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Low level Go around A320

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Low level Go around A320

Old 14th Feb 2018, 14:33
  #41 (permalink)  
 
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The FCTM you quoted also appeared in Safety first before. It was to assuage the uncertainty felt when some times at heavy weight take off a fleeting over speed warning may appear. To say it's OK. But airbus doesn't tell you to reduce thrust to avoid it. They are certainly smart enough to do that. In case of GA Normal procedure is to leave the thrust levers in TOGA till ACC ALT or ALT* In our discussion we have already put it in CLB that so there is simply no question of over speed. For a WT of 64T when you set TOGA your speed will be about 140kt with flap 3 till ALT*. The F speed is round the corner so at ALT* check F speed and select flap1(not two as you said). And that's it. The VFE for flap 3 is 185 more than 35 kts away. And slats have same position for 2 and 3 so as the flaps move to 2 actual VFE becomes 200 and later at 1+F to 215kt. The only time problem comes is when at ALT* the PF goes in a stupor and starts thinking what to do. Even then if thrust levers are in climb it will maintain VFE. I have taught this dozens and dozens of times without problem. Now think about unnecessary intervention of reducing thrust. First is how much. Some one may close the thrust levers disconnecting ATHR. May then drop speed and trigger alpha floor or forget to engage ATHR and over speed. A pilot who forgets to select flaps one can forget anything. And why all this when the ATHR is programmed to maintain VFE and VLS irrespective of the target speed at either end. The adage "If it ain't broke don't fix it" is very true in airbus.
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Old 15th Feb 2018, 01:29
  #42 (permalink)  
 
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Originally Posted by Goldenrivett
Reading many of the above comments regarding the reluctance to even consider taking manual thrust control if the acceleration looks "too dynamic" - then I think the FAA are right to be concerned.
This isn't a matter of over confidence in automation nor erosion of manual flying skills; I have and will continue to take manual control, if it's what's necessary. It's not in this case. There isn't anything abnormal in what we are discussing, so why do something abnormal which, as vilas has described, could land you in more trouble?

BTW, if acceleration is "too dynamic", why not pull the speed and accelerate at your own pace? It would certainly be less of a handful than taking manual control (seldom done) in a go around (also seldom done) with a close level off altitude (also seldom). It's not required, but if it's a concern, it seems way easier to me...

As vilas pointed out, if it ain't broken don't fix it.
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Old 15th Feb 2018, 03:11
  #43 (permalink)  
 
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Originally Posted by vilas
pineteam
Quite a few things are strange. GA ordered by PM (may be a checker). But no GA flaps call by PF, no FMA read out by PF. FMA called only by PM, ATHR Blue was missed, +ve CLB by PF not PM, LVR CLB not called just executed and again ATHR active missed. Left side guy, the PF is just following orders then why is he on left? Not very impressive I am afraid.
Actually I think they're doing an excellent job, and the quick judgement of the guy on the back seat is not too impressive either.
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Old 17th Feb 2018, 08:56
  #44 (permalink)  
 
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Escape Path

Agreed.

Practicing manual flying skills, at an appropriate time, is certainly important.

Mismanaging automation during a go around (something a narrow body crew does about once per year https://www.bea.aero/etudes/asaga/asaga.study.pdf) is not an appropriate reason to exercise manual flying skills.

Of course if the PIC believes that is the only option to ensure aircraft control he or she should take overly manually. Then once at the gate with the parking checklist complete the Captain can initiate a conversation of how two qualified pilots so mismanaged the automation during a go around that the only way to ensure aircraft safety was to take over manually.

Unfortunately, as several accidents and incidents during go around show, that conversation between the pilots didn’t take place at the gate or it didn’t take place at all.
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Old 17th Feb 2018, 15:25
  #45 (permalink)  
 
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somatogravic illusions

Hi Escape Path,
BTW, if acceleration is "too dynamic", why not pull the speed and accelerate at your own pace?
Agreed. See my post #17.
"There are two options.
1) Pull speed and control the rate of acceleration.
2) Reduce thrust manually to a sensible setting."

CaptainMongo. Thanks for the link. It makes very interesting reading.
From Page 44:
"The main difficulties reported by the pilots surveyed are:…
A reduction in their capacity to cope with the situation, resulting from the momentarily excessive workload induced by the speed at which the situation changes.
The problems associated with managing a thrust considered by the pilots to be excessive, since it causes very high levels of acceleration and/or vertical speed.
The rapid changes in configuration (flaps and landing gear), aggravated by the need to make new manual inputs (FCU/FCP), to check them (FMA, PFD), or even to engage certain automatic systems (FD, AP, A/THR).
The management of the automatic systems, under time pressures, when the goaround does not adhere closely to the intended procedure. In these cases, the automatic systems may no longer be of assistance to the pilot.
The breakdown of coordinated actions or teamwork in the cockpit.
The obligation, on certain aircraft, to select full thrust: Which may be excessive, when the stabilisation altitude is too close to the altitude at which the decision to go around was made; ....
Which induced disruptions relating to somatogravic illusions."

Present simulators don't realistically simulate the sense of acceleration you will feel in real life when you perform a light weight GA with TOGA thrust and GA attitude of 17 degrees or so. (due to constraints of the simulator leg geometry). Some crews are taken by surprise and suffer from somatogravic illusion.

Page140.
"Consequently, the BEA completes this recommendation in the context of this study and recommends that:  ICAO ensure that manufacturers of simulators in cooperation with aircraft manufacturers improve simulator fidelity with respect to the phenomena of somatogravic illusions, especially during go-arounds. [Recommendation FRAN-2013-043]"

Page 121:
"Specifically, in case of a rapid increase in speed, they did not realise that it was better to reduce thrust manually, rather than to try to « understand ». "
Meanwhile I'll be ready to simply reduce thrust as necessary.

Last edited by Goldenrivett; 18th Feb 2018 at 15:38. Reason: format
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Old 17th Feb 2018, 23:38
  #46 (permalink)  
 
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Be ready but retract flaps first please.
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Old 18th Feb 2018, 00:33
  #47 (permalink)  
 
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A go-around as mentioned in the original post is a dynamic situation where flying, as always, is the priority. Retracting the flaps needs its part of communication that is not necessarily immediately affordable, therefore reducing thrust may be the logical option for the PF to settle things down and give some time for the proper communication to take place in order to further retract the flaps.
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Old 20th Feb 2018, 08:51
  #48 (permalink)  
 
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I’m 100% with Vilas on this one. Keep it simple: Follow Airbus Recommendations: Simply retract the flaps on schedule or if PM is out of the Loop, simply pull the speed in due time.

I really like to fly raw data and manual thrust, but I think using manual thrust during a go around on a well designed Airbus for the reasons mentionned above is definitely not required.
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Old 25th Feb 2018, 19:40
  #49 (permalink)  
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Originally Posted by Goldenrivett
On previous aircraft types the manufacturer fitted a reduced level of TOGA power and the easy ability to control the applied thrust - but it's not quite so easy on Airbus.
Actually the A350 has a - very useful - “SOFT GO-Around” mode.
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