Yes i know that but why isn't it in the FCOM? I've searched everywhere for it

 

FCTM 1.46 alludes to it:

"[...] during climbs, maximum or hard altitude constraints should be set in the MCP. Minimum crossing altitudes need not be set in the MCP. The FMC alerts the crew if minimum altitude constraints will not be met.

 

FCOMv2 11.31.24 discusses ALT INTV.

 

The rest is really just common sense, honestly. Think of the SIDs out of AMS (EHAM). They have initials down at 6000. In the DC area, PFPX will give you an initial of 17000 clear up through NY for European departures. Even that wouldn't be your listed cruise altitude (because ATC will cancel that restriction quite readily - the 17000 restriction is usually only placed on DC -> NY flights on those routes).

 

Your cruise altitude is the one that you want. Doesn't matter how many restrictions are there or for how long. The cruise altitude in the FMC should be the one you filed for. The FMC needs to know where you're going to cruise.

 

Basically, think of it like this:

Every flight is the same, basic, climb-cruise-descend. Ignore altitude restrictions on SIDs/STARs and so on. What is your cruising altitude for this flight? FL390. Okay, put that in the FMC. Now...restrictions? Okay, handle those on the LEGS page if they're tied to fixes, or handle them on the MCP if they're restrictions not associated with fixes (ATC assigned ones).

Yes i know that but why isn't it in the FCOM? I've searched everywhere for it

I would imagine it's not in the FCOMS or FCTM because those volumes are about how operate the plane correctly. They don't address what can go wrong if you do this or that incorrect procedure

Thanks kyle totally understand it. Thanks for going out your way. From now on i'll enter my final cruise alt in the FMC and handle the rest with the MCP.

 

Still puzzled why you didn't get a VNAV DISCONNECT and i did....

 

Thanks again!!!

 

 

Thanks kyle totally understand it. Thanks for going out your way. From now on i'll enter my final cruise alt in the FMC and handle the rest with the MCP.

 

You're welcome. It's what I'm here for. I'll post a video with the three test cases in a few just so you can see if you're doing something slightly different.

Can you record through FSX? I'll see what i can do aswell and try get a video up too.

 

Have a good one.

I would imagine it's not in the FCOMS or FCTM because those volumes are about how operate the plane correctly. They don't address what can go wrong if you do this or that incorrect procedure

This about sums it up... This error is a direct result of improper procedures not outlined in any flight or normal procedure manual because it isn't a normal procedure. As to why Kyle didn't get a VNAV disconnect, I would wait to watch his video on an iPad and as he operates his test flight, you do the same. I'm interested in hearing if after you followed along with his video you still get a disconnect. 

 

Vernon, I think your understanding of how to correctly and procedurally manage altitudes AND restrictions needs a little improvement and that will just come by practice and the willingness to accept what you have been doing is not the correct method. 

 

Instead of posting copyright material, I'll reference my copy of the 737NG FCOM, which references ALT INTV. ALT INTV is: A function which allows the manual deletion of next FMC altitude constraint (restriction) via altitude SEL (MCP ALT) and ALT INTV switch. Therefore, you should only use the ALT INTV function in circumstances which require you to bypass a temporary altitude restriction on way to the next programmed altitudes in the FMC. If you want to step climb or otherwise maintain an altitude from an altitude assignment by a controller without having pre-programmed or otherwise required altitude restrictions in the FMC, simply place the cleared altitude into the MCP ALT and continue on VNAV.

. As to why Kyle didn't get a VNAV disconnect, I would wait to watch his video on an iPad and as he operates his test flight, you do the same. I'm interested in hearing if after you followed along with his video you still get a disconnect. [/size]

 

Vernon, I think your understanding of how to correctly and procedurally manage altitudes AND restrictions needs a little improvement and that will just come by practice and the willingness to accept what you have been doing is not the correct method. [/size]

 

I'm just puzzled at why he didn't get a DISCONNECT. I'll watch his video closely though once posted up.

 

Yeh its only been 8months with this bird. I'm actuallu going from the AUTO FLIGHT SYSTEM the now, to get a good grasp! It can be confusing!!!

Here ya go (please do not share this - it's only meant for this thread and this thread alone*):

 

https://www.youtube.com/watch?v=zmAY-X1VLoY

 

 

 

*Won't be the end of the world. I just don't want people - despite my disclaimer at the beginning - using this as a reference of what is proper.

Kyle i done case test 1 and it worked BUT only if you hit ALT INV ONCE, if i hit ALT INV TWICE i get the VNAV DISCONNECT.

 

CAN YOU PLEASE try doing the test BUT hit ALT INV more than ONCE?

 

Thankyou

Its a bug no doubt if you hit ALT INV TWICE you get the VNAV DISCONNECT

 

 

Its a bug no doubt if you hit ALT INV TWICE you get the VNAV DISCONNECT

 

Not a bug.  Each time you press the button something happens and if it runs out of constraints to delete it simply disconnects. See FCOM 4.10.10

 

Push – (during VNAV climb)

•lowest FMC altitude constraint below selected MCP altitude is deleted

•if airplane is currently at an FMC altitude constraint, deletion allows airplane to resume climb. MCP altitude must be set above current altitude•for each press of switch, one deletion occurs

•if MCP altitude is set above current FMC altitude, FMC cruise altitude resets to MCP altitude. FMC cruise altitude cannot be decreased using ALT INTV switch.

Right so thats why i'm getting that VNAV DISCONNECT by pressing it more than once.

 

Problem solved

 

 

Right so thats why i'm getting that VNAV DISCONNECT by pressing it more than once.

 

Yeah - I demonstrated this right at 4:15 (the lead in to that is probably somewhere around 3:50).

Problem solved we can all go home

 

Kyle thankyou so much for the support throughout and the work of the video.

 

Good stuff

 

 

Kyle thankyou so much for the support throughout and the work of the video.

 

Welcome! Glad we could put that one to bed. Enjoy the flying.

Yeh certainly kyle! Will do cheers