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Emirates B777 gear collapse @ DXB?

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Old 9th Aug 2016, 10:11
  #681 (permalink)  
 
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A pull up manoeuvre is a bad idea as you would need to pull the nose up to 20 degrees
No, only up to stick shaker, which might be very much lower initially and which incidentally gives the actual best performance getting away from what is the greatest threat: The ground.

Isn't that the foremost objective when you're hanging in the air, close to ground?

It might sound strange, but such bounced/balked landings, if due to pilot error or ambient conditions, were what brought the three MD11 down and now a -300. All of them seemingly tried the procedure with holding actual attitude and then trying to go around .....

I can see the reluctance to propagate such a drastic manoeuvre, but it seems to me, that drastic situations sometimes require drastic measures.

.... and it's just a suggestion ....
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Old 9th Aug 2016, 10:32
  #682 (permalink)  
 
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The experience, training and procedures are all there and, in many airlines throughout the world, are in practice.

It's just getting the airline management to stop seeing training purely as a cost to be trimmed to it's absolute legal minimums and see it as a forward projecting benefit to the company. Apply the experience, procedures and training that we already possess!
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Old 9th Aug 2016, 10:50
  #683 (permalink)  
 
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up to stick shaker, which might be very much lower initially and which incidentally gives the actual best performance
The stick shaker gives you a predfined margin to stall, but that only accidentially would mean it is the speed of steepest climb. You may already fly slower than the best climb performance speed if you pull up to the stick shaker.
However, If you do not have time to figure out the best speed, pulling up to the stick shaker is not totally off.
The speed of steepest climb is related to engine power, the stall speed is not. So that difference varies with OAT and wind. A clever modern PFD should be able to display it accurately...
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Old 9th Aug 2016, 11:08
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Pulling up to the PFI's is the EGPWS pull up go-around manoeuvre and whilst it will give you the most rapid of climbs it also can activate the stick shaker which is a huge distraction to both crew members especially when so close to the ground!

Call the Go-Around, PNF selects F20, a smooth application of pitch at 2-3 degrees per second towards 15-20 degrees at landing weights with simultaneous application of full manual thrust, both engines functioning whilst monitoring the airspeed and vsi will take you between 5-7 seconds, hit the TOGA switches and follow the FD's.

Throw a stick shaker in there and your workload has gone through the roof. This is not a tricky manoeuvre from a flight position you are unsure of (unlike EGPWS!)

IMHO of course! :[
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Old 9th Aug 2016, 11:12
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Originally Posted by M.Mouse
That is not how the sytem works.
You are right, my mistake it should say:
pushing the TOGA switches leads to selection of go-around thrust guaranteeing a vertical speed of at least 2,000 ft/ min, automatic disengagement of all of the previously selected AFDS modes, and automatic engagement of the go-around roll and pitch modes. Pressing a second time leads to selection of maximum thrust.
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Old 9th Aug 2016, 11:14
  #686 (permalink)  
 
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pushing the TOGA switches leads to selection of go-around thrust guaranteeing a vertical speed of at least 2,000 ft/ min, automatic disengagement of all of the previously selected AFDS modes, and automatic engagement of the go-around roll and pitch modes. Pressing a second time leads to selection of maximum thrust.
Exactly! :-D Hence the requirement during the climb to review and reselect lateral modes as required. Hdg Sel, LNAV etc.
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Old 9th Aug 2016, 11:18
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Originally Posted by bobdxb
EK pilots don't use A/P on for LDG's unless it is autoland LDG required to keep recency and knowing the wx conditions at the time of arr that was the case.
Personally I would also disengage A/T at the same time.
Sorry, I should have been more specific. I meant the FD part of the A/P. By disengage, do you mean turn off the A/T switches or are you saying that the A/T will not respond to the TOGA switches with the A/T switches armed when in the air? (before or after a bounce)
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Old 9th Aug 2016, 11:31
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A/T disengage switches are on either side of the thrust levers. Pressing TOGA will re-engage the A/T as will selecting the A/T switch on the MCP or selecting FLCH.

TOGA after a bounce will not re-engage A/T as the switches are inhibited for 5 secs. If A/T is off then the pilot has manual thrust control, if A/T is active then the thrust will be being commanded to idle. If you push the throttles forward and release them A/T will command them back to idle again!
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Old 9th Aug 2016, 11:34
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Anyone remember the Jetstar incident back in 2007 involving an A320 where a go around was attempted but TOGA didn't engage and the aircraft kept descending and got within 38' of the ground ? This could have had the same ending as the EK incident but on this occasion the holes in the Swiss cheese didn't all line up.

Parallels can be drawn between the two occurances even though they involved different aircraft manufacturers and happened seven years apart.

The two engined go around receives far less attention than the single engined one, possibly as it is assumed to be a routine manoeuvre which should be well within the capability of any crew. A visual approach was regarded in a similar manner until the Asiana crash.

Perhaps simulator training needs to revisit the basics more often. Back in 1973 D.P. Davis was complaining in "Handling the Big Jets" about pilots who had forgotten how to fly.

Jetstar makes changes after go-around mishap | Australian Aviation
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Old 9th Aug 2016, 11:38
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Don't forget that there is also a variation in ticket prices. As a pilot it frustrates me when I see ticket prices that will barely cover the cost of the fuel for that sector. The effectiveness and size of the training department, the quality of candidates attracted by salaries, the number of tasks completed on Engineering checks, the number of pilots per airframe etc are all elements that affect the bottom line.
If Airline A has ten people in their training department, pays pilots the minimum they can get away with considering the market, runs the bare minimum tasks per Engineering check that the manufacturer allows and has pilots flying the maximum number of hours per month/ year that is considered legal, and offers cheap tickets, then Airline B who has a bigger more expensive training department ( ie better trained staff) , runs an extra 200 tasks for the same Engineering check, and has more pilots per airframe allowing well rested crews to operate at their best is stuffed. They have to compete on the price of the ticket, but their overheads are greater.
The "lean operators" drag the other operators down to their level. The only way to combat this is to have sensible minimum standards legislated. Unfortunately, the regulators don't often meet with pilot/ engineering groups ( those who understand the realities of safety) , they meet with the lawyers and accountants who run the Airlines and come up with rules like the recently introduced duty and flight time limitations that can see people who are not fit to operate a lawn mower in charge of a jet with 400 people on it.
Maybe / maybe not relevant to proceedings but best post here.

World's best practice Framer, world's best...
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Old 9th Aug 2016, 11:40
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hi

I ‘ve a simple and clear question for qualified pilots on the triple 7

This concerns only the 777:
AP Off
AThr speed On / FD On
on short final approach, with a tailwind gradient of 10 knots for example, don't you think it would be better if auto-throttle keep managing the thrust after pulled them to idle -a few seconds earlier- to absorb the speed suddenly taken, caused by the 10 kts (tail wind)

Do you not think it would be better to have a similar management of the speed as is the case for the 737 or the A320/330/340/380
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Old 9th Aug 2016, 11:44
  #692 (permalink)  
 
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Volume:

However, If you do not have time to figure out the best speed, pulling up to the stick shaker is not totally off.
That's what i meant

The speed of steepest climb is related to engine power, the stall speed is not.
But the stick shaker limits you with stall, everything above gives you margin

Wirbelsturm:

Throw a stick shaker in there and your workload has gone through the roof
No, you didn't get the idea: BECAUSE of the suggested "Pull-Up", the pilot would EXPECT a stick shaker as limit. He will NOT be surprised.

What i would describe as the beauty of such a procedure is, that there is no mode to be achieved, chased and checked or misinterpreted, only manual max thrust, manual wings level and pitch up and as limit the shaker.
It seems to me the most simple and straight forward action for the first few seconds.

The astronautical and sublime automation operator can be displayed once safe ....
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Old 9th Aug 2016, 11:54
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Posted in the ME section:

Images Of The Emirates Plane That Burst Into Flames In Dubai, Photo Gallery

Shows the large nose gear doors open.
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Old 9th Aug 2016, 12:03
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A Go-Around, whether mandated by ATC or due to approach instability, deep landing or a bounce is not, nor should it be considered an emergency manoeuvre! It is something we are all trained to do and should all be briefing before the instigation of the descent checklist. It comes under the Non Normals and that's it.

There is no reason to pull to the PFI's and the stick shaker. In fact, in this case if the evidence really does point towards TOGA mode not being engaged then pulling to the stick shaker would have exacerbated the situation! Especially on a 300 series where a baulked landing with a rapid pull up could well puncture the tail!

Add into the mix of pulling up to such high levels of climb then you have a greater possibility of busting your go-around climb limits particularly when they are set low, such as 2000' due to controlled airspace above. Remember the MAP is a mandated 'procedure'.

In the event where situational awareness has degraded to such a point that you are unaware of terrain around you and suddenly get an unannounced EPGWS pull up warning then yes, absolutely correct to apply max thrust, dump the speed brake and pull to the PFI's. A normal Go-Around manoeuvre, in controlled airspace above an airfield? Not necessary IMHO.

Last edited by Wirbelsturm; 9th Aug 2016 at 12:15. Reason: Spellunk and grammer!!! Doh!
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Old 9th Aug 2016, 12:24
  #695 (permalink)  
 
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Originally Posted by Glofish
were what brought the three MD11 down and now a -300. All of them seemingly tried the procedure with holding actual attitude and then trying to go around .....
No, in at least one MD-11 prang (Narita), there were gross nose-down movements which resulted in the prang. Nothing like "holding the attitude" as you suggest. I wager that had the 521 crew pulled up to the stick shaker they'd all be dead.
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Old 9th Aug 2016, 12:30
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AFAIK the reason behind the MD11 crash was that the aerodynamic authority of the tail plane to control pitch is severely reduced at below recommended landing speeds and post any bounce (where the speed might have reduced below Vapp) the SOP was a full power go-around not an attempt to recover the landing.

Never flown the MD-11 so perfectly happy to be corrected.
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Old 9th Aug 2016, 12:56
  #697 (permalink)  
 
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The Jetstar flight in Melbourne referred to was the result of attempting a TOGA tap (pushing the thrust levers to TOGA momentarily then pulling them back to the climb detent to prevent overspeeding from too much thrust). They didn't actually hit TOGA and their company procedure at the time was to check for positive rate and call gear up before checking the FMA. As a result the aircraft was still in Land Mode. The 777 is quite different in that TOGA commands a maximum of 2000' per minute so no issues with too much power.
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Old 9th Aug 2016, 13:08
  #698 (permalink)  
 
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AFAIK the reason behind the MD11 crash was that the aerodynamic authority of the tail plane to control pitch is severely reduced at below recommended landing speeds and post any bounce (where the speed might have reduced below Vapp) the SOP was a full power go-around not an attempt to recover the landing.
Watch the video on Youtube. Had they done what you suggest, they would have been OK.
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Old 9th Aug 2016, 13:31
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You only pull up to the PLIs (stick shaker) if ground contact is still imminent after the initial pull up to 20 degrees. The only time you wouldn't achieve 20 degrees is at very low speed - if you've got a low speed event and GPWS then you really have screwed up. A pull up manoeuver from a baulked landing could result in a tail scrape, then massive energy and ROC which would likely bust the MAP altitude. It's not necessary and would be innapropriate.
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Old 9th Aug 2016, 13:50
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the SOP was a full power go-around not an attempt to recover the landing.
Never flown the MD-11 so perfectly happy to be corrected.
Actually, it was a full power GA with initially no conf change ....... which comes pretty close to a ...... initial pull up manoeuvre.

Anyway, it seems that my suggestion is a bad idea.

By the way, i have flown and nicely survived both the Maddog and the Rotating Rubbish -300 and with that experience in my backpack, guess what i would most probably do if trapped in such a situation ....
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