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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

#171

Post by jillesvangurp »

nradov wrote: post #9
Daishiman wrote: post #2

Why are knots used in aviation over kph?

Using knots made navigation calculations easier with paper maps marked in degrees and minutes. A nautical mile is the same as a minute of latitude, and a knot is one nautical mile per hour. Now with electronic navigation systems kph would be just as easy, but aviators are all used to thinking in knots so changing would be difficult.

It's partly true. However, a lot of planes outside of the US would have used kilometers per hour historically. For example German WW II planes did that. Likewise a lot of Russian cold war era planes did the same. And lots of modern planes (e.g. French ones) still do. And some planes in the US actually use miles per hour instead of knots; especially in general aviation.

It's just that post war, the US aviation industry was very dominant and the metric system never was popular there. For the same reason feet are used instead of meters for measuring altitude. And unlike with nautical miles, there's not much of an advantage for that. However, the units for altimeter settings are metric (i.e. millibar instead of inches of mercury) in much of the world except in the US.

For flight controllers and procedures they had to pick a unit for flight levels that everybody understands in the same way and since the US aviation industry after WW II pretty much dominated, a lot of planes would have used feet. Internationally, flight levels are used everywhere above certain altitudes. Those are basically feet divided by 1000 (kilo feet?, LOL). So, FL 29 would be 29000 feet at 29.92 inches of mercury in the US and 1013.2 millibars in the rest of the world.

The Russians actually used meters until very recently apparently and only switched to feet a few years ago after of course first supporting flight levels. And apparently, the Chinese still use meters: https://ivao.aero/flightops/divprocedures.php?id=CN and planes must actually be capable to switch their altimeters to using meters to fly in China. Likewise, North Korea uses meters apparently.

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

#172

Post by encoderer »

throwanem wrote: post #158
kayodelycaon wrote: post #144

Earlier quoted context omitted.

I thought all takeoffs were manual. Is auto-takeoff out of testing already?

The takeoff isn't directly automated, but there's a system called the "flight director" [1] that provides indicators on the pilot flying's display that correspond with a configured trajectory. In this case, it sounds like the flight director was badly misconfigured and the pilots not only omitted to reconfigure it, but followed the erroneous indication far past any point at which it was remotely reasonable (or remote…

So this is the airline equivalent of Michael Scott following his gps into the lake?

Insane

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

#174

Post by jcrawfordor »

mulmen wrote: post #77
jcrawfordor wrote: post #50

Earlier quoted context omitted.

Really depends on the context. Usually things that were designed for pilots to use will display ground speed in knots since it's likely the pilot will be comparing against calculations done in knots. Things that were designed for the general public usually show mph since most people don't have a good sense of how fast a knot is. Taxi speeds are always written in knots, so I suppose you could say it is "official" (in…

> So that when kph/mph is heard a pilot knows they're referencing ground speed, whereas knots is air speed. Who is using MPH/KPH in the course of flying a plane? Why would this ambiguity resolve to “that must be ground speed”? Why would there be ambiguity in a speed readout at all? Surely context and procedure should disambiguate this rather than units?

I'm not actually sure where that quote came from, but yes, there's not likely to be much confusion. Ground speed is usually displayed by some kind of computer, could be a glass panel or just an aviation GPS unit, and is usually marked "GS" or "Kts Ground." And it's sort of considered, philosophically, to be more a navigation thing than an actual flight instrument, since you only really pay attention to it in flight if you're doing navigation calculations.

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

#175

Post by alamortsubite »

Simon_O_Rourke wrote: post #114
omegant wrote: post #82

Earlier quoted context omitted.

It goes way beyond checklist stuff. Imagine having an intermediate system in your Tesla, one between fully manual and the autopilot. This system uses the navigation capabilities of the autopilot to draw in the big screen some squares that guide you to your destination without the need to look outside. Something you may find in a videogame. This system is helpfull and easy to use, and allows you to pay attention to mo…

I would like to know what the Ryanair pilots are ordered to do by their higher ups. Been on a few of them in Europe and they all hit the runway pretty hard coming back down.

Navy pilot vs Air Force pilot.

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

#176

Post by quacked »

ytdytvhxgydvhh wrote: post #163
cybertronic wrote: post #161

Earlier quoted context omitted.

Adding at the end: " ... So, these pilots were ill trained and negligent. Don’t fly on these types of carriers. I don’t."

I wonder what “these types of carriers” means here. I know there are low-cost carriers and I wouldn’t be surprised if they had less-experienced pilots, etc. But to me Emirates strikes me as a well-funded, reputable operation. Does he mean Middle Eastern carriers?

If the country you're in:

- Prioritizes "face" or "reputation" above literal accuracy - Has lower-level officials that accept bribes - Has had airlines and planes for fewer than 5 decades

Assume any complex high-risk engineering system run by that culture will occasionally fail in major ways.

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

#177

Post by crooked-v »

tshaddox wrote: post #139
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’m not a pilot either but I am shocked that there’s not some standard “reset” procedure so that each flight starts with the plane in a consistent clean slate. It seems bizarre for any process to rely on the previous flight coincidentally leaving the plane in a certain state.

That's what pre-flight checklists are for. Even a "simple" one for a small plane like a Cessna 172 comprehensively covers setting or resetting literally every control in the plane.

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

#178

Post by goodcanadian »

yosito wrote: post #166
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…

> What was pilot monitoring doing during all this? Wouldn't there also be a copilot who is double checking this stuff?

There is a pilot and a co-pilot. At any given time in a flight, one will be the "pilot flying" and the other will be the "pilot monitoring." That is exactly the point of the quote: there are two in the cockpit, and one should always be checking what the other is doing.

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

#180

Post by nexuist »

jacquesm wrote: post #145

On another note: I think that having Boeing 777 in the title here is a bit misleading, this was an Emirates aircraft and Boeing had nothing to do with this incident. Suggest replacing 'Boeing 777' in the title with 'Emirates aircraft'

I'll play devil's advocate and suggest that it is a systems error that the 777 accepted an altitude of 0 without sounding an alarm or at least requiring prior confirmation. It shouldn't be that easy to almost total the airplane.
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