“Set standard”

[Busdriver01]

When departing under NADP1, in an A320, I was told not to set standard until reaching acceleration altitude. This often means reading back “climb FLIGHT LEVEL xxx” and then setting xx,000 and reading “xx,000 blue”, waiting until Acc. Alt to then set standard. Recently I had someone say that it doesn’t matter if you set standard before Acc. alt.

Anyone know definitively, and / or have a reference?

[RUMBEAR]

FCOM says to set STD at transition altitude. Are you saying you want to set it early just so you can callout a FL display on the PFD?

What happens if ATC amend the climb instruction to level off below transition due traffic and you have STD already set ?

[EGPFlyer]

If you’ve pre set your ACC Alt to say 3000’ then setting STD early will mean that the aircraft will now accelerate at FL030 which will be early or late depending on the QNH (unless of course it is 1013)

[Airmann]

FCOM says to set STD at transition altitude. Are you saying you want to set it early just so you can callout a FL display on the PFD?

What happens if ATC amend the climb instruction to level off below transition due traffic and you have STD already set ?

There is a school of thought that one should set QNH during descent as soon as one is given an altitude not at transition. A number of airlines follow this procedure.

[sonicbum]

When departing under NADP1, in an A320, I was told not to set standard until reaching acceleration altitude. This often means reading back “climb FLIGHT LEVEL xxx” and then setting xx,000 and reading “xx,000 blue”, waiting until Acc. Alt to then set standard. Recently I had someone say that it doesn’t matter if you set standard before Acc. alt.

Anyone know definitively, and / or have a reference?



Set standard when passing transition altitude. Imagine You are departing passing 2000 ft the ATC says "Climb FL180" (no constraints) You will set 18000 ft and call "18000" blue. When passing the TA 18000 will become FL180. Now if You find some weirdo who says "Oh but ATC said to climb FL180 and the PFD says 18000" tell him there is no need to panic, to keep on breathing, and when passing TA You will call for set standard.

[TheEdge]

Set standard when passing transition altitude. Imagine You are departing passing 2000 ft the ATC says "Climb FL180" (no constraints) You will set 18000 ft and call "18000" blue. When passing the TA 18000 will become FL180. Now if You find some weirdo who says "Oh but ATC said to climb FL180 and the PFD says 18000" tell him there is no need to panic, to keep on breathing, and when passing TA You will call for set standard.

CORRRRECT !!

[Max Angle]

If you’ve pre set your ACC Alt to say 3000’ then setting STD early will mean that the aircraft will now accelerate at FL030 which will be early or late depending on the QNH (unless of course it is 1013)
Not true, below the transition alt. entered in the perf. page the FMGS will reference altitude regardless of what is set in the baro ref. window. You can set STD whenever you like, as long as SRS is still engaged (ie. you haven't pulled open climb) the aircraft will accelerate at the correct time.

[akindofmagic]

Set standard when passing transition altitude

Or you could follow whatever the company SOP says, which in every airline I've worked for has been to set STD as soon as cleared to a FL.

[sonicbum]

Or you could follow whatever the company SOP says, which in every airline I've worked for has been to set STD as soon as cleared to a FL.

Of course, it goes without saying.

[TheAirMission]

I am assuming the reason why this question is asked is because of the relation Setting STD has to the FMA's on the PFD. To state the obvious when flying NAPD you remain in MAN FLX SRS until you have climbed through the NAPD1 altitude you have selected in the Perf page of the FMGC.

There will be some cases with a low QNH that if you were to Set STD whilst still in the NAPD 1 phase, thus climbing via SRS, that setting Standard would cause the aircraft to go from an altitude of 2,700 to FL30 straight away, which is only a QNH change of roughly 10 hPA.

If you selected 3,000 as your ACC altitude in the Perf Page to comply with NAPD 1 then by setting STD, in this case, you will have trigged the aircraft to enter CLIMB mode earlier slightly early, and thus not completing NAPD1, beginning the reduction in nose attitude and the increase in speed.

[sonicbum]

Talking about TA : "The paragraph 1.1.2.1.3 PANS-OPS, Aircraft Operations, Volume I, states that the height above the aerodrome of the transition altitude shall be as low as possible but normally not less than 900 m (3000ft)."
Does anybody have any reference of airports with TAs lower than 3000 ft AGL ? I can't seem to recall any.

[Check Airman]

Talking about TA : "The paragraph 1.1.2.1.3 PANS-OPS, Aircraft Operations, Volume I, states that the height above the aerodrome of the transition altitude shall be as low as possible but normally not less than 900 m (3000ft)."
Does anybody have any reference of airports with TAs lower than 3000 ft AGL ? I can't seem to recall any.

Learn something new every day. I wonder what the logic is. 3000ft is pretty low, and usually quite busy.

[sonicbum]

Learn something new every day. I wonder what the logic is. 3000ft is pretty low, and usually quite busy.

Having everybody flying Flight Levels ensure the proper vertical separation without the need to constantly update the local QNH on the altimeter. AFAIK there is a project for a common TA in Europe like in the US but I don't know at what stage the project is.

[giggitygiggity]

Don't forget practicality and reality. In the UK, for example, the TA is usually around 6000ft. If you've been cleared (passing 2000ft) to FL80, why wait to set STD? Is it more likely that ATC will suddenly re-clear you to A6000ft, or is it more likely that you'd forget to do it (distraction, whatever) and never make it to FL80. If ATC re-clear you lower, that is their mistake and they should reasonably expect you to take a few seconds (reasonably more than a few) to reconfigure the FCU for the new clearance.

WRT low transition altitudes, going into AMS, you will get cleared down to FL45 and maybe even lower. It's no big deal, you just fly it. On a procedural arrival/approach, more attention must be paid to the TA and it's significance should make up part of your brief, other than that, it isn't a big issue.

[Check Airman]

Thanks sonicbum.

I must be missing something though. Why not just use the tools available? The altimeter setting will flash when you get to TA/TL. If the perf page is properly set up, why go through the mental gymnastics that some companies impose? Set your altimeter when passing TA/TL, and if you forget, the system will remind you.

Sounds simple enough. What am I missing here?

[sonicbum]

Thanks sonicbum.

I must be missing something though. Why not just use the tools available? The altimeter setting will flash when you get to TA/TL. If the perf page is properly set up, why go through the mental gymnastics that some companies impose? Set your altimeter when passing TA/TL, and if you forget, the system will remind you.

Sounds simple enoug . What am I missing here?

Agree with You. One of our level bust mitigation strategies is for the PM to call “transition altitude” when passing the charted TA and the PF replies SET STANDARD. That proved to be quite helpful in situations where the TA was not properly set in the PERF page and was missed by the crew during the briefing. For descent we directly set the QNH when cleared to an altitude. Anyway I would not be against setting STD in climb directly when cleared to a FL if that was due to be a SOP change as I believe it does make sense to reduce the crew workload.

[TopBunk]

Check Airman

Set your altimeter when passing TA/TL, and if you forget, the system will remind you.

Sounds simple enough. What am I missing here?

Sure, that's an option - for those aircraft with that feature, but not all have it and you have to cater for everyone, surely?

I go along with my (ex)operator and agree with the philosophy of changing setting when first cleared to a FL/Altitude when climbing/descending.

In 99+% of occasions the clearance will not change, so to change when cleared makes sense and to deal with the 1% as the exception.

[Max Angle]

If you selected 3,000 as your ACC altitude in the Perf Page to comply with NAPD 1 then by setting STD, in this case, you will have trigged the aircraft to enter CLIMB mode earlier slightly early, and thus not completing NAPD1, beginning the reduction in nose attitude and the increase in speed. As I said in the post above you will not trigger climb mode by setting STD before the ACC altitude, the FMGS will reference QNH altitude below the TA that has been entered in the take-off perf. page.

[Check Airman]

Check Airman



Sure, that's an option - for those aircraft with that feature, but not all have it and you have to cater for everyone, surely?

I go along with my (ex)operator and agree with the philosophy of changing setting when first cleared to a FL/Altitude when climbing/descending.

In 99+% of occasions the clearance will not change, so to change when cleared makes sense and to deal with the 1% as the exception.

The OP asked about the A320, so I figured it was safe to make that assumption. In any event, you're right. Do current generation Boeings (apart from the 767) not have a feature that prompts you to change altimeter settings?

[swh]

]Do current generation Boeings (apart from the 767) not have a feature that prompts you to change altimeter settings?

The FO usually, that is if they are not to busy on tinder, Whatsapp, or Instagram

[MD83FO]

I treat the transition altitude and and thrust reduction altitude just like i used to on electro mechanical aircraft, i memorize it.
the children of magenta approach is to wait for the PFD to flash, for me thats to late.
they always end up reducing thrust at 1500’ instead instead of 1000’ takes them 500’ to reduce thrust.
On departure there should be awareness of TA which typically reflects the highest grid mora within that state.

[Yaw String]

Thread creep I know but,IMHO,Worth thinking about flap problem whilst cleaning up.
Sure,you can't account for every problem whilst operating the aircraft in every phase of flight.However,when things start to go wrong,and you are no longer going to climb to that FL,I like to have a setting that agrees with where I am..
One less thing to cock up!
My previous airline SOP stated that if cleared to FL in predeparture clearance,to not set STD until Flaps retracted, for that very reason.
However,as soon as we were cleared to FL in the air,they still seemed to set STD,regardless of where the flaps were.

Same in descent,states side..FL340, cleared to 16,000..Perfectly legal to set QNH ,but how often is the descent clearance amended,and how tired are we in that descent if it's the end of a transatlantic flight.

MD83FO,I'm with you..

[sierra_mike]

TA which typically reflects the highest grid mora within that state

not necessarily the case in EASA land

[MD83FO]

not necessarily the case in EASA land
I’ll take note SM

[ScepticalOptomist]

Our SOP is to set the altimeter setting passing the transition level. Very simple. Surprised at some of the SOPs being mentioned - just adds complexity to a very simple concept.

[oggers]

Same in descent,states side..FL340, cleared to 16,000..Perfectly legal to set QNH ,but how often is the descent clearance amended,and how tired are we in that descent if it's the end of a transatlantic flight.

AIM and PANSOPS both stipulate that you change altimeter setting at the TA in the climb and the TL in the descent. The PANSOPS exception is that QNH may be set above the TL when cleared for approach and descent has begun. Eurocontrol say:

ICAO PANS-OPS1 requires that the altimeter pressure setting should be changed to the new reference when crossing the transition altitude/level.
7.2. Some national authorities stipulate that, when an aircraft has been cleared to climb from an altitude to a flight level, vertical position will be reported in terms of flight level unless intermediate altitude reports have been specifically requested by ATC. Similarly when a pilot is descending from a flight level to an altitude the pilot will change to the aerodrome QNH unless further flight level vacating reports have been requested by ATC, in which case the QNH will be set following the final flight level vacating report. https://www.skybrary.aero/bookshelf/books/142.pdf (https://www.skybrary.aero/bookshelf/books/142.pdf)

[Busdriver01]

As I said in the post above you will not trigger climb mode by setting STD before the ACC altitude, the FMGS will reference QNH altitude below the TA that has been entered in the take-off perf. page.

This was the question I was actually asking! How does it know what the QNH altitude is? Does it go off what’s backset in the baro ref window, if you’ve already set standard? Because we don’t enter QNH anywhere on the MCDU before departure...

[A320ECAM]

Our SOP is plain and simple.

Climbing and 1000ft below transition, we announce "1000 to Standard".
Descending and 1000ft below transition, we announce "1000 to Standard".

Set standard/altimeter setting when passing the transition altitude.
In US, of course it's 18000ft.

The announcements gives us a bit of added situational awareness.

[8che]

So your level bust mitigation strategy is to wait until transition before setting standard ??

How does that work on a light weight aircraft on a low QNH day when you are cleared to the first flight level (1000ft above TA). Wait for transition and wait for the ATC report that’s filed when you press STD and see you are already above the cleared level !

Come on guys TEM. Good luck in places like Amsterdam.

[sierra_mike]

How does that work on a light weight aircraft on a low QNH day when you are cleared to the first flight level (1000ft above TA). Wait for transition and wait for the ATC report that’s filed when you press STD and see you are already above the cleared level !

TL is derived from TA (which is constant for most of the places). TL is the lowest FL you will get from ATC (in terms of units FL with no other factors considered here). this calculation is to assure that the case you described is not an issue respectively separation between aircraft flying in TA and TL is assured. e.g. you have a TA of 10000ft, 1000ft buffer layer and a local QNH of 990. your TL will be FL120. if you switch settings at TA your altimeter will indicate ca. 10600ft at that moment. 1400ft to go to FL120 which is the lowest FL ATC can clear you (again in terms of unit FL no other factors considered here...).
would it be a clever idea to reduce your vertical speed before switching in that example...maybe yes :E

[Max Angle]

How does it know what the QNH altitude is? Does it go off what’s backset in the baro ref window,
Exactly that, yes.

[Check Airman]

So your level bust mitigation strategy is to wait until transition before setting standard ??

How does that work on a light weight aircraft on a low QNH day when you are cleared to the first flight level (1000ft above TA). Wait for transition and wait for the ATC report that’s filed when you press STD and see you are already above the cleared level !

Come on guys TEM. Good luck in places like Amsterdam.
Yes it is. In Europe and some other parts of the world, TA can vary, and is quite low. I hesitate to say that in the US, our system is better, but it's certainly simpler, and thus less prone to error.

I've heard talk about simplifying it to a single level for years now. What could possibly be so difficult? Look at the highest terrain in the region, and set it a few thousand feet above that.

[FlightDetent]

I hesitate to say that in the US, our system is better, but it's certainly simpler, and thus less prone to error. And thus, better it is. :ok:

[hans brinker]

Yes it is. In Europe and some other parts of the world, TA can vary, and is quite low. I hesitate to say that in the US, our system is better, but it's certainly simpler, and thus less prone to error.

I've heard talk about simplifying it to a single level for years now. What could possibly be so difficult? Look at the highest terrain in the region, and set it a few thousand feet above that.

Yeah, flew for a few years in turboprops without any RNAV in Europe, was always fun flying low between Belfast, Isle-of-man and Liverpool , trying to figure out when you went from 4.000ft to FL040....

I know you have to set local QNH the for lower level flights in the USA, but the differences between area altimeter settings are most often a lot smaller than between QNH and QNE.

[FlyingStone]

I've heard talk about simplifying it to a single level for years now. What could possibly be so difficult?

We can't even convince ATC to use English language only for safety reasons in many places, including airports with 400k+ movements a year.

And you think getting a unified TA would be easy?

[sonicbum]

We can't even convince ATC to use English language only for safety reasons in many places, including airports with 400k+ movements a year.

And you think getting a unified TA would be easy?

I guess not, but who knows...

Towards a Common Transition Altitude (https://www.eurocontrol.int/sites/default/files/field_tabs/content/documents/nm/airspace/airspace-atmprocedures-flight-deck-perspective.pdf)