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Max Alt 737-800

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Why is the max altitude of the 737-800 on the fmc so low, The service celing is 41000 and after t/o I cant even make it to 370 or the fmc gives me a message like max alt 351. Even when I am about to decend an have burned alot of fuel it never reaches even 390.

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It really depends on your load. I've had the -800 at 370 and 390 but only when lightly loaded.

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I flew in a 737-800 the other day and did the exact same flight in fs. I wasnt extra heavy or anything. On the real flight we made it to 370, then 390, I could not do this in the pmdg plane.

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>> The service celing is 41000 and after >>You should double check this figure. A quick search on the>internet shows that 737-800's service ceiling is 11,582 meters>and after conversion to feet you get exactly 38,000 ft.>>Michael J.The certified Maximum Operating Altitude for the 73NG series is 41,000 ft according to the FAA approved type certificate. Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpg

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>I flew in a 737-800 the other day and did the exact same>flight in fs. I wasnt extra heavy or anything. On the real>flight we made it to 370, then 390, I could not do this in the>pmdg plane.Did you have a copy of their flight plan with fuel and load figures? It's tough to replicate a real world flight if you don't have those figures. Fuel and payload have a large affect on cruising altitudes. What was your payload, fuel load and flight plan distance?Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpg

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>The certified Maximum Operating Altitude for the 73NG series>is 41,000 ft according to the FAA approved type certificate. This would be called the absolute ceiling versus the service ceiling we are talking about. FAA clearly distinguishes both.Michael J.http://www.precisionmanuals.com/images/for...argo_hauler.gifhttp://sales.hifisim.com/pub-download/asv6-banner-beta.jpg

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>I flew in a 737-800 the other day and did the exact same>flight in fs. I wasnt extra heavy or anything. On the real>flight we made it to 370, then 390, I could not do this in the>pmdg plane.Are you a real 737 pilot? Somehow I have a feeling this is not the case. But then how would you know how high you flew or what your weight was :-hmmm :-hmmmMichael J.http://www.precisionmanuals.com/images/for...argo_hauler.gifhttp://sales.hifisim.com/pub-download/asv6-banner-beta.jpg

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A look in the flight manual shows that max weight for a B737-800 at 41000 ft is 125000 lb.The B738 routinely operates at fl400 on short sectors.That is in the real world. James

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I am not a real 737 pilot. The video screens in flight have a satelite map that shows the altitude. I happen to know the flight was full and we had extra fuel to cover delays that we had anticipated, so the plane was loaded pretty good. Flight distance was about 1750 nm.

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>>The certified Maximum Operating Altitude for the 73NG>series>>is 41,000 ft according to the FAA approved type certificate.>>>This would be called the absolute ceiling versus the service>ceiling we are talking about. FAA clearly distinguishes both.No, this is the certified maximum altitude and is also the figure in the FAA aproved 73NG flight manuals. If the aircraft is performance limited to an altitude below its certified max. then that is the service ceiling which can max out at FL410. Being a 737 mechanic I'm more than familiar with the type and have been on NG's up to FL410 although FL390-FL400 seem to be the norm on legs up to 4 hours.EDIT: I'm saying this because of your claim of a max service ceiling of 38,000 ft for the 737-800 where as a lightly loaded 800 CAN go to 41,000ft.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpg

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>I am not a real 737 pilot. The video screens in flight have>a satelite map that shows the altitude. I happen to know the>flight was full and we had extra fuel to cover delays that we>had anticipated, so the plane was loaded pretty good. Flight>distance was about 1750 nm.people take up little weight. how much fuel? do you know? and how about cargo and luggage load? seriously, dont make assumptions. The 738 goes up to FL400 and 410 all the time, especially with companies like Southwest who love fuel efficiencyand one more thing, the GPS altitude is not the same altitude as what the pilots see. because they reset their altimiter to standard after passing 18,000 feet, but rarely is the atmopshere at standard pressure.

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The flight was from kslc to kewr. This is not just one occurance this happens with pretty much all of my 737 flights even with the center tanks empty.

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>EDIT: I'm saying this because of your claim of a max service>ceiling of 38,000 ft for the 737-800 where as a lightly loaded>800 CAN go to 41,000ft.Regardless what the service ceiling for 737-800 is (I accept that it could be 41,000 ft if you say so) you seem to have no idea what is the difference between service ceiling and absolute ceiling (I guess mechanics don't have to know these things). I suggest you look it up. Yes, the aircraft can climb above its service ceiling. And, by the way, absolute ceiling is not the same as maximum certified altitude. So yes, aviation loves different terms and they all mean slightly different things.Michael J.http://www.precisionmanuals.com/images/for...argo_hauler.gifhttp://sales.hifisim.com/pub-download/asv6-banner-beta.jpg

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>>EDIT: I'm saying this because of your claim of a max>service>>ceiling of 38,000 ft for the 737-800 where as a lightly>loaded>>800 CAN go to 41,000ft.>>Regardless what the service ceiling for 737-800 is (I accept>that it could be 41,000 ft if you say so) you seem to have no>idea what is the difference between service ceiling and>absolute ceiling (I guess mechanics don't have to know these>things). I suggest you look it up. Yes, the aircraft can climb>above its service ceiling. And, by the way, absolute>ceiling is not the same as maximum certified altitude. So yes,>aviation loves different terms and they all mean slightly>different things.I am well aware of Service Ceiling and Absolute Ceiling and am very annoyed at your constant demeaning attitude towards those that know what they're talking about. Put your attitude aside and listen to the facts for once.Service Ceiling: Best Rate of Climb speed with max continous power where rate of climb is 100 fmp.Absolute ceiling:The aircraft can not climb any higher with max continous power at best rate of climb speed.As I said, the entire 73NG series is certified to a Max Altitude of 41,000 ft. Do you know why? I do!! It can climb higher but isn't certified to do so. If you want to know just ask!BTW, I must have been dreaming on a recent 737-800 flight from CYYC to KPHX as we were cruising at FL390. A good 1000' above your quoted max ceiling! Maybe you should recheck your figures.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpg

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>I am glad we agree on the definitions. ;)>I take your numbers - as I said above my '38000' was based on>some google search - I never guaranteed it was 100% correct.>Best.By your responses to me I kind of doubt your last sentence ;-)OK now that we understand one another, the 73NG Max Certified Altitude is determined by the ability of the pressurization system to maintain an 8000' cabin altitude at a max diferential pressure of 9.1 psi. This equates to a 41,000 ft max certified altitude.For future reference here is a link to the FAA Type Certificate Data Sheets.http://www.airweb.faa.gov/Regulatory_and_G...me?OpenFrameSetEdited for spellingCheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpg

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SO is their something wrong with the pmdg code, because the fmc never lets me above 350 initially.

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>SO is their something wrong with the pmdg code, because the>fmc never lets me above 350 initially.you never answered my questions. how many people and how much cargo was this real world flight?the biggest question to why the FMC wouldnt allow you above 350 would be "CI" cost index.

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I always stick with Cost Index 90 for both 744 and 737. That way, given my chosen payload, i get what kind of initial flight level and performance i am looking for first time round. I'm not sure if that is the correct way of going about things but it has always worked for me.

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>the biggest question to why the FMC wouldnt allow you above>350 would be "CI" cost index.Actually Cost Index should have no bearing on cruise altitude for the trip in question. If your trip length is very short <300nm or you have a very low CI which limits the maximum possible altitude based on the selected target speed then it's possible. CI is used to calculate ECON climb and cruise speeds and if you used a CI of 100 it should't be a problem.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpg

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>SO is their something wrong with the pmdg code, because the>fmc never lets me above 350 initially.I would love to try this on my NG but I don't have it installed right now. I have the 744 and 744F installed at this time and will have to re-install them if I re-install the NG.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpg

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