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Andrea1

Very strange N1 on approach

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Hi to all,I can't know if the ground effect during approach of FSX is corrected not being a real pilot (I know only that I feel myself more confortable with the real fixed base training sim that I use, being there the flare really more simpler, than in FSX where until now I've never succeded in finding the "real feel" on landing..) but I noted a think that appears to me very strange after SP1: I was at bout 57 tons (53 + 4 of fuel) approach cinfig: flaps 30, Vref 138+5=143 kts (I got short distance config) and during approach (ILS 35R LIMC and no weather conditions, ISA only no wind) I could read N1= 43% (stable not during i.e. deceleration) ! It's seems to me a bit too low for approach, in the real sim I can't remember exactly but there we've never gone less than 50% (it could be 54-56%) it seems to me too low drag anyway..(but I can't know if it could be due to the "short field version" particular aerodynamics)...Any idea?CiaoAndrea Buono

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An approach idle of 43 % N1 is very realistic for a 737ng !!Sounds like that FTD needs a bit of tweaking...........as they usually do.Fred.


Frederic Steiner.

B7382.jpg

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Hi,Yes you're right but I was not an "approach idle" it'd mantained 43% during all the last part of the approach...ByeAndrea

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Hi to all,I can't know if the ground effect during approach of FSX is corrected not being a real pilot (I know only that I feel myself more confortable with the real fixed base training sim that I use, being there the flare really more simpler, than in FSX where until now I've never succeded in finding the "real feel" on landing..) but I noted a think that appears to me very strange after SP1: I was at bout 57 tons (53 + 4 of fuel) approach cinfig: flaps 30, Vref 138+5=143 kts (I got short distance config) and during approach (ILS 35R LIMC and no weather conditions, ISA only no wind) I could read N1= 43% (stable not during i.e. deceleration) ! It's seems to me a bit too low for approach, in the real sim I can't remember exactly but there we've never gone less than 50% (it could be 54-56%) it seems to me too low drag anyway..(but I can't know if it could be due to the "short field version" particular aerodynamics)...Any idea?CiaoAndrea Buono
Did you do a clean install of sp1? I recall this happening to me when I installed hotfix 4, but it didn't happen to me on the one flight I've done after sp1.

Boeing777_Banner_Pilot.jpgsig_TheBusIveBeenWaitingFor.jpg

Alfredo Terrero

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Hi to all,I can't know if the ground effect during approach of FSX is corrected not being a real pilot (I know only that I feel myself more confortable with the real fixed base training sim that I use, being there the flare really more simpler, than in FSX where until now I've never succeded in finding the "real feel" on landing..) but I noted a think that appears to me very strange after SP1: I was at bout 57 tons (53 + 4 of fuel) approach cinfig: flaps 30, Vref 138+5=143 kts (I got short distance config) and during approach (ILS 35R LIMC and no weather conditions, ISA only no wind) I could read N1= 43% (stable not during i.e. deceleration) ! It's seems to me a bit too low for approach, in the real sim I can't remember exactly but there we've never gone less than 50% (it could be 54-56%) it seems to me too low drag anyway..(but I can't know if it could be due to the "short field version" particular aerodynamics)...Any idea?CiaoAndrea Buono
That seems a bit low to me; you should be seeing around 55% N1 for a Flap 30 approach.Cheers,Doug

Doug Boynton

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Hi Doug,in fact I agree it's a bit low to me too...in real sim was about 55%...Best RegardsAndrea

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Don't forget, fsx is not a 'real' sim - you can't really compare it to anything for training. Otherwise we'd all be qualified big jet pilots, which of course is nonsense.


Chris Farrell

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Don't forget, fsx is not a 'real' sim - you can't really compare it to anything for training. Otherwise we'd all be qualified big jet pilots, which of course is nonsense.
There will always be shortcomings in these programmes but please see this extract from the 'Introduction' manual:
“Simulation” should mean nothing short of incredible depth, detail and feature richness that allows for the proper application of real-world operating procedures and techniques without offering excuses as to why parts of the airplane behave differently than what is described in the flight manual.
“Simulation” means that when you engage the autopilot and put the airplane into LNAV/VNAV, it should behave like it would if you were actually flying the airplane. This means that it behaves not just in easy to manage climbs and descents, but it reacts appropriately when you punish the airplane with rapid changes and demands near the limits of the airplane’s capabilities.
“Simulation” shouldn’t leave you saying: “Well… it is just a flight-sim product.”
Cheers,
Doug

Doug Boynton

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Problably I've to master a bit better the NGX, problably I can't remember the right numbers (N1 in this case) it's not a product problem also the "old" PMDG 737 had, for the most part of flight, "right numbers" (according with CAL 737 FCOM performance tables) and NGX should be also better (you could verify that also i.e. during ground idle: now fuel flow and EGT match the real numbers (ISA MSL about 300 kg/h and 370-400 EGT) and engine starting numbers are now perfect) and, during the last session I've flown in the real sim, I've used flaps 40 for approach so problably I confused the numbers...anyway I'm practaising a lot of langings to master them, I've to have a lot of training, 'cause until now I find the real sim easier to flare...(maybe 'cause of real yoke vs. joystick)Best RegardsAndrea Buono

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Problably I've to master a bit better the NGX, problably I can't remember the right numbers (N1 in this case) it's not a product problem also the "old" PMDG 737 had, for the most part of flight, "right numbers" (according with CAL 737 FCOM performance tables) and NGX should be also better (you could verify that also i.e. during ground idle: now fuel flow and EGT match the real numbers (ISA MSL about 300 kg/h and 370-400 EGT) and engine starting numbers are now perfect) and, during the last session I've flown in the real sim, I've used flaps 40 for approach so problably I confused the numbers...anyway I'm practaising a lot of langings to master them, I've to have a lot of training, 'cause until now I find the real sim easier to flare...(maybe 'cause of real yoke vs. joystick)Best RegardsAndrea Buono
A Flap 40 approach produces more drag hence more power is required: in this case you should see approx 60% N1Doug

Doug Boynton

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After SP1 i did following observations regarding flaps 30,40 (app on ILS) pitch & N1 on 800WL:GW 58.3, flaps 30, Vref+5, pitch 2.5 deg, N1 43% N1GW 58.3, flaps 40, Vref+5, pitch 0.5 deg, N1 63% N1PMDG fixed flaps 30(but got the N1 wrong) & nothing was done for the pitch setting on flaps 40?????There's a way to fix this, as a solution for this problem existed(before SP1) hare on the forum(credits to martin-w ), now my 800WL behaves closer to mr Boeing manuals after SP1:)))Remember to make backups if you are not satisfied with this tweak.What I did: from the 1st install version I saved the AIRFILES & Aircraft cfg for all versions in a folder.In the saved folder for 800WL: in the flaps.0 section of the aircraft cfg change lift_scalar = 0.8 & save.Apply SP1. Replace the airfile & aircraft cfg. in the new version, with the (old saved) airfile & aircraft cfg.In old aircraft cfg: copy [Flaps.0][Flaps.1][Flaps.2] sections, & replace them in to the new aircraft cfg.With this tweak I get the correct pitch & N1 for flaps 30,40 & no floating during landing:) I don't know how this tweak affects other aspects of the flight envelope after SP1, I tested it yesterday only on approaches. If you find anything wrong with this tweak please let me now.


Kind regards
R.G

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My observations after SP1 are a bit different. From my QRH B737-800 WL Chapter "Flight with Unreliable Airspeed" I can read:60 tons Flaps 30° Vref30+10 Pitch 1° N1 56%60 tons Flaps 40° Vref40+10 Pitch -0.5° N1 62%On the attached screens with stable conditions, ISA temp and clear weather:60 tons Flaps 30° Vref30+10 Pitch 1° N1 56.5%60 tons Flaps 40° Vref40+10 Pitch -0.5° N1 64.1%So the drag or the engine parameter is slightly higher with flaps 40.I find this very accurate.


Happy flying!
Alexander M. Metzger

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