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J van E

MD-11 CRZ LEVELS in INIT page

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I somehow can't figure out what's the use of entering more than one alt in the CRZ LEVELS entry on the INIT page. I tried to fly a real life plan for the first time today (EGSS-LFPG: N0455F170 LYD G27 WAFFU/N0490F230 M605 XIDIL UM605 DP) and entered 170/230 into that part of the INIT page, but the plane only noticed that FL170 and stayed there all the time... So... what's the use of adding more FL levels...? The FMS manual didn't help me...

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That is a pretty short trip. Multiple levels are handy for long flights where step climbs are used to improve economics.

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I like them short. ;) It's a FedEx trip: I installed the FedEx livery and started to fly those real life trips: big fun!But you didn't answer the question (at least know that I am aware... :( ) Suppose this WAS a long trip and I entered 170/230: what's the use of entering 230 when the plane only seems to follow the first level? How does the plane know when to go to the next level...? Should I enter all levels into the plan manually? If so, what's the use of entering them here? I probably am overlooking something obvious...

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The distance is the point. It would climb to FL230 if there were an advantage.

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I like them short. ;)But you didn't answer the question (at least know that I am aware... :( ) Suppose this WAS a long trip and I entered 170/230: what's the use of entering 230 when the plane only seems to follow the first level? How does the plane know when to go to the next level...? Should I enter all levels into the plan manually? If so, what's the use of entering them here? I probably am overlooking something obvious...
Jeroen,The levels you enter here on a short flight look more like FL restrictions on the airway. You better enter them on the FlightPlan pages as 170 or below and 230 or above.As Dan states, the sequence of levels entered on the init page are to improve economics. So start at least near an Optimum level, and enter next requested optimum levels in sequence, so the FMS can predict the optimum S/C points.The steps to make depend on the airspace structure, allowing 1000, 2000 or 4000 ft steps.Hope this clears it a bit.Regards,Harry

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The distance is the point. It would climb to FL230 if there were an advantage.

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I like them short. ;)But you didn't answer the question (at least know that I am aware... :( ) Suppose this WAS a long trip and I entered 170/230: what's the use of entering 230 when the plane only seems to follow the first level? How does the plane know when to go to the next level...? Should I enter all levels into the plan manually? If so, what's the use of entering them here? I probably am overlooking something obvious...
On longer flights airliners perform so called step climbs, to get to a higher altitude as they get lighter. This is done to burn less fuel and thus increase range and save money.What you are doing by entering multiple flight levels, is to let the FMC know how big you want the "steps" to be. On Boeing aircraft you can enter a "step climb size", which will essentially do the same. Now if you enter flight levels that are for instance 2000 feet apart (330, 350, 370, 390) the FMC will calculate optimum points of climb for you. When you approach a step climb you still have to manually adjust the altitude on the MCP (AFS on the 11?). This is to prevent the aircraft to climb automatically without clearance from ATC.RegardsAlex

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I like them short. ;)But you didn't answer the question (at least know that I am aware... :( ) Suppose this WAS a long trip and I entered 170/230: what's the use of entering 230 when the plane only seems to follow the first level? How does the plane know when to go to the next level...? Should I enter all levels into the plan manually? If so, what's the use of entering them here? I probably am overlooking something obvious...
On longer flights airliners perform so called step climbs, to get to a higher altitude as they get lighter. This is done to burn less fuel and thus increase range and save money.What you are doing by entering multiple flight levels, is to let the FMC know how big you want the "steps" to be. On Boeing aircraft you can enter a "step climb size", which will essentially do the same. Now if you enter flight levels that are for instance 2000 feet apart (330, 350, 370, 390) the FMC will calculate optimum points of climb for you. When you approach a step climb you still have to manually adjust the altitude on the MCP (AFS on the 11?). This is to prevent the aircraft to climb automatically without clearance from ATC.RegardsAlex

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Thanks for all the answers. It's clear now! Posting some replies twice helped a lot... :( (Only kidding: I also had severe problems getting things posted during that time!!!)

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I know, this forum's performance is inadequate sometimes and impossible the rest.

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I just what to add an another question to this.Is it possible to enter scheduled step downs?This route:EFHK N0470F320 PIVAK P854 PIR UY70 PRI/N0467F340 UL80 TOGMI UP855 ABADA DCT 65N000E/M082F340 66N010W 66N020W 65N030W/M082F300 63N040W 59N050W DCT LOACH DCT FOXXE/N0471F360 N264A TAFFY/N0471F400 DCT ENE ENE4 KJFKshows a scheduled step down at 65N030W to FL300. Whenever I try to add this using the INIT page, I get invalid step down, or something a long those lines.Would I have to manually enter this altitude in the Vertical Reference page for the said waypoint?

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I just what to add an another question to this.Is it possible to enter scheduled step downs?This route:EFHK N0470F320 PIVAK P854 PIR UY70 PRI/N0467F340 UL80 TOGMI UP855 ABADA DCT 65N000E/M082F340 66N010W 66N020W 65N030W/M082F300 63N040W 59N050W DCT LOACH DCT FOXXE/N0471F360 N264A TAFFY/N0471F400 DCT ENE ENE4 KJFKshows a scheduled step down at 65N030W to FL300. Whenever I try to add this using the INIT page, I get invalid step down, or something a long those lines.Would I have to manually enter this altitude in the Vertical Reference page for the said waypoint?
Looks like a real world flightplan there! In which case the drop down would be to miss a bad windage in the jetstream. Dispatch planning is wonderful. And yes you would need to implement the step down manually as it's probably outside the 'envelope' for that stage of flight.If you're using fs weather of course there is no need to.John Ellison

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The FCOM warns against entering step descents. If I recall, the FMC either won't take it, or enter descent phase indefinitely. Either way, don't try it.

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The FCOM warns against entering step descents. If I recall, the FMC either won't take it, or enter descent phase indefinitely. Either way, don't try it.
An intermediate descent can simply be done by descending to the required altitude AND re-entering that new altitude on the INIT Page to re-enter the Cruise Mode.Would not be surprized if in this Flightplan the intermediate step-down was planned due to low fuel temps.Regards,Harry

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Apologies if it looked like I was saying not to descend. I was saying don't do it with the /SXX command.
Paul,Reading it now as you intended.Harry

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