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General EFIS and A320-specific questions

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General EFIS and A320-specific questions

Old 1st Oct 2020, 17:51
  #21 (permalink)  
 
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Originally Posted by FlyingStone View Post
Sticking to Mr. Boeing/Airbus SOP has a distinct disadvantage - it means the airline's SMS has nearly zero input into it, and the input it might have, will have an enormous latency between the line events and the implementation of the SOP change that seeks to eliminate similar events from occuring.

Manufacturers cannot predict every single operational environment in the world, and these will vary a lot between airlines - e.g. requency changes over Africa, where all frequencies have a single decimal number and occur once every hour pose less risk of dialing the wrong frequency, getting into PLOC and perhaps even getting intercepted than operating in Maastricht/Rhein area in EU, where you have 8.33 frequencies, and changes less than 5 mins apart.

Similarly, pointing to MCP/FCU might seem silly to somebody who operates in airspece, where you get five level changes in the entire flight, but it might - possibly - make a small bit of sense when you operate 4 or 6 sector days into London TMA, FRA, etc., where you often get 20 level changes on the way up and 20 on the way down.
It does not make any sense to point the altitude on the FCU ; Airbus callout is FL XXX blue (or magenta in case). Pointing the FCU is only half of the story and in case of an alt constraint lower than the FCU altitude it is actually misleading. What the airplane will do is only dictated by the FMA, all other data is almost useless.
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Old 1st Oct 2020, 18:04
  #22 (permalink)  
 
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There's a safer and simpler way. Inform the manufacturer about your proposed changes. Because apart from the design philosophy and software and hardware access the manufacture has a global customer reach and incidents. So if you want to change something in Argentina that may have been already done in Korea and ended in a screw up. Armed with FCOM, FCTM no one is in a position to make their own procedures. There's famous incident of Jetstar Australia and two other Airlines changing FMA call on GA to only after gear up. The captains stopped short of TOGA and waited for gear up to check the FMA. Copilot waited for positive climb to put gear up. The aircraft remained in approach and worst case it came down to 14feet before they pulled up. All returned to previous procedure. TOGA first FMA to confirm transition to GA then everything else.
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Old 1st Oct 2020, 21:33
  #23 (permalink)  
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Originally Posted by sonicbum View Post
It does not make any sense to point the altitude on the FCU ; Airbus callout is FL XXX blue (or magenta in case). Pointing the FCU is only half of the story and in case of an alt constraint lower than the FCU altitude it is actually misleading. What the airplane will do is only dictated by the FMA, all other data is almost useless.
The case with altitude constraints is the only case where I’ve seen the PFD not match the FCU (by design).

This situation is where I actually find it useful to point to the FCU. ATC clears you to 6000, and the FCU reflects that clearance limit, even though the PFD shows 12,100 in pink.
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Old 1st Oct 2020, 22:47
  #24 (permalink)  
 
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Originally Posted by Capt Pit Bull View Post
Can’t comment on the bus but on the boeing you can’t deduce the state of the modes by looking at the MCP!

You can see what is deselectable, that does’t give you the complete picture.

e.g.
in alt hold, the mcp button might NOT be illuminated.
an illuminated VORLOC button could be armed not engaged.
an Illuminated AP button isn’t necessarily engaged (e.g early part of intended 2 channel approach)

This is why you look at the FMA not the MCP

how the **** do people not understand this? Why is the question even being asked?

Shit training, that’s why.

this industry need to stoo cutting corners and pull its head out of its arse.

FFS. Somebody shoot me.
Relax pitbull, he is probably ( most likely) asking about the bus, reason for that his second question. And you wonder, why is that guy asking that? Maybe because he had a captain just like you in training that such kind of question would immediately rise his attention and not in a good way, could that be the reason?.. Maybe??? Just saying.
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Old 2nd Oct 2020, 06:50
  #25 (permalink)  
 
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Originally Posted by Check Airman View Post
The case with altitude constraints is the only case where I’ve seen the PFD not match the FCU (by design).

This situation is where I actually find it useful to point to the FCU. ATC clears you to 6000, and the FCU reflects that clearance limit, even though the PFD shows 12,100 in pink.
You mean magenta I guess.

Depends a lot on airlines SOPs then. We never set anything lower (higher) than the active constraints, I.e. cleared down to 6000 ft via STAR we set the different step down constraints on the FCU, but yes technically it is perfectly fine to just set your final altitude provided you are in DES or CLB all the time.
If your policy is the latter, then I see the point of your comment.
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Old 2nd Oct 2020, 06:58
  #26 (permalink)  
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Originally Posted by sonicbum View Post
You mean magenta I guess.

Depends a lot on airlines SOPs then. We never set anything lower (higher) than the active constraints, I.e. cleared down to 6000 ft via STAR we set the different step down constraints on the FCU, but yes technically it is perfectly fine to just set your final altitude provided you are in DES or CLB all the time.
If your policy is the latter, then I see the point of your comment.
yes. Magenta.

I have to ask. Why? Assuming you fly a Boeing/Airbus, what’s the benefit, and how do you handle soft constraints (eg 21,000-23,000)?
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Old 2nd Oct 2020, 09:00
  #27 (permalink)  
 
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Originally Posted by Check Airman View Post
Hi all,




1- we’re usually taught that when changing a value (not mode) on the FCU/MCP, to verify that the new value is reflected on the PFD, and not just the FCU. Has anyone ever seen a situation where the PFD and FCU values are different?
I had this just the other day. While Changing the BARO QNH setting with the selector on the FCU, the value in the FCU window didn’t change but the value on the PFD did (including a corresponding change in altitude indicated).

A basic Airbus principle is to look for the output rather than rely on the input. If you try to switch your kitchen light on you check that the bulb has illuminated rather than relying on the switch position alone.
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Old 2nd Oct 2020, 09:17
  #28 (permalink)  
 
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Originally Posted by Check Airman View Post
yes. Magenta.

I have to ask. Why? Assuming you fly a Boeing/Airbus, what’s the benefit, and how do you handle soft constraints (eg 21,000-23,000)?
As many operators, we also had a few level busts over the years, because of crew selecting the final cleared altitude on SID/STARS with constraints in the middle and for some reason getting out of CLB/DES and here you go, you get a level bust. We basically write down the final cleared altitude on PM MCDU (eg. descend via STAR 3000 ft) and select step by step the different altitudes on the STAR (5000 ft, 4000ft, etc..).

I am not a big fan of the above procedure, as we were discussing above “know your FMA at all times” should be the priority but as we know our business is driven by internal and external statistics.
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Old 2nd Oct 2020, 09:44
  #29 (permalink)  
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Originally Posted by Tail-take-off View Post
I had this just the other day. While Changing the BARO QNH setting with the selector on the FCU, the value in the FCU window didn’t change but the value on the PFD did (including a corresponding change in altitude indicated).
Interesting. How’d you fix it?
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Old 2nd Oct 2020, 09:54
  #30 (permalink)  
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Originally Posted by sonicbum View Post
As many operators, we also had a few level busts over the years, because of crew selecting the final cleared altitude on SID/STARS with constraints in the middle and for some reason getting out of CLB/DES and here you go, you get a level bust. We basically write down the final cleared altitude on PM MCDU (eg. descend via STAR 3000 ft) and select step by step the different altitudes on the STAR (5000 ft, 4000ft, etc..).
That would not be fun going into LAX on the Hollywood STAR. Just about every fix has a constraint, but it’s pretty simple. You set the FCU to 12,000 for the bottom of the star, then you set the FAF altitude when cleared for the approach at ~ FL200. Easy as pie (when it all works ). DES is a lovely thing.

Thanks for the insight though. There are as many ways to do it as there are operators.
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Old 2nd Oct 2020, 13:46
  #31 (permalink)  
 
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Originally Posted by Check Airman View Post
Interesting. How’d you fix it?
7 minute FCU reset of both channels (we were on the ground).
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Old 4th Oct 2020, 06:43
  #32 (permalink)  
 
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Originally Posted by sonicbum View Post
As many operators, we also had a few level busts over the years, because of crew selecting the final cleared altitude on SID/STARS with constraints in the middle and for some reason getting out of CLB/DES and here you go, you get a level bust. We basically write down the final cleared altitude on PM MCDU (eg. descend via STAR 3000 ft) and select step by step the different altitudes on the STAR (5000 ft, 4000ft, etc..).

I am not a big fan of the above procedure, as we were discussing above “know your FMA at all times” should be the priority but as we know our business is driven by internal and external statistics.
So what happens if the PM needs the MCDU for something else? I'm also curious if your company just ended up replacing constraint busts with final clearance limit busts. I guess not, particularly if you tend to get cleared lower before reaching the level.
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Old 5th Oct 2020, 05:44
  #33 (permalink)  
 
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I flew with a guy who failed his upgrade a few years ago and was hoping to be given another shot at it sometime in the future.

As we climbed out passing transition altitude, as with SOPs I said “Set Standard” and although he did the action, his side remained on the QNH. He then replied as with SOPs “Standard cross checked passing FL???” even though in front of him it was very clear he still had the QNH set.
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Old 5th Oct 2020, 06:29
  #34 (permalink)  
 
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Originally Posted by Check Airman View Post
Thanks for the feedback so far guys.

To be clear, I’m not talking about mode awareness on the FMA. I’m only talking about the actual numbers. Eg have you ever put 300 in the speed window and had anything but 300 get bugged on the PFD?
I’ve set 180° with the heading knob once and somehow the speed bug showed 180kts on the PFD😩😩 it’s worth checking.

On the E Jet, there are no lights or digits on the MCP/FCU. The only way to confirm you have set/selected anything is to check the PFD.
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Old 5th Oct 2020, 07:06
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Originally Posted by Roj approved View Post
I’ve set 180° with the heading knob once and somehow the speed bug showed 180kts on the PFD😩😩 it’s worth checking.
PFD.
And that’s why you turn the FCU and read the PFD.

Amen
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Old 5th Oct 2020, 08:20
  #36 (permalink)  
 
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Originally Posted by AerocatS2A View Post
So what happens if the PM needs the MCDU for something else? I'm also curious if your company just ended up replacing constraint busts with final clearance limit busts. I guess not, particularly if you tend to get cleared lower before reaching the level.
The PM will then use the MCDU as needed.

Apparently the fleet office is quite happy with the statistics of this SOP. There have been in the past events where the crew mainly changed from DES to V/S and that lead to the troubles. The mitigation strategy was to prohibit the use of V/S when descending/climbing "via" a STAR/SID and the use of step FCU altitude selections. My bet is that the latter will be removed soon as, again, it does not make sense if things are done properly from the beginning.
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Old 5th Oct 2020, 08:51
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Originally Posted by sonicbum View Post
The PM will then use the MCDU as needed.

Apparently the fleet office is quite happy with the statistics of this SOP. There have been in the past events where the crew mainly changed from DES to V/S and that lead to the troubles. The mitigation strategy was to prohibit the use of V/S when descending/climbing "via" a STAR/SID and the use of step FCU altitude selections. My bet is that the latter will be removed soon as, again, it does not make sense if things are done properly from the beginning.
It may have happened due to incomplete understanding of DES mode and constraint compliance. Easier to explain that than device more complicated solution.
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Old 5th Oct 2020, 09:17
  #38 (permalink)  

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If the vertical profile guidance before FAF/P was not such crap, perhaps people would be inclined to using the DES mode without intervening all the time?

But it is not.
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Old 5th Oct 2020, 09:25
  #39 (permalink)  
 
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Originally Posted by vilas View Post
It may have happened due to incomplete understanding of DES mode and constraint compliance. Easier to explain that than device more complicated solution.
Nah, people with over 10k hours on type, just trying to be smarter and doing it "better" than the system. Then a distraction comes in, and here you go.
Unfortunately from a trainer's point of view the solution is always the same : training !
From a Ops/safety point of view it's training AND something else to teach the remaining 99% of the pilots population not to be naughty.
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Old 5th Oct 2020, 14:26
  #40 (permalink)  
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Originally Posted by sonicbum View Post
The PM will then use the MCDU as needed.

Apparently the fleet office is quite happy with the statistics of this SOP. There have been in the past events where the crew mainly changed from DES to V/S and that lead to the troubles. The mitigation strategy was to prohibit the use of V/S when descending/climbing "via" a STAR/SID and the use of step FCU altitude selections. My bet is that the latter will be removed soon as, again, it does not make sense if things are done properly from the beginning.
Man. I sure hope nobody from my airline management is reading this. This is exactly the sort of stuff they come up with that leaves us wondering why we’re flying the thing like it’s a 707.
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