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dmiannay

How to Add ABOVE and BELOW Altitude Restriction

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I have searched far and wide and read through countless tutorials and can't find find instructions on how to add an ABOVE and BELOW altitude restriction on the FMC LEGS page.  I can easily add speed and altitude constraints for either an ABOVE or BELOW altitude restriction but can't break the code on adding the ABOVE and BELOW restriction.  I see them on many STARS (like the SADDE fix on the KLAX KEACH1 STAR). Can someone point me to a document or video somewhere that covers how to do this particular type of input?

 

Thanks!

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Above and Below? How can you be both? FL150 or ABOVE. FL150A, or FL150 or BELOW FLA150B, but I'm unsure how you could request someone to be "anything but FL150"

 

Edit: Ok looked up it, and you mean between FL130 and FL10000. Pick one, depending on how you're doing in flight. If your descent gives you easier on speed but its 130, go with 130, but if speed isnt an issue and you get down to 10000 without a problem, with 10000. Imagine two situation, one with huge tail one, one with huge head wind. Or, imagining ATC keep you high for longer, 130 is easier. Its all about what happens at the time

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Hehe... there are many fixes with restrictions like 10000A and 13000B which means you are legal to cross anywhere between 10000 and 13000.  Look at the LAX STAR I referenced above and you'll see several fixes with ABOVE and BELOW altitude restrictions.  They are actually quite common.  I just don't know how to enter one manually in the FMC.

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I have to admit, I didn't really know what you meant until I fired up Navigraph to have a look

 

REe3alk.jpg

 

isn't it based on the *previous* fix?

For KEACH1, if you're coming from VENTURA the restriction is 11000.

If you're coming from FILLMORE the restriction is between FL180 (TA) and 16000, then SYMON is between 15000 and 13000. 

 

I think the main thing is that you're at BAYST at 10000. Hopefully I've got that right?

 

I don't think you can set a below and above restriction. just make sure it's at 10000 at BAYST.

 

Kyle? :smile:

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I can easily add speed and altitude constraints for either an ABOVE or BELOW altitude restriction but can't break the code on adding the ABOVE and BELOW restriction.

Hi, Doug,

 

See PMDG-777-FCOM2.pdf p. 897.

 

It won't let me copy due to copy restrictions.

 

Hope this helps.

 

Mike

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In the CDU in the NGX you can easily set "at or above", "at or below", and "at or above and at or below" constraints. The entries might look like...

 

(speed)/10000A for at or above 10000ft at (fix)

 

(speed)/10000B for at or below 10000ft at (fix)

 

(speed)/10000A/13000B for the example on the chart at SADDE. The speed entry is done only if needed, if not, leave it out.

 

I would assume that this would work in the 777 as well.

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Hi, Doug,

 

See PMDG-777-FCOM2.pdf p. 897.

 

It won't let me copy due to copy restrictions.

 

Hope this helps.

 

Mike

 

Thanks, Mike. I completely missed that in the FCOM, but sadly I can't get it to work in the FMC for the SADDE waypoint.  There must be something simple I'm missing.  I enter 250/130B100A into the RH LSK next to SADDE an get INVALID ENTRY every time.

 

And thanks to you as well, Dave.  Unfortunately your suggestion does not work either.  I've tried numerous combinations.

 

Soldiering on...

I have to admit, I didn't really know what you meant until I fired up Navigraph to have a look

 

REe3alk.jpg

 

isn't it based on the *previous* fix?

For KEACH1, if you're coming from VENTURA the restriction is 11000.

If you're coming from FILLMORE the restriction is between FL180 (TA) and 16000, then SYMON is between 15000 and 13000. 

 

I think the main thing is that you're at BAYST at 10000. Hopefully I've got that right?

 

I don't think you can set a below and above restriction. just make sure it's at 10000 at BAYST.

 

Kyle? :smile:

Hey Neil,

 

Thanks for responding.  While being at 10000 at BAYST is clearly required, there are multiple reasons for having altitude restrictions at prior waypoints, some having to do with ATC flow control, etc.  I'm sure Kyle can illuminate us if he weighs in :)

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I enter 250/130B100A

Not at my FS computer, but maybe 13000B10000A since you are below the

transition altitude of 18000? Also, maybe you can't add a speed constraint although I can't

imagine why.

 

Mike

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I just don't know how to enter one manually in the FMC.

 

 

 


Kyle?

 

FCOMv2 11.31.19.

 

 

 


I enter 250/130B100A into the RH LSK next to SADDE an get INVALID ENTRY every time.

 

It's working for me. Are you doing anything else that might be interfering with this?

 

2015-6-19_19-14-50-713.jpg

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Thanks, Kyle.  I saw the proper procedure in the FCOM and understand that it is working for you.  I have a thought... if there was already a constraint on the LEGS page for SADDE (it was 250/10000A), will my new one overwrite it or do I have to delete the former before adding the new?

 

Update:  I just tried deleting the former constraint at SADDE and entered 250/130B100A into the RH LSK and got the INVALID ENTRY again.  I can't imagine what I could be doing to interfere.  I was simply cruising at FL380 along the routing and noticed the SADDE fix didn't have the correct restrictions, so was trying to fix it.  Perplexing.

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I was simply cruising at FL380 along the routing and noticed the SADDE fix didn't have the correct restrictions, so was trying to fix it.  Perplexing.

 

I know this isn't "fixing" anything, but I'm not sure where you got that chart, and why it's not correct. The KEACH has a 100A crossing (but not a between like your chart):

http://155.178.201.160/d-tpp/1506/00237KEACH.PDF

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I know this isn't "fixing" anything, but I'm not sure where you got that chart, and why it's not correct. The KEACH has a 100A crossing (but not a between like your chart):

http://155.178.201.160/d-tpp/1506/00237KEACH.PDF

Let me clarify... I was speaking of the SADDE fix in the currently loaded flight plan.  I didn't notice it when loading during the preflight.  Since I use the Navigraph Charts product, I saw what Neil Andrews posted above in this thread.  The LIDO charts are formatted differently from what you linked, Kyle, and that led to my confusion between the KEACH and SYMON STARs..

 

Update: However, I just figured it out.  I am filed for the RZS.KEACH1 STAR and SADDE is clearly supposed to be 250/10000.  The 10000A and 13000B restriction at SADDE is for the PMD.SYMON1 and DERBB.SYMON STARs.  This is definitely the disconnect.

 

Updated with the solution!  Sure enough, what I said above is correct.  I was trying to add a restriction that had a higher altitude than a prior way point during my descent on the flightplan.  When I deleted the earlier restriction (250/10000A), the 250/130B100A input worked flawlessly.

 

Thanks all for helping me work through this.  Self inflicted but I learned something.

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I think a few of us learned something here :) I never knew you do do a between constraint in the FMC

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