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carlan2uk

Flight Level.

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I set up a flight with    FL 34000. Before Take off I checked the legs page and found that by page  2 or 3 the FL had gone up to 38000!

I left the MCP at 34000 as planned. when top of descent appeared on the nav. display I set the MCP to 3000. At the TD the vertical path deviation

showed no deviation but  the plane did not start to descend for a long time. when it did descend, all went well to landing.

I repeated the flight after re-booting and the same thing happened again.This time I set the MCP to 38000.When into cruise at 38000 I had

to go out, so I saved the flight.. When I re-loaded,  the panel was hopeless as usual so I re-loaded the panel state. This was then ok but I had

lost a lot of height so it started to climb. BUT- the legs page now showed 34000 as it should. I quickly changed the MCP to  34000 and all went well to the end.

How is the FMC incorrect when first loading and how is it correct when  re-loading? A puzzle, an ideas?

David

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The higher flight levels you noticed later in the flight are due to the FMC planning step climbs for you as fuel is used and the 777 can fly higher. Perfectly normal, but you don't have to climb above the initial flight level if you don't want to. Just keep the MCP altitude as required.

 

I can't explain what happened after you reloaded a saved flight. The FMC simulation might behave differently in such circumstances.

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Mmmm, I'd have thought this is simply the ACARS "PERF INIT UPLOAD" ....... in other words, "flight dispatch" are deciding your FL, not you. :wink:

If you accpept the "PERF INIT" UPLOAD, it will enter the flight level, so you perhaps chose FL340, but then accepted the ACARS PERF INIT Upload, which entered FL 380 ?

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I set up the FMC exactly as in the tutorial apart from change of  start and destination.

I started from Gatwick using a long turnround. I used the information at the end of the tutorial

regarding a cold and dark startup. After a few items it then says-At this point continue with FMC setup used in the tutorial.

I did all this putting in (in my case) 34000ft. In the tutorial 38000 is inserted and all the legs showed this.

Later a choice for a step climb came but was not used.So the TD went without problem.

In my case there is no step climb as it goes straight up to 38000.

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YOu may want to contact Houston Space center if you are at FL34000, that's 3,400,000 feet.  That is barely within the atmosphere... Poor GE90s...  :lol:

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On the Perf Init page in the FMC next to the bottom right line select key the default input there is RVSM or something near that (not by FSX computer at the moment) If you leave RVSM there the FMC will work out when it expects your gross weight to be low enough to climb 4,000ft and will therefore at the appropriate waypoint show the increased flight level. If you replace RVSIM with a zero the FMC will not increase your flight level. You can also type in say 2,000 and then the FMC will when you are light enough indicate a flight level 2,000ft above your initial cruise level.

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Thank you Nixon- That did the trick.

I suppose that it is somewhere in the 2000 pages but I am not up to  that yet!¬

David

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If you leave RVSM there the FMC will work out when it expects your gross weight to be low enough to climb 4,000ft and will therefore at the appropriate waypoint show the increased flight level. If you replace RVSIM with a zero the FMC will not increase your flight level. You can also type in say 2,000 and then the FMC will when you are light enough indicate a flight level 2,000ft above your initial cruise level.

 

Almost...

 

RVSM will actually have the FMC calculate 2000' steps in RVSM airspace, and 4000' steps outside of it.  Forcing 2000' will use 2000' steps in and outside of RVSM, and 0 overrides all steps and tells the plane that you intend on remaining at your CRZ ALT on the PERF INIT page for the duration of the flight.

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Thank you Nixon- That did the trick.

I suppose that it is somewhere in the 2000 pages but I am not up to  that yet!¬

David

I am glad it helped David

Almost...

 

RVSM will actually have the FMC calculate 2000' steps in RVSM airspace, and 4000' steps outside of it.  Forcing 2000' will use 2000' steps in and outside of RVSM, and 0 overrides all steps and tells the plane that you intend on remaining at your CRZ ALT on the PERF INIT page for the duration of the flight.

Kyle why "almost"?

I was answering the specific query of the topic starter where he refers to 4,000ft. I was not defining RVSM airspace.  I don't wish to be awkward but am at a loss as why you also felt it necessary to repeat what I had written especially as the topic starter had said that the issue was now sorted.

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Kyle why "almost"?
I was answering the specific query of the topic starter where he refers to 4,000ft. I was not defining RVSM airspace.  I don't wish to be awkward but am at a loss as why you also felt it necessary to repeat what I had written especially as the topic starter had said that the issue was now sorted.

 

...why would I dare question your post?  Because it's wrong.

 

You said RVSM will make the FMC calculate when it's okay to climb 4000 feet:

 

 


If you leave RVSM there the FMC will work out when it expects your gross weight to be low enough to climb 4,000ft

^ Your words.  They essentially say "RVSM climbs are 4000."

 

This is incorrect.  The FMC will calculate when it's okay to climb 2000 feet (going along with the whole entire point of RVSM airspace - 1000 foot separation between opposite direction traffic).  Seeing that RVSM ends at FL410, and the 777's max certified ceiling is about that high, there's no real way you could argue that RVSM would regularly calculate 4000 foot steps (which it will, if you're above RVSM, but you rarely are in the bird, and you normally take a 2000 foot final step to get there).

 

Why would I feel it necessary to correct you even though the thread was "resolved?"  Because people still read posts regardless of the solution or answer being posted.  This community is already stuffed full of bad information (US 250/10 rule anyone?), so I felt it necessary to correct what you'd written.

 

The rest of it (overriding the step value) is true, but you do not need to override RVSM to get a 2000 foot step.

 

If you don't want me correcting your posts of incorrect information, either post correct information or don't post.

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Jeez Kyle, and you wonder why some people always get on your back?

 

Don't you realize your condescending tone?

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Almost...

 

RVSM will actually have the FMC calculate 2000' steps in RVSM airspace, and 4000' steps outside of it.  Forcing 2000' will use 2000' steps in and outside of RVSM, and 0 overrides all steps and tells the plane that you intend on remaining at your CRZ ALT on the PERF INIT page for the duration of the flight.

Almost...

 

Manual entered STEP climbs on the LEGs page are still taken into account for by the ETA and FUEL performance calculations even when 0 is entered.

 

Sorry Kyle.....I could not stop myself ;-)

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I set up a flight with    FL 34000. Before Take off I checked the legs page and found that by page  2 or 3 the FL had gone up to 38000!

Kyle my post was in answer to the above quote and that is why I wrote 4,000ft. As I clearly said in my last post I was not defining RVSM. Therefore I haven't posted incorrect information but instead I have answered the topic starters query and he has kindly thanked me for doing so. 

I of course don't need your permission to post. Whilst I think you posts in this thread are rude and unhelpful I certainly wouldn't tell you not to post, because I believe in the freedom of speech and the exchange of ideas.

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Therefore I haven't posted incorrect information but instead I have answered the topic starters query and he has kindly thanked me for doing so.

 

With respect Nixon, you posted:

 

 

If you leave RVSM there the FMC will work out when it expects your gross weight to be low enough to climb 4,000ft and will therefore at the appropriate waypoint show the increased flight level. If you replace RVSIM with a zero the FMC will not increase your flight level. You can also type in say 2,000 and then the FMC will when you are light enough indicate a flight level 2,000ft above your initial cruise level.

 

That implies RVSM looks for 4000 ft steps. You also said entering 2000 would give 2000 ft steps, which reinforces that impression. So even though you fixed the OP's problem, Kyle is right. The OP, and anyone else reading it, may get the idea RVSM means 4000 ft steps.

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With respect Nixon, you posted:

 

 

That implies RVSM looks for 4000 ft steps. You also said entering 2000 would give 2000 ft steps, which reinforces that impression. So even though you fixed the OP's problem, Kyle is right. The OP, and anyone else reading it, may get the idea RVSM means 4000 ft steps.

 

Kevin I presume you have read all of this thread and will have seen that I have stated twice that I was not defining RVSM. My first post said this

On the Perf Init page in the FMC next to the bottom right line select key the default input there is RVSM or something near that (not by FSX computer at the moment) If you leave RVSM there the FMC will work out when it expects your gross weight to be low enough to climb 4,000ft and will therefore at the appropriate waypoint show the increased flight level. If you replace RVSIM with a zero the FMC will not increase your flight level. You can also type in say 2,000 and then the FMC will when you are light enough indicate a flight level 2,000ft above your initial cruise level.

 

I mention RVSM solely because it is the default setting and therefore replacing it with a zero will solve the original posters query. I mentioned 2,000ft to show that the pilot can input whatever step he wishes. If I had been defining the term RVSM I would have clearly stated so and I did not. In fact I actually said "RVSM or something near that (not by my FSX computer at the moment)". I think you would agree it would be nonsensical to try and define a term when I wasn't 100% certain of the how the term is written. I would be grateful if you or Kyle could actually point to where I say am defining RVSM rather than assuming that I have defined it. 

 

I answered the original query to the satisfaction of the person who made it only for Kyle to then jump in with his "almost" remark. I then politely asked him exactly what he meant by that and also why he felt the need to virtually repeat the rest of the post.

 

His reply was in my opinion rude. Especially his last paragraph

 

.

 

If you don't want me correcting your posts of incorrect information, either post correct information or don't post.

 

Thanks to Kyle's input this thread has gone on far too long and I will therefore close with this Kyle quote which is a rather sweeping statement especially as he repeated most of my "wrong" post in his reply.

...why would I dare question your post?  Because it's wrong.

 

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Kyle my post was in answer to the above quote and that is why I wrote 4,000ft. As I clearly said in my last post I was not defining RVSM. Therefore I haven't posted incorrect information but instead I have answered the topic starters query and he has kindly thanked me for doing so. 
I of course don't need your permission to post. Whilst I think you posts in this thread are rude and unhelpful I certainly wouldn't tell you not to post, because I believe in the freedom of speech and the exchange of ideas.

 

Regardless of what you claim to be (or not to be) defining, you stated that leaving RVSM in there would have the FMC calculate when you could make a 4000' climb.  This is false.  You stated it.  It was wrong.  Admit it.  Move on.  There's no sense in trying to back pedal out of it.

 

Definition by inference is a thing.  Regardless of your intention to define what an RVSM profile looks like, you defined it, and incorrectly so.

 

This has absolutely nothing with being rude, or pointed, or anything else.  If something is wrong, it's wrong, and I'm not going to beat around the bush to avoid bruising egos.  For what it's worth, Kevin had to put up with me trying to put off that I knew more than I did, and he did it in our similarly blunt manner.  It hurt a bit, but I learned a lesson, and I learned a lot more information in the process.

 

Being wrong sucks, and it doesn't feel good, but it's not a bad thing if someone calls you out.

 

 

 


Thanks to Kyle's input this thread has gone on far too long and I will therefore close with this Kyle quote which is a rather sweeping statement especially as he repeated most of my "wrong" post in his reply.

 

Of course I did!  Part of it was right, which is why I said "almost" from the very start.

 

You included this in your post (again, I'm bringing it up in hopes that you might actually see the issue):

 

 


If you leave RVSM there the FMC will work out when it expects your gross weight to be low enough to climb 4,000ft

 

False.  There's no other way to say it, or spin that.  It's false.  Even if you didn't mean to say it, it's still false.

 

That's like me telling people that if they walk out and look at the sky, they'll see pink with green polka dots.  This is an inferred definition that the sky is pink with green polka dots.

...but I didn't intend to actually define that the sky is pink with green polka dots, so it's not wrong...?

 

 

 

What I think you're trying to get at is that with the default RVSM still in there, the plane found that it was below OPT, and calculated - in 2000' increments, mind you - that the OPT ALT was actually FL380, which happened to be 4000' higher.

 

In that case, you'd be correct, but being correct is all in how you say it.

 

Example:

"The speed limit below 10,000 is 250 knots - always."  False.

"The speed limit below 10,000 is 250 knots - with exceptions."  True.

(Above reference FAA only)

 

The main part of that answer, or factoid, is correct.  The difference in the last few words make it true and false.

 

I'm partially sorry for being so direct and blunt about my response, but this hobby is rife with poor and outright false information because people are either not specific enough (either because they're not the best at explaining things, or just don't understand it but want to try to explain it), or haven't a clue what they're talking about.  This has the potential to set people back in their learning.

 

I really don't think people in this community truly understand that every (informational) post they make has the potential to negatively or positively impact someone down the line.  So many people have this idea that "oh, well I was only responding to the OP," or "you can choose to ignore it," but people read posts regardless of who they're directed at, and if they come away from the post with incorrect information, then they're now at a disadvantage.

 

The blind adherence to the misunderstood 250/10 thing (and the subsequent vitriol if it's questioned) came from somewhere.  The fact that so many people have it wrong means that the wrong information has been perpetuated from somewhere.  Sadly, it could've been a post like this.

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Kyle

I think you ought to improve your compression skills because from your reply you don't seem to be able to grasp what am saying. I therefore can't see the point of repeating ad nauseum what I have already written. 

 

I could, like you do with other people, make many assumptions about why you decided to post here after the query had been satisfactory answered. I will not because I don't know you nor do I wish to be rude. What I will say and I have said this to you before is that you can come over as an arrogant know it all. No one not even you is right all of the time. A while ago you said that I didn't like you. I presume you made this comment because I disagreed with you. In fact you quite often make comments in that vein.For someone who seems to pride himself on speaking bluntly I find it surprising that you appear so sensitive to perceived criticism. Maybe if you spent less time at your keyboard (a view based on your nearly nine and a half thousand post in just under eight years) and more in the real world, you might become a little more empathetic.  

 

I will finish by saying that recently you appear to have toned down your response to what in your opinion are misguided or wrong posts. Yet here you seem to revert back to your old ways. In my view if that's the case it's a pity as in doing so a lot of the interesting and invaluable information that you do post tends to get overlooked. Therefore let us stop this here and hopefully you can then spend your time passing on more of your deep knowledge of aviation to us all and at the same time maybe you too will also learn a little from the others who post here.

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I would have to agree here that this thread is not headed in the appropriate direction. Kyle I understand your wanting to correct the information posted by somebody, however I do see what people are saying that some of your replies do come off with a condescending nature. 

 

*Just an outsider looking in*

 

Angelo 

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You're a good egg Kyle,  we still like you and appreciate your insights.   Keep on squashing the FUD.

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Kevin I presume you have read all of this thread and will have seen that I have stated twice that I was not defining RVSM

Of course I've read all the thread. I was the first person to answer the OP, pointing out it was a step climb issue, which is why I took an interest when more replies were added. If you weren't sure what effect the default RVSM had then it would have been better to stop after suggesting entering 0 instead of RVSM. Because what followed was at best ambiguous.

 

You didn't exactly define what the RVSM entry meant, but you clearly did say it would mean the FMC would plan a 4000' step. Using 2000' as another possibility made it look like it doesn't mean that (which of course it does). Anyone reading the post could easily take it that RVSM gives you 4000' steps which is why Kyle and myself picked up on it. I realise you didn't mean it that way but that's the way it reads.

 

It's unfortunate things got out of hand afterwards. Faults on all sides there.

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Kevin

Thanks for your reply. It's a pity that this has become an issue. From my point of view I was answering the original posters query re a step climb of 4,000ft being shown on his FMC. I didn't want to enter into an explanation of RVSM airspace, I just wanted to help the original poster. I think it would have been possible for Kyle if he so wished to have explained RVSM airspace in a more diplomatic way. I could say more but as I said earlier this is now wasting all of our time.

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For someone who seems to pride himself on speaking bluntly I find it surprising that you appear so sensitive to perceived criticism. Maybe if you spent less time at your keyboard (a view based on your nearly nine and a half thousand post in just under eight years) and more in the real world, you might become a little more empathetic.  

 

If a dog growled every time I walked by it, I could tell that it probably didn't like me.  Regardless of that observation, it doesn't mean I'm sensitive to it or upset by it.  It's merely an observation.  When it comes to my posts, you're frequently on my case for something or another.  Observation - not grief.

 

Also, if you look at the time stamps on my posts, you'll note they come at hours where I'm already stuck behind a keyboard - two birds, one stone.  As far as empathy goes, I have plenty of it, but it's usually reserved for those in dire need, or friends of mine.

 

 

 


I think it would have been possible for Kyle if he so wished to have explained RVSM airspace in a more diplomatic way. I could say more but as I said earlier this is now wasting all of our time.

 

It's not the airspace that's the issue.  Exactly as Kevin has noted, it was the way you presented RVSM in the STEP SIZE field would get you a 4000' climb.  Again, we (Kevin and I) both seem to understand where you were trying to go, now, but the way it's written is (unintentionally) misleading.

 

Interestingly enough, people get on my case for (unintentionally...usually) being condescending.  The way in which I type gives people the wrong impression.  Looks like we have a little in common.  :lol:

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Kyle

At the end of my last post I typed the quote below for two reasons. The first being there is little point in us both making the same points over and over and the second; to let you know that despite our differences I free acknowledge that you have a considerable aviation knowledge base.  

Therefore let us stop this here and hopefully you can then spend your time passing on more of your deep knowledge of aviation to us all and at the same time maybe you too will also learn a little from the others who post here.
[/quote

 

I do hope that you can accept the above as a metaphorical olive branch.  

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