Sigmund0428

Wrong Step Climb Altutudes

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I am flying a long haul heading westbound.  Initial cruise altitude is FL320.  My question is shouldn’t my next altitude be an even number i.e FL340?  I was always under the assumption of your flying west you would have an even FL and flying east you would have an odd FL.   My fmc is calculating my step climb altitude of FL350.

 

Thanks

- Sigmund Horn

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Just now, Captain Kevin said:

Did you set your step size to 2000?

I did not 😩. So many things I’ve gotten use to on the 744.   Never had to change the step size till today.  Thanks for the tip!  

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5 minutes ago, Sigmund0428 said:

I did not 😩. So many things I’ve gotten use to on the 744.   Never had to change the step size till today.  Thanks for the tip!  

Stupid question, but how did you NOT have to do it on the 747-400. I've always had to do it because it otherwise defaulted to ICAO, which is apparently 4,000 rather than 2,000.

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Several years ago Rod Machado did a presentation about automation in the cockpit and people becoming unable to fly themselves... he called it „children of the magenta line“ 😝

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2 hours ago, Captain Kevin said:

Stupid question, but how did you NOT have to do it on the 747-400. I've always had to do it because it otherwise defaulted to ICAO, which is apparently 4,000 rather than 2,000.

Ditto,same procedure here for step climb.Had no issue.

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Gents,

Just a quick run through, and a bit of (very high level) history:

The 744 came out in 1988. RVSM didn't hit until 1997 (selectively - completed in 2007).

 

Before RVSM (reduced vertical separation minima), aircraft were separated by five miles and 2000' vertically between FL290 and FL410, to be sure altimeter errors didn't put opposite direction traffic in harm's way. This meant that you had to use FL290 eastbound, FL310 westbound, FL330 eastbound, and FL350 westbound (why you were seeing FL350 - it was the next highest "legitimate" westbound altitude), and so on (doing the math, that means 4000' steps).

As technology got better, we were able to track altitude a lot better, so if your aircraft was properly equipped, you could get RVSM approved (some planes still aren't btw). This reduced it down to 1000' vertically between all the way up to FL410 (still 2000' above that even today), which is the East-Odd; West-Even you're used to.

As such, when you see ICAO in the 744, you're getting 2000' steps up to FL290, and then 4000' steps above that. Because that was pre-RVSM, most simmers overwrite this with 2000 to simulate having RVSM approval. Of course, looking at the 748, you see RVSM now, which is 2000' steps up through FL410, and then it would use 4000' thereafter.

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25 minutes ago, scandinavian13 said:

Gents,

Just a quick run through, and a bit of (very high level) history:

The 744 came out in 1988. RVSM didn't hit until 1997 (selectively - completed in 2007).

 

Before RVSM (reduced vertical separation minima), aircraft were separated by five miles and 2000' vertically between FL290 and FL410, to be sure altimeter errors didn't put opposite direction traffic in harm's way. This meant that you had to use FL290 eastbound, FL310 westbound, FL330 eastbound, and FL350 westbound (why you were seeing FL350 - it was the next highest "legitimate" westbound altitude), and so on (doing the math, that means 4000' steps).

As technology got better, we were able to track altitude a lot better, so if your aircraft was properly equipped, you could get RVSM approved (some planes still aren't btw). This reduced it down to 1000' vertically between all the way up to FL410 (still 2000' above that even today), which is the East-Odd; West-Even you're used to.

As such, when you see ICAO in the 744, you're getting 2000' steps up to FL290, and then 4000' steps above that. Because that was pre-RVSM, most simmers overwrite this with 2000 to simulate having RVSM approval. Of course, looking at the 748, you see RVSM now, which is 2000' steps up through FL410, and then it would use 4000' thereafter.

I guess I'm wondering how the FMC told him to go to 350 when he was initially at 320.

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37 minutes ago, Captain Kevin said:

I guess I'm wondering how the FMC told him to go to 350 when he was initially at 320.

Have a look back at my earlier post...

The next valid westbound altitude is FL350 if you leave the step as ICAO. Absent a specific reference to the 8, I have to assume he's in the 400 if the steps are using ICAO. If you're not using 2000 or RVSM, you don't use even altitudes at all, above 290, so from 320, 330 would be skipped because it's eastbound (and <2000'), leaving 350 as the next.

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6 hours ago, scandinavian13 said:

Have a look back at my earlier post...

The next valid westbound altitude is FL350 if you leave the step as ICAO. Absent a specific reference to the 8, I have to assume he's in the 400 if the steps are using ICAO. If you're not using 2000 or RVSM, you don't use even altitudes at all, above 290, so from 320, 330 would be skipped because it's eastbound (and <2000'), leaving 350 as the next.

Copy, guess I wasn't quite understanding how it worked, as I had thought it would have just added 4,000 to put him at 360, but I guess not. Interesting.

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On 9/24/2018 at 4:21 AM, Ephedrin said:

Several years ago Rod Machado did a presentation about automation in the cockpit and people becoming unable to fly themselves... he called it „children of the magenta line“ 😝

While I agree with what you’re saying I don’t understand why you felt the need to reply with this???  I’m not a real pilot but I do hand fly in the sim quite a bit.  I asked a question which people do all the time.  

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Thanks everyone for the reply!  Some very helpful information and some not some much lol.  I appreciate the responses.

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58 minutes ago, Sigmund0428 said:

While I agree with what you’re saying I don’t understand why you felt the need to reply with this???  I’m not a real pilot but I do hand fly in the sim quite a bit.  I asked a question which people do all the time.  

Probably because simmers have a very, very (very) strong tendency to rely too much on automation without getting curious as to why the automation is doing what it's doing. This manifests as blind trust, or probably more frequently, putting their own ideas of what it should be doing based on limited experience, and wondering if the difference is caused by a bug instead of their misunderstanding. I don't think that's necessarily the case here, but it's something simmers with a little more experience notice, and the real world pilots as well.

Note that your thread title could come across as an assertion: "the plane is giving me wrong altitudes," which means the assertion is that the automation is incorrect. In the thread itself, of course, you do somewhat concede the point that you're not entirely sure by asking the question "shouldn't it be..." but in the end, the leading message people get (by seeing the thread title before even getting the rest) is: "this is wrong." In reality, of course, it's a misunderstanding of the automation, and not taking the time to understand the automation leads into Sigmund's point of people being overly reliant on it. The concept of RVSM is not related to automation, but it only came up due to the over reliance on the automation to determine how the climb schedule would go, instead of understanding the concept the automation was built upon (ICAO being non-RVSM steps).

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Yip, that was my intension. And I‘m always joking a bit, never (almost never) want to be offensive. I was holding a PPL, flew C172 mainly, carburator engine. When I couldn‘t do that anymore I came across the flight simulation and the forums. PMDG was quite alone on the high quality market and people around FS9 and FSX were used to the 747 and the level d 767. As a pilot you learn that YOU fly the airplane. We didn‘t even have any autopilots. But anyway whatever the airplane does, never expect it to be correct. Check it, if it‘s not ok correct it. But as PMDG and Level d were the only ones providing really good addons and they both only do airliners (A2A quality in GA planes was unknown) people were used to fill in the empty boxes in the CDU, call this correctly programming the FMS and finally engaging the autopilot. Lacking good charts and airac you had to try the stars available in the fms and land that thing. And today many many simmers still do it exactly that way. Flight level rules, general understanding of how the massiv air traffic works and knowledge of the system of the airplane, at least to a certain degree, is often simply not there. That‘s in no way meant rude, it‘s just a fact.. and that‘s why I joked about that magenta line.. it wasn‘t meant personally or anything, just a comment with that background 😄 whenever the airplane is not doing what you expect it to do, take control and change it. When you don‘t understand what it does, search for information, but don‘t let it just do what it does and say „must be correct, it‘s an aurplane“ 😄 

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9 minutes ago, Ephedrin said:

Yip, that was my intension. And I‘m always joking a bit, never (almost never) want to be offensive. I was holding a PPL, flew C172 mainly, carburator engine. When I couldn‘t do that anymore I came across the flight simulation and the forums. PMDG was quite alone on the high quality market and people around FS9 and FSX were used to the 747 and the level d 767. As a pilot you learn that YOU fly the airplane. We didn‘t even have any autopilots. But anyway whatever the airplane does, never expect it to be correct. Check it, if it‘s not ok correct it. But as PMDG and Level d were the only ones providing really good addons and they both only do airliners (A2A quality in GA planes was unknown) people were used to fill in the empty boxes in the CDU, call this correctly programming the FMS and finally engaging the autopilot. Lacking good charts and airac you had to try the stars available in the fms and land that thing. And today many many simmers still do it exactly that way. Flight level rules, general understanding of how the massiv air traffic works and knowledge of the system of the airplane, at least to a certain degree, is often simply not there. That‘s in no way meant rude, it‘s just a fact.. and that‘s why I joked about that magenta line.. it wasn‘t meant personally or anything, just a comment with that background 😄 whenever the airplane is not doing what you expect it to do, take control and change it. When you don‘t understand what it does, search for information, but don‘t let it just do what it does and say „must be correct, it‘s an aurplane“ 😄 

Yeah, you and I see eye to eye a lot on many of your points...

Also: I was lamenting the lack of "study sim" C172s that we have now to someone earlier, too. It would've made my initial training so much easier just to have something to help me run through checklists.

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2 hours ago, scandinavian13 said:

Probably because simmers have a very, very (very) strong tendency to rely too much on automation without getting curious as to why the automation is doing what it's doing. This manifests as blind trust, or probably more frequently, putting their own ideas of what it should be doing based on limited experience, and wondering if the difference is caused by a bug instead of their misunderstanding. I don't think that's necessarily the case here, but it's something simmers with a little more experience notice, and the real world pilots as well.

Note that your thread title could come across as an assertion: "the plane is giving me wrong altitudes," which means the assertion is that the automation is incorrect. In the thread itself, of course, you do somewhat concede the point that you're not entirely sure by asking the question "shouldn't it be..." but in the end, the leading message people get (by seeing the thread title before even getting the rest) is: "this is wrong." In reality, of course, it's a misunderstanding of the automation, and not taking the time to understand the automation leads into Sigmund's point of people being overly reliant on it. The concept of RVSM is not related to automation, but it only came up due to the over reliance on the automation to determine how the climb schedule would go, instead of understanding the concept the automation was built upon (ICAO being non-RVSM steps).

I see and I understand completely!  I can see how the title is misleading.  I appreciate your honesty and thanks again for the help.

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51 minutes ago, Ephedrin said:

Yip, that was my intension. And I‘m always joking a bit, never (almost never) want to be offensive. I was holding a PPL, flew C172 mainly, carburator engine. When I couldn‘t do that anymore I came across the flight simulation and the forums. PMDG was quite alone on the high quality market and people around FS9 and FSX were used to the 747 and the level d 767. As a pilot you learn that YOU fly the airplane. We didn‘t even have any autopilots. But anyway whatever the airplane does, never expect it to be correct. Check it, if it‘s not ok correct it. But as PMDG and Level d were the only ones providing really good addons and they both only do airliners (A2A quality in GA planes was unknown) people were used to fill in the empty boxes in the CDU, call this correctly programming the FMS and finally engaging the autopilot. Lacking good charts and airac you had to try the stars available in the fms and land that thing. And today many many simmers still do it exactly that way. Flight level rules, general understanding of how the massiv air traffic works and knowledge of the system of the airplane, at least to a certain degree, is often simply not there. That‘s in no way meant rude, it‘s just a fact.. and that‘s why I joked about that magenta line.. it wasn‘t meant personally or anything, just a comment with that background 😄 whenever the airplane is not doing what you expect it to do, take control and change it. When you don‘t understand what it does, search for information, but don‘t let it just do what it does and say „must be correct, it‘s an aurplane“ 😄 

I get it now!  Wasn’t sure if you were trolling 😂!  I’ve spent a lot of time flying the 744 since it was first released.  I’ve made it a point to learn the airplane as much as I can by reading the FCOM and trying not to only rely on the AP.  My apologies for assuming you were just being a troll.  Thanks for clarifying and like I said I do agree there are a lot of RL pilots and summers who solely rely on the AP.  I managed my issue on that flight by manually entering my desired FL for the step climb so it worked out.  I’ve just never had to change the step size in the time I’ve flown the 744 which has been well over 10 years so when this issue arised I wasn’t prepared.   That’s why I mentioned I probably should re read the FCOM to brush up on my knowledge of the aircrafts systems.  Thanks again!!!

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Haha no problem! 

In my opinion there is nothing wrong in relying on the AP. But it would always be good to understand the mode you are using. The Boeing MCP today is pretty well tidied up, but still has every button only one function, more or less. Of course the logic behind VNAV or the idea behind a mode like FL Change is a bit more complicated than VS or LOC, but in my early days not knowing anything about advanced autopilots I used LNAV and VS constantly seeing my engines spooling up and down and me changing the values to keep my speed save. There is so much to learn in complex aviation, most people who aren‘t airline pilots don‘t know all that stuff. RVSM.. no 172 pilot cares about that. The highest I have ever flown was 11000ft approaching Innsbruck 😄 And I‘m sure there are many airline pilots who don‘t know the VFR limits 😄

Btw... the MD-82 confuses me totally xD

 

of course, here we are in a safe world and nothing happens if we use the wrong flight level. But at some point I think after paying 140€ for an addon I am motivated to really get to know it 😄 

Edited by Ephedrin
Forgot a „don‘t“ :D
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