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A320 Why do lot of pilots start chrono while starting engines?

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A320 Why do lot of pilots start chrono while starting engines?

Old 12th Apr 2016, 23:29
  #41 (permalink)  
 
Join Date: Sep 2003
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ENG MSTR SW = LP and HP Valves.

Partial Credit 👍

I don't know. I personally don't think using the FIRE P/B in that scenario is a poor decision if the PIC felt it was warranted. It's a judgement call.

Yes yes, I can hear the procedural police rolling over in their graves.....

However, if using the PIC judgement, it is safe, critical, going to kill me or someone else thought framework, I wouldn't be so quick to say "FCOM says this etc etc".

Last edited by Bula; 12th Apr 2016 at 23:40.
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Old 13th Apr 2016, 00:21
  #42 (permalink)  
 
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Thanks for the partial credit Bula but as with all things Airbus its not as straight forward as it appears. The HP valve is opened by FADEC during an automatic start and when certain conditions are met during a manual start one of which is the position of the eng master. During shutdown its the position of the LP valve that determines whether the fuel continues downstream. If it is closed then the engine will eventually shutdown which is why Airbus only give you the position of the LP valve on the schematics.

I totally agree with your last statement but I am aware of more people that have come unstuck operating outside of FCOM than operating inside FCOM.
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Old 13th Apr 2016, 00:37
  #43 (permalink)  
 
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Don't forget when selected to the off position, it commands both HP and LP valves outside of FADEC Partial credit.

Last edited by Bula; 13th Apr 2016 at 00:58.
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Old 13th Apr 2016, 03:34
  #44 (permalink)  
 
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it commands both HP and LP valves outside of FADEC
But its the LP valve that will determine if the engine shuts down or not, no fuel no noise. If the HP valve has failed either open or closed then you get an ECAM warning and its a call to engineering regardless.
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Old 13th Apr 2016, 03:53
  #45 (permalink)  
 
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Only if it is a HP failure in the open position. You can have an LP failure in the open position and the engine shutdown perfectly if the HP valve closes.

Both have ECAMS.

ENG LP VALVE FAULT

ENG FUEL VALVE FAULT. (This one for the HP)


Anyways, that's enough. Goodluck.

Last edited by Bula; 13th Apr 2016 at 04:14.
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Old 13th Apr 2016, 04:28
  #46 (permalink)  
 
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Before you go are you referring to CFM or IAE engines? According to DSC-70-95 p32/42 ENG 1(2) FUEL VALVE Fault states that the HP fuel valve failed closed,or failed open on an IAE engine.

There is no ECAM for the LP VALVE on an IAE equipped Airbus, thats why they have the Sup Proc!
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Old 13th Apr 2016, 04:39
  #47 (permalink)  
 
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IAE...though the LP ECAM only works if the valve is commanded closed and it stays open. Depending on the failure caseyou may or may not have it appear in the above scenario. It relies on a position disagree.

DSC-28-30


Don't you hate hanging around airports for hours and hours ... Right enough prune 🙈
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Old 13th Apr 2016, 12:54
  #48 (permalink)  
 
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I have seen a lot of pilots start chrono while starting the engine in A320.

It is not mentioned in the SOP anywhere and I couldn't find its utility.

Any good reason to do that?

Isn't situational awareness a good enough reason ?

Now let me ask some questions.

Does it cause you or anyone else any discomfort ?
is it likely to cause injury ?
Is it dangerous ?
Does it waste fuel ?
Does it waste electrical power to operate ?
Does it significantly reduce the service life of the component ?
Does it significantly increase unnecessary wear and tear ?
Does it affect the engine start or any other aircraft system in any way ?
Does it affect aircraft pushback ?
Does it cause damage ?
Does it waste time and delay departure ?
Does it increase workload ?
Does it waste energy ?
Does it affect anything that you or anyone else is doing ?
Does it affect any of the flight instruments on your side ?
Are you even aware the other pilot does it unless you look across ? (shouldn't you be monitoring the engine start and not small insignificant things that the other pilot is or is not doing ?)
Does it affect passenger comfort ?
Does it place increased risk and danger on the operation ?
Does Airbus specifically say not to do it ?
Is it beyond aircraft limits ?
Is it not what is was it designed for ? (to monitor timing as required)
Does it have any affect on anything else in the aircraft ?
Is the chrono being used usefully for anything else ?
Is the chrono timer specifically limited or designed for another particular function ?
Does the chrono distract anyone from doing their job ?
Is the chrono button difficult to operate ? Does it require special skill ?
Is it possible to make a dangerous error or increase any risk to safety whilst you operate it ? (even if you make an error)
Is it likely to increase any errors to be made ?
Is it not worth the risk (if there is any risk ?) to operate ?
Is the chrono timer out of normal view ?
Is the chrono button likely to get confused with another switch or button ? (that might cause something you don't want)
Is it a breach of the law or company policy ?
Is it noisy to operate ?
Does it affect the air temperature ?
Does it cost money to operate ?
Does it affect company revenue and profit ?
Does it modify the aircraft appearance ?
Does it affect the company image ?
Does it increase operating cost ?
Does it pollute the environment ?
Does it affect air traffic control ?
Does it affect cargo and baggage ?
Does it affect the toilet or galley ?
Is it offensive to anyone ?
Is it a security hazard ?
Is it politically incorrect, racist, sexist or discriminatory to operate ?


Then why does such a small insignificant thing really bother some people so much ?

Last edited by a_pilot; 13th Apr 2016 at 13:28.
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Old 13th Apr 2016, 16:21
  #49 (permalink)  
 
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Originally Posted by a_pilot View Post
Isn't situational awareness a good enough reason ?

Now let me ask some questions.

Does it cause you or anyone else any discomfort ?
is it likely to cause injury ?
Is it dangerous ?
Does it waste fuel ?
Does it waste electrical power to operate ?
Does it significantly reduce the service life of the component ?
Does it significantly increase unnecessary wear and tear ?
Does it affect the engine start or any other aircraft system in any way ?
Does it affect aircraft pushback ?
Does it cause damage ?
Does it waste time and delay departure ?
Does it increase workload ?
Does it waste energy ?
Does it affect anything that you or anyone else is doing ?
Does it affect any of the flight instruments on your side ?
Are you even aware the other pilot does it unless you look across ? (shouldn't you be monitoring the engine start and not small insignificant things that the other pilot is or is not doing ?)
Does it affect passenger comfort ?
Does it place increased risk and danger on the operation ?
Does Airbus specifically say not to do it ?
Is it beyond aircraft limits ?
Is it not what is was it designed for ? (to monitor timing as required)
Does it have any affect on anything else in the aircraft ?
Is the chrono being used usefully for anything else ?
Is the chrono timer specifically limited or designed for another particular function ?
Does the chrono distract anyone from doing their job ?
Is the chrono button difficult to operate ? Does it require special skill ?
Is it possible to make a dangerous error or increase any risk to safety whilst you operate it ? (even if you make an error)
Is it likely to increase any errors to be made ?
Is it not worth the risk (if there is any risk ?) to operate ?
Is the chrono timer out of normal view ?
Is the chrono button likely to get confused with another switch or button ? (that might cause something you don't want)
Is it a breach of the law or company policy ?
Is it noisy to operate ?
Does it affect the air temperature ?
Does it cost money to operate ?
Does it affect company revenue and profit ?
Does it modify the aircraft appearance ?
Does it affect the company image ?
Does it increase operating cost ?
Does it pollute the environment ?
Does it affect air traffic control ?
Does it affect cargo and baggage ?
Does it affect the toilet or galley ?
Is it offensive to anyone ?
Is it a security hazard ?
Is it politically incorrect, racist, sexist or discriminatory to operate ?


Then why does such a small insignificant thing really bother some people so much ?
It's a simple query to ascertain as to why some people might do it. It looks to me from reading the replies that the only person bothered about anything is you
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Old 13th Apr 2016, 16:36
  #50 (permalink)  

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Is it good for anything at all?
There, fixed it for you, I understand the exhaustion! Whilst writing such a lenghty post it is easy to get distracted and forget something, even the important stuff. That's exactly why somebody taught me to keep my SOP clean.

And it helps the new guys too, to have streamlined flows as simple as possible. That is before they get on the ball and are ready to prioritize tasks on their own.
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Old 13th Apr 2016, 18:46
  #51 (permalink)  
 
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Funny - on our IAE equipped Airbus we have an ECAM titled:

FUEL ENG 1(2) LP VALVE OPEN
Condition: An engine low pressure valve is open.

After a close reading, this ECAM would seem to indicate the engine low pressure valve was open when commanded closed.

Also the last time I checked, cycling the engine master to off closes both HP and LP fuel valves, among other things. Finally I would think it a miracle that an engine could remain running with a HP valve closed.
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Old 14th Apr 2016, 01:36
  #52 (permalink)  
 
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Make-work programs in the cockpit can possibly distract and only add minutia to the job. By creating non essential busy work items to your environment only adds to ones workload.

I do find it frustrating when some folks treat and train there habits and personnel technique as operational procedures.

The advent of automation technology should minimize button pushing, helping enhance your focus of the golden three.

With that said..... it is really no big deal and if pushing lots of buttons help you feel more like a pilot then go for it.

Last edited by jimmyg; 14th Apr 2016 at 03:58.
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Old 17th Apr 2016, 14:02
  #53 (permalink)  
 
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@a_pilot

This obviously bugs you, but a trifle overstated point, if I may say so!

Even while closely studying the engine instruments during a start for example, one can easily see and hear the other pilot clicking the chrono, or doing anything else. Most of us don't have tunnel vision, but keep an overall visual and audio 'picture' of what is going on around us.

But the reason why doing something non standard might be noteable is because anything outside SOP's at a critical moment is a possible cause for the other pilot to wonder if something is happening that they've not noticed - in which case it then might distract them away from the task at hand; "Why is he doing that? What did I miss?".

I thought we only had to time light up when doing manual starts? One cannot keep a cumulative record of starter useage with the (Airbus) chronos - they reset to zero every third click. I think the aircraft clock chrono can record accumulative time, but I have never seen anyone use that for engine starts.



PS, Why do some call it light off?, surely light up is more descriptive - the fuel has ignited?

Last edited by Uplinker; 17th Apr 2016 at 14:15.
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Old 18th Apr 2016, 01:17
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"Light Off" is old school DC9 MD11. I think it has just carried over, however used for completely different reasons. I believe they had lights to indicate ignition. These lights went out at some point.

It is important that one doesn't expect the automation to do everything. We really should be monitoring the automation, and interdicting when necessary in accordance with SOP/AFM. If you are sitting back fat dumb and happy, you are pulling yourself "out of the loop", and as stated, it is possible to exceed 2 minutes of starter operation on a normal start with an abort where high residual EGT is involved prior to start.

It is up to an individual pilot to assess an aircrafts limitation compliance. How you do it is technique and situational awareness. Starting the chrono is one such method.

To say it is distracting is a falsehood. If anything it should improve your situational awareness by reinforcing pertinent points of the start sequence by implementing interactive monitoring, rather than passive monitoring alone. Working with the automation to produce an outcome by following a sequence of events is far more effective as a precursor than just watching.

As pilots, whether it is an auto start sequence or autopilot, we know how important automation awareness is on the Airbus to avoid the "what's it doing now" scenario or automation surprise.
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Old 18th Apr 2016, 01:38
  #55 (permalink)  
 
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Well, it's about 330 with RR engines, but anyway, relevant to the topic. I saw the first unsuccessful start attempt lasted more than 3 min. After that according starter limitations there should be a cooling period of 30 min. Never mind - FADEC allowed the second attempt without any message.
This is the first reason I use stopwatch - to control starter limitation. The second - to keep the habit for manual start.
Another related note: there is no SOP to start timing on takeoff. We start it to control the takeoff thrust time limit. Not sure the aircraft would give any message in case of exceedance.
Another case, when limitations are not guarded by the aircraft. You can enter quite a wild ZFW and ZFCG, well above limitations with no warning message and get Gross Wieght again well above and again - no warning.
It's not perfect...

Last edited by Romasik; 18th Apr 2016 at 01:48.
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Old 18th Apr 2016, 10:42
  #56 (permalink)  
 
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Light Off" is old school DC9 MD11. I think it has just carried over, however used for completely different reasons. I believe they had lights to indicate ignition. These lights went out at some point.
Thanks
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