann »

EMM_386 wrote: post #120
onphonenow wrote: post #16

The memo from Emirates about not setting altitude in system to airport altitude is so weird. I really hope that's not the actual message Emirates is putting out there. It doesn't matter was in system. You run your checklists and configure for your own flight / your own departure etc. Memo should be to training / recruitment - where did you find these pilots to fly a 777? So they obviously didn't pre-flight the flight…

It's unbelievable that the pilot's didn't realize they were doing 215 knots while still ON THE GROUND and only decided to pull back on the yoke once they were nearing the end of the runway. They should have at least seen the end of the runway coming up and wondered why they weren't airborne yet. The ends are colored in amber and red as it gets closer to the end, it should be pretty obvious something is wrong. Pull ba…

> How you get to this level of incompetence flying a 777 is far beyond my understanding.

The article said--it's the smallest plane Emirates flies.

Re: Boeing 777 departing Dubai nearly had a major incident after takeoff

#205

Post by jcrawfordor »

jakub_g wrote: post #136

Can someone ELI5 why the plane was not gaining altitude despite higher-than-usual speed? (The physics behind it) The autopilot set to the lower-than-current altitude effectively set the flaps into descent mode so it needed higher speed than usual to start climbing up? Also how come it finally started getting altitude even with destination altitude being zero?

Roughly speaking, if you push forward hard enough the plane goes down. There are limits to that of course, but in this case the FD wanted to maintain an altitude of 0 so it was "suggesting" a downwards pitch to the pilot, and the pilot was doing as told. The FD is only an advisory system, it basically lets the pilot choose a goal and then it shows on the attitude display where to point the nose to achieve that goal. It helps pilots to be more efficient and precise and, in theory, avoid errors. In this case though it was misleading and apparently the pilot did eventually realize that and stop following it, but very very late, after other indications like high airspeed and the view out the window would have strongly suggested that the climb was not going as intended.

Re: Boeing 777 departing Dubai nearly had a major incident after takeoff

#206

Post by Pasorrijer »

ComputerGuru wrote: post #137
Pasorrijer wrote: post #101

Earlier quoted context omitted.

My personal list is Tier 1 US, Canadian, British and German carriers as well as Qantas. Probably throw Air France and KLM in too. In Africa, Ethiopian would be the only airline I would fly if I had to fly an African airline. I probably would have had a middle eastern airline on the list before I did a project with them last year. After that, I learned a lot that made me stick to the list above.

> I probably would have had a middle eastern airline on the list before I did a project with them last year. Does this include One World/Star Alliance members?

I honestly don't know enough to have an opinion. I'm personally a fan of Star Alliance, but I don't know enough about the middle eastern airlines.

I DO know that even the airlines in NA/Europe etc. have their own share of... Challenges.. And a lot of those are saved by the regulatory / operating environment / culture, and those safeguards don't necessarily always exist elsewhere in the world.

Re: Boeing 777 departing Dubai nearly had a major incident after takeoff

#207

Post by blinkingled »

ohazi wrote: post #36
blinkingled wrote: post #18

TL;DR - Don't screw with the defaults (MCP) after landing, especially when it's unnecessary and when the next takeoff crew likely will not remember to set it to proper value before takeoff. I wonder if this is not a detectable condition for the flight software - maybe in some cases you want the MCP to be set to low? Otherwise autopilot could either auto correct it or issue a warning?

This was 100% pilot error. You don't ever "follow the flight director" to determine when to rotate, you use the airspeed indicator.

Sure, but the TL;DR was the approach Emirates took - they literally communicated that to the crew and I can't say I disagree with it - why add to process/work if you can leave it at a sane default? (Unless I misunderstand - which is why my question.)

Re: Boeing 777 departing Dubai nearly had a major incident after takeoff

#208

Post by teeray »

thewarrior wrote: post #167
SkyMarshal wrote: post #49

Earlier quoted context omitted.

> It doesn't matter was in system. You run your checklists and configure for your own flight / your own departure etc. I am not a pilot, but that's exactly what I thought when I read the memo too. They should be putting responsibility for the next flight on the next flight's crew, not the prior flight's crew. Train each crew to assume the plane they're prepping for their next flight is FUBAR in every way, checklist e…

I know nothing about aviation but it seems to me like the auto pilot software could use a lot of improvement. Why on earth would you give the pilot an instruction that would almost certainly lead to a crash ? It seems like there aren’t enough sanity checks. Any such dodgy situation should trigger an alarm and disengage the auto pilot imo.

By my reading, auto pilot was not involved. Flight Directors are basically an overlay on the instruments showing where the pitch, roll, etc. of the plane needs to be to achieve the programmed navigational fixes.

Re: Boeing 777 departing Dubai nearly had a major incident after takeoff

#210

Post by dehrmann »

bronco21016 wrote: post #147
bambax wrote: post #72

Earlier quoted context omitted.

Great video, thanks. I find it weird that we learn so little about aviation when the industry has so much to teach us. The checklist manifesto was a great attempt to try to implement checklists in the hospital and other places, but from CRM to workload management there is so much to benefit from what the airline industry has pioneered.

As someone who works in the airline industry I find it infuriating when other industries don’t match my expectations. I saw behind the curtain at a couple of medium sized online retailers. The lack of process and procedure was just astounding to me. I know some airline pilots have had success in consulting in hospitals but maybe there exists a broader market for that service.

You can get a way with a lot when accidents don't cost a billion dollars.
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