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tonker
26th Apr 2018, 10:37
Hi

Can anyone tell me if there is any regulatory information that demands that information on the CDU must reflect the SID?

ie Your first stop altitude is 4,000 feet hard altitude, and ATC clear you to 4,000 feet. Why not then delete the 4,000 feet hard altitude? Not an SOP or flying manual question, but a regulatory question. Is it written down somewhere by EASA CAA FAA etc

Thanks in advance

RAT 5
26th Apr 2018, 11:32
Question. Why would you? How does it improve the situation? It will reduce situational awareness in a critical phase. Regulatory? I doubt it.

BluSdUp
26th Apr 2018, 12:04
We almost never fly the Stars and Sid as published. A lot of direct to....
Why would Naa mikromanage such a thing??
Read what ICAO recommends , if anything.
As your question is SID specific I would only be concerned about MSA , airspace restricted altitudes etc.
On Stars I personalty delete altitude restrictions I know are not used to do CDA.
Plenty of places , RAT this gives you a higher and safer situational awareness. ( on Stars, Approaches)
PO
Your SOP should cover this. ?

sonicbum
26th Apr 2018, 12:13
Hi

Can anyone tell me if there is any regulatory information that demands that information on the CDU must reflect the SID?


Yes it does, You can find more info Here (https://www.icao.int/EURNAT/Other%20Meetings%20Seminars%20and%20Workshops/PBN%20and%20Associated%20PANS-OPS%20Provisions%20Workshops/PBN%20and%20Associated%20PANS-OPS%20Provisions%20Implementation%20Workshop%20Belarus/PBN%20and%20PANS%20OPS%20Imp%20Wkshp%20BLR%20PPT14.pdf?TSPD_ 101_R0=68533d9f9017eecd6eb96c7b6ae60e85e4J000000000000000014 612c5dffff00000000000000000000000000005ae1b3180082e687dc)

Doug E Style
26th Apr 2018, 12:14
If you fly an Airbus, leaving things as they are will give you a magenta reminder on the ND (if you have constraints selected).

RAT 5
26th Apr 2018, 12:18
RAT this gives you a higher and safer situational awareness.

If you mean deleting an FMC hard altitude "gives you............." you'll have to explain that. Or am I misunderstanding what you've written?

FlyingStone
26th Apr 2018, 12:18
The coded hard altitude in the FMC database is one of the safety layers keeping you away from a level bust on departure. Can't think of any good reason why you would want it gone.

sonicbum
26th Apr 2018, 12:25
Guys in PBN OPS You are not allowed to start changing and modifying stuff at your own convenience, there's loads of literature regarding that. Your FMC database is checked and approved by your operator following a specific protocol and it is not supposed to be modified every single sector.

edit* : unless you are specifically instructed to cancel speed and altitude restrictions from ATC.

BluSdUp
26th Apr 2018, 12:35
RAT 5
Thanks, I made no sense there,
Example , ILSz rwy 13 AGP the box has 5000 twice within a short distance. If deleting the first this will give ca 5800 and you are then on a higher profile. Safer!?

Not relevant I suppose as we are talking SID.

poldek77
26th Apr 2018, 12:42
Example , ILSz rwy 13 AGP the box has 5000 twice within a short distance. If deleting the first this will give ca 5800 and you are then on a higher profile. Safer!?

What if there is a crossing track with minimum altitude of 6000' ?

BluSdUp
26th Apr 2018, 12:55
There is not. You are cleared for the ILS at that point. The GS is at 5800 but has small ups and downs as there is hills reflecting the GS slightly.
But, Yes do not apply this anywhere!

RAT 5
26th Apr 2018, 14:08
Thanks Blu.

Pontius
26th Apr 2018, 14:18
edit* : unless you are specifically instructed to cancel speed and altitude restrictions from ATC.

Edited again: Or flying in somewhere like the UK or Japan when ATC clearance to higher automatically cancels the restriction.....unless re-stated.

Yes, I too wish they could come up with one version auto cancel or not auto cancel, I really don't care which one but just pick one and stop the individual differences :rolleyes:

Intruder
26th Apr 2018, 21:39
Can anyone tell me if there is any regulatory information that demands that information on the CDU must reflect the SID?
ie Your first stop altitude is 4,000 feet hard altitude, and ATC clear you to 4,000 feet. Why not then delete the 4,000 feet hard altitude? Not an SOP or flying manual question, but a regulatory question. Is it written down somewhere by EASA CAA FAA etcFirst, there is no regulation requiring a CDU. you can fly a VOR/DME-based SID using raw VOR and DME data if you like.

HOWEVER, if you are flying an RNAV SID, with authorization to do so in an OpSpec or LoA, you must follow the applicable regulations for the level of RNAV you are using. For example, if flying an RNAV1 or RNAV2 SID, you must use an autopilot or flight director. Either of those would be difficult to use without the correct information in the CDU. OTOH, you MIGHT be able to use the MCP in place of CDU altitude constraints, but why would you?

Icelanta
27th Apr 2018, 03:17
ATC clearance cancels out SID altitude restrictions in most countries .

pineteam
27th Apr 2018, 03:59
If you fly a RNAV SID/STAR. You can clear the altitude constraints or speed restrictions if ATC tells you no altitude/speed restrictions. The only thing you are not allowed to do in the FMS is to add manually a waypoint.

“Manual entry of SID/STAR waypoints is not permitted.”
From our SOPM.

sonicbum
27th Apr 2018, 14:18
FCOM is very clear, that clearing the SPD CST from the MCDU in NOT the recommneded procedure.

Are You aware of the fact that there are other aircrafts around the world other than Airbus and different company SOPs ?

PENKO
27th Apr 2018, 20:41
FCOM is very clear, that clearing the SPD CST from the MCDU in NOT the recommneded procedure. Selecting the desired speed on the FCU is.
Where does it state this? Please provide a reference.
All my FCOM mentions is that if a specific speed is required, use selected. Nothing against clearing unused speed constraints, i.e. 250 below 100 if you have already accelerated. Why fly around with incorrect predictions?

Either way I would not get too worked up about it. Surely you make many more alterations to the MCDU during climb and descent, like sequencing the flight plan when on vectors. That's much trickier than a simple deletion of a speed constraint. If you can't manage that..

aterpster
28th Apr 2018, 14:08
Question. Why would you? How does it improve the situation? It will reduce situational awareness in a critical phase. Regulatory? I doubt it.

Unless it is specified in an aviation authority approved operations document.

172_driver
28th Apr 2018, 15:48
This thread is about to turn into another SOP fist fight.

Delete them as you please, just don't bust the level off. Valid for any departure, whether out of LHR or anywhere else.

We've got no SOP in place that requires the hard altitudes in the FMC.

RAT 5
28th Apr 2018, 20:03
IMHO this is not an SOP fist fight.

Delete them as you please, just don't bust the level off.

IMHO it is more an airmanship and awareness tool issue. At times like this I always ask a relevant question, depending on the issue. In this case the FMC has a hard altitude in its data base for the SID. ATC clear you for the SID. You enter the altitude in MCP. Now, for the briefing you have a displayed confirmation between the FMC and MCP about the clearance. To delete the altitude in the FMC requires extra steps, effort, crew confirmation, (I'm sure you wouldn't do it on your own, would you).
The question is; how have you improved the situation by deleting the FMC Altitude? You haven't; but you've spent conscious effort & thought doing it. Why? There are some operators that depart in VNAV, or will use that mode after flaps up. VNAV will capture the FMC ALT. By removing it you are relying solely on MCP. We do so many things with belt & braces. Removes the braces, and if the belt is too lose, your trousers fall down.
I flew with a couple of operators who did have an SOP. If the SID cap was not associated with a WPT then it was not in the FMC data base. It was a requirement to enter the cap at a suitable WPT in the FMC, for the reasons stated above. IMHO seemed like a good idea.

Vessbot
28th Apr 2018, 21:50
Yeah, I see no advantage and every possible disadvantage for getting cleared to 4000 and deleting the 4000 from the FMS. This makes no sense, and I don't see why anybody would want to do that.

Tonker, are you sure you didn't mean to ask about, for example, getting cleared to 5000 and deleting the 4000?

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172_driver
28th Apr 2018, 22:14
My reasoning; If you keep/insert hard altitudes out of London then you better do it at all other ports as well. I know some operators do it. My current airline has no procedure/culture doing so. We're two pilots that go through the routing and stop altitude during the briefing. Has worked well so far and doesn't seem to cause any altitude deviations. Lastly the the FMC will only stop you if climbing in VNAV which many aren't doing approaching a low level off.

172_driver
28th Apr 2018, 23:22
I might just be slow, but I like to keep it clean and control my altitude in one place (that would be the MCP). What would happen if I am slowly climbing in V/S to 5000 ft enroute to a fix with a 4000 ft hard altitude. I forget to follow up pressing ALT INTV once, twice, three times.... Then cleared up high to FL170 and press VNAV? It will probably show an error message and disconnect VNAV? Just speculating through the grapevine.

PENKO
29th Apr 2018, 07:22
Direct To's REQUIRE an alteraton in the MCDU, a SPD change doesn't smart arse. That is what Airbus say the FCU is for.
Not surprisingly you are missing my point completely. As PF, I use the FCU. So why is the F/O clearing speeds from the MCDU without being asked to do so and without confirmation?

Sorry I forgot, F/O's run the Flight Deck these days.

May I kindly suggest yours is a problem of CRM, not SOP?

I have worked for an airline where deleting hard heights on the SID was SOP. Currently I operate without any hard guidance regarding these heights other than the mention that some specific countries like you adhere to these heights on descent even when cleared direct to a further waypoint.

So in practice in descent I clear useless hard heights, for example the irrelevant 4000 at MAY on approach into LGW when I very well know that this will ruin my mandatory continuous descent under radar vectors, but keep those that really matter. On the SID I keep all hard heights in as it heightens situational awareness and that's also what the SOP's imply. This seems to work out fine, but if your SOP's differ then that's absolutely fine as well. All that matters is the pay check at the end of the month.

sonicbum
29th Apr 2018, 11:08
Direct To's REQUIRE an alteraton in the MCDU, a SPD change doesn't smart arse.

That's what You call advocacy ! :p:p:p

Uplinker
29th Apr 2018, 12:55
Both Airbus and Boeing have climb and descent modes that will ignore pre-programmed altitude constraints : Open climb/descent or Level change*. (I don’t know about other types).

So why bother to remove them ? As others have said; making unnecessary changes to programming carries a significant TEM risk, and while most of us are perfectly capable of changing constraints - be they speeds or altitudes - one day you might accidentally remove a rather vital waypoint instead.

There seems little point if the system can be ‘told’ to ignore altitude constraints. Better to use those extra few brain cells to concentrate on SA and busy traffic than go heads down. If a descent constraint is irrelevant on the day, and would schedule a descent too early or too late, then, OK, delete it, but otherwise probably safer to leave it alone.

After all, unintentionally levelling at a published SID/STAR constraint that ATC have cancelled is arguably safer than accidentally removing a complete waypoint?


*After years on the Airbus, am brand new to the Boeing, so please correct me if I am wrong.

FullWings
29th Apr 2018, 15:55
What’s the worst that can happen if you leave a hard restriction in on departure that gets in your way later on? The a/c attempting to level off earlier than you might like which is easily rectified, no harm done. Especially if you keep the FMAs in your scan.

If you delete something that was or became relevant, you are increasing the possibilities of a) a level bust, b) a TCAS event and/or c) an Airprox or worse.

Looking at those two alternatives from a risk PoV, which would you rather have...?