Skip to content
View in the app

A better way to browse. Learn more.

The AVSIM Community

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

Step climb above max altitude?

Featured Replies

Hello,

 

Sorry if this has been discussed before but I would like to check your opinion before bothering the support team.

I have a strange issue with the step climb in the NGX

 

https://www.dropbox.com/s/utz8tb578lv17u6/Step%20NGX.jpg?dl=0

 

A picture is worth a thousand words:

 

Basically the FMC gives me a step climb pseudo-waypoint at zero nm while the step climb is above the maximum altitude.

Did anyone experience that before? Is it a misconception or a bug?

 

Thanks.

Romain Roux

204800.pngACH1179.jpg

 

Avec l'avion, nous avons inventé la ligne droite.

St Exupéry, Terre des hommes.

  • Replies 31
  • Views 7.2k
  • Created
  • Last Reply

Top Posters In This Topic

MAX ALT 356 and STEP CLIMB 360 are quite close.

 

Maybe the FMC is predicting by the time you should reach 360 (it will take a few minutes to climb) the aircraft will be lighter enough for 360?

 

Interesting.

Manuel Merelles

  • Author

Yes, it may be a possibility, but in that case the FMC would be very optimistic. It took roughly 1 hour more to get the max altitude to reach fl360.

Romain Roux

204800.pngACH1179.jpg

 

Avec l'avion, nous avons inventé la ligne droite.

St Exupéry, Terre des hommes.

This one caught my eye so I did what I always do with a question about the aircraft, I looked in the FCOM.

 

FCOM pg 11.42.20 states that the MAX is based on target speed and maneuver margins, and it is advisory only.  As long as you can maintain a climb of at least 500 fpm getting there and the speed tape shows you within safe maneuvering margins then you are good.

 

The fact that it took an hour for this value to increase 400 feet has more to do with where you are at in the safe maneuvering range than just your weight I suspect.

Dan Downs KCRP

  • Author

Thanks for the explanation, Dan and thanks to point me to the FCOM reference.

 

However, I still find it strange that despite the fact that the Max altitude is an advisory (only) value, the step climb function of the FMC allows to exceed it. I thought that it would take it into consideration while computing the step climb pseudo-waypoint.

 So I guess that it is not a bug, only the normal way the FMC of the NGX works?

 

I don't recall having seen that with the 777 either.

Romain Roux

204800.pngACH1179.jpg

 

Avec l'avion, nous avons inventé la ligne droite.

St Exupéry, Terre des hommes.

OK. The REAL aircraft will not do this. (You must have been pretty heavy at those altitudes...).

 

If you put in 360 you will get "MAX ALT FL356" on the scratchpad at the bottom and a message alert. On the right where it says now on  yours it will say "unable".

 

If there is turbulence, you really do not want to go there.....Even in smooth air it's not comfortable. If you get slow, the drag exceeds the power to recover easily and you drop to the top of the manoever margin yellow line and the autopilot drops out.

 

So, good advice from the line. In the example shown, you want to cruise at FL360 but are too heavy. Type in FL370 on the LSK1R and you will get a time and distance and a s/c drawn. When you get to this point, it's safe to climb to FL360.

 

I would NEVER climb above the limit, or indeed above the Optimum except for a few hundred feet.  You gain about 100ft Altitude capability in the cruise every 7 minutes by rule of thumb.

 

This is a fault in the simulation logic. Period. That's with u10.8a and u11.0 airplanes also.

Mark Harris.

Aged 54. 

P3D,  & DCS mostly. DofReality P6 platform partially customised and waiting for parts. Brunner CLS-E Yoke and Pedals. Winwing HOTAS and Cougar MFDS.

Scan 3XS Laptop i9-9900K 3.6ghz, 64GB DDR4, RTX2080.

B737NG Pilot. Ex Q400, BAe146, ATP and Flying Instructor in the dim and distant past! SEP renewed and back at the coal face flying folk on the much deserved holidays!

  • Commercial Member

 

 


This is a fault in the simulation logic. Period. That's with u10.8a and u11.0 airplanes also.

 

Have a reference to go with that assertion, or are you just saying that because you've never seen it?

 

Also, while I'm guessing your user name is your real name, full names are required to be in the actual post content.

Kyle Rodgers

  • Author

Hi Mark, 

 

Thanks for the info regarding the real aircraft.

 

Hi Kyle,

 

Is it worth sending a ticket for my "issue"? I cannot say that it really bothers me, it is just a matter of whether reporting a potential bug to the support team.

 

Thanks.

Romain Roux

204800.pngACH1179.jpg

 

Avec l'avion, nous avons inventé la ligne droite.

St Exupéry, Terre des hommes.

Well, I was flying TC-SBP a 737-800 msn 36672 this morning and can confirm this aircraft u10.8a acts as I stated. Also same in TC-SCD a u11.0 equipped aircraft.

 

FCOM says:

 

-Entering an altitude above the airplanes maximum certified altitude displays the error massage INVALID ENTRY

-Entering an altitude above the MCP altitude but below the MAX altitude displays the message RESET MCP ALTITUDE

-Entering an altitude below the airplanes maximum certified altitude and above the MAX altitude on the CRZ page displays the message MAX ALT (altitude).

-The RTA prompt 9LSK 6R) changes to an ERASE prompt when a new CRZ ALT is entered.

 

If you wish, I have a long boring run to DUS from ESB and down to AYT overnight I can play and take a few pictures to post...

 

Mark Harris 

Mark Harris.

Aged 54. 

P3D,  & DCS mostly. DofReality P6 platform partially customised and waiting for parts. Brunner CLS-E Yoke and Pedals. Winwing HOTAS and Cougar MFDS.

Scan 3XS Laptop i9-9900K 3.6ghz, 64GB DDR4, RTX2080.

B737NG Pilot. Ex Q400, BAe146, ATP and Flying Instructor in the dim and distant past! SEP renewed and back at the coal face flying folk on the much deserved holidays!

  • Commercial Member

 

 


If you wish, I have a long boring run to DUS from ESB and down to AYT overnight I can play and take a few pictures to post...

 

That would help. I always cringe at entering a ticket into the bug tracker with "well, some random dude on the internet said this isn't right."

 

The FCOM references help, too.

Kyle Rodgers

I have plenty of time tonight and will need something to keep awake, my lovely employers have no idea of flight Time Limitations to be honest....

Mark Harris.

Aged 54. 

P3D,  & DCS mostly. DofReality P6 platform partially customised and waiting for parts. Brunner CLS-E Yoke and Pedals. Winwing HOTAS and Cougar MFDS.

Scan 3XS Laptop i9-9900K 3.6ghz, 64GB DDR4, RTX2080.

B737NG Pilot. Ex Q400, BAe146, ATP and Flying Instructor in the dim and distant past! SEP renewed and back at the coal face flying folk on the much deserved holidays!

  • Author

Same for me, I have a couple of flights planned with the NGX. I will check according to the FCOM and take some screenshots as well.

Romain Roux

204800.pngACH1179.jpg

 

Avec l'avion, nous avons inventé la ligne droite.

St Exupéry, Terre des hommes.

He He, mine isn't an NGX though. Just probably a 737-8HC if I'm lucky.....

Mark Harris.

Aged 54. 

P3D,  & DCS mostly. DofReality P6 platform partially customised and waiting for parts. Brunner CLS-E Yoke and Pedals. Winwing HOTAS and Cougar MFDS.

Scan 3XS Laptop i9-9900K 3.6ghz, 64GB DDR4, RTX2080.

B737NG Pilot. Ex Q400, BAe146, ATP and Flying Instructor in the dim and distant past! SEP renewed and back at the coal face flying folk on the much deserved holidays!

Well, I was flying TC-SBP a 737-800 msn 36672 this morning and can confirm this aircraft u10.8a acts as I stated. Also same in TC-SCD a u11.0 equipped aircraft.

 

FCOM says:

 

-Entering an altitude above the airplanes maximum certified altitude displays the error massage INVALID ENTRY

-Entering an altitude above the MCP altitude but below the MAX altitude displays the message RESET MCP ALTITUDE

-Entering an altitude below the airplanes maximum certified altitude and above the MAX altitude on the CRZ page displays the message MAX ALT (altitude).

-The RTA prompt 9LSK 6R) changes to an ERASE prompt when a new CRZ ALT is entered.

 

If you wish, I have a long boring run to DUS from ESB and down to AYT overnight I can play and take a few pictures to post...

 

Mark Harris

Wait a second! U11 finally came out?

Matt Cee

  • Author

He He, mine isn't an NGX though. Just probably a 737-8HC if I'm lucky.....

 

Oups, I didn't get that you are talking about a real flight!  :ph34r: (or am I confusing? English is not my native language and I may miss some meaning...)

 

I'm not that lucky as I'm not a real pilot... I will make do with the NGX in FSX! 

Romain Roux

204800.pngACH1179.jpg

 

Avec l'avion, nous avons inventé la ligne droite.

St Exupéry, Terre des hommes.

Create an account or sign in to comment

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.