>>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

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.Michael J.http://www.precisionmanuals.com/images/for...argo_hauler.gifhttp://sales.hifisim.com/pub-download/asv6-banner-beta.jpg

>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

>By your responses to me I kind of doubt your last sentence>;-)John,I highly respect you, trust me ;)Michael J.http://www.precisionmanuals.com/images/for...argo_hauler.gifhttp://sales.hifisim.com/pub-download/asv6-banner-beta.jpg

>>>By your responses to me I kind of doubt your last sentence>>;-)>>John,>>I highly respect you, trust me ;)>>Michael J.:-beerchugCheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpg

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

>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.

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.

>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

>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

>SO is their something wrong with the pmdg code, because the>fmc never lets me above 350 initially.Can you post your Gross weight that you have for this flight and I'll check in my manuals? Pretty hard to tell you what the altitude should be without your weights.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpg

G'Day JohnIs the MAX Diff 9.1? Didnt know they got that high, lol The BAe 146s I work on go to about 7-8.

>G'Day John>>Is the MAX Diff 9.1? Didnt know they got that high, lol The>BAe 146s I work on go to about 7-8.Hi Ryan,Yup, 9.1. Boeing is seeking approval on the BBJ2 to an even higher Diff. Press (12.0 psi) to allow cruise altitudes as high as FL450 (8,000 ft cabin) but with a reduced fatigue life of 60,000 cycles or to remain at FL410 with a 6,500 ft cabin altitude.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpg

The recently certified SJ30 has a pressure differential of 12 psi. The highest certified I believe.Wes

>The recently certified SJ30 has a pressure differential of 12>psi. The highest certified I believe.>>WesThat's getting to be some high diff. pressures. Even Concorde had a max diff. of 11.2 psi.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpg