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metzgergva

Trim settings on take-off changed with new version

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Hi,hope it is OK to put this as a topic again as with the other post there are some user issues.I flew the original FSX version for 2 month and the trim settings given from the TO page gave excellent handling during rotation and initial climb. Now having flown the FS9 and FSX version including the update with different loadings, that is not the case anymore. Following the recomended data, the plane rotates on a tiny move on the yoke and to fly FMS climb out speed needs immediate forward trimming.I do take care of having fuelling completed and let CoG calculation refresh to actual load.From what my knowledge of TO trim is that it is mostly V2+10 or even V2+20 which is is the speed you trim for and that is included in the FMS calculation. So the original FSX version was spot on, the latest FS9/FSX version is unfortunately different. Would be great if you could correct that in a future update.Best!Alexander M. Metzger

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Hi,hope it is OK to put this as a topic again as with the other post there are some user issues.I flew the original FSX version for 2 month and the trim settings given from the TO page gave excellent handling during rotation and initial climb. Now having flown the FS9 and FSX version including the update with different loadings, that is not the case anymore. Following the recomended data, the plane rotates on a tiny move on the yoke and to fly FMS climb out speed needs immediate forward trimming.I do take care of having fuelling completed and let CoG calculation refresh to actual load.From what my knowledge of TO trim is that it is mostly V2+10 or even V2+20 which is is the speed you trim for and that is included in the FMS calculation. So the original FSX version was spot on, the latest FS9/FSX version is unfortunately different. Would be great if you could correct that in a future update.Best!Alexander M. Metzger
I notice a similar behaviour before the update the weights were lower for same chosen load in the load manager (eg full was around 177 tons ZFW and now 195 tons ZFW) and obviously the trim settings cacluated is different. Before at VR you had to 'pull' the AC into the air which it rotated at a nice steady rate, now I notice even before VR just after V1 the plane starts to get 'light', like it it almost lifts off the ground by itself and when you pull back the rotation rate is much quicker for the same amount of stick pull.Jay V.

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It isn't all that surprising though as the STAB numbers have pretty much doubled to what they used to be before the update, whether this has anything to do with the new H distribution setting in the load manager I do not know. I use Kilo weight units I don't know if this is relevant to any testing you may wish to do.

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Yeah I've started using much lower Trim values then given by the MCDU not very realistic but neither is no Performance tables Flex numbers etc etc etc etc .... great systems simulator tho lol :(

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I must admit I reran the FS9 tutorial last night with all the right weights/figures and as stated got the stab trim as 7.6 as in the tutorial and agreed on the to/appr page and she shot up in the air I had to really push the yoke forward to stop it going vertical. It still went to protection mode even then.I'm now setting the trim so it's just inside the green band.... works ok then. Does seem a very sprightly bird compared to before the adjustment.Not moaning or nitpicking. I haven't tried it on the L setting so can't compare yet lol.John Ellison

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I'm on a short hop OBBI - OKBK aircraft gave me a trim setting of 7.2 I gave her 4.2 and a the max flex temp of 70c and she rotated perfectly, no frantic post rotation trimming needed to follow the FD. Her pitch on climb is so steep but I guess it's like that on the real thing, it would scare the sh*t out of me in real life!I always fly her with max cargo and havn't done a longhaul haul with a Heavy fuel load but she reminds me of the rare occasions I would perform a Max thrust T/O with a empty 744FRob

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Has the issue with the Stab. trim been resolved or commented on my the PMDG team. This is a very important issue and I'm awaiting somebody from PMDG to address this seemingly unresolved anomaly before I initiate a purchase of this software. Regards,jack

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It shouldn't deter you from buying the product, Just follow some of the suggestions on the thread.Rob

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Same problem with FSX version as well... I'm gonna set trim to 'just' in green band for now and still be prepared. H or L makes no difference, still a rocket ship lol.Sure it'll ne looed into though, probably just a tweak required, ok before the patch, so no big deal.At least aware of it now lol.John Ellison

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I also have a rocket takeoff in FS9. To follow the FD bars I have to push my yoke.But since I'm not a real life MD-11 captain and I heard this bird is a rocket, I thought it is normal.Now I just don't know.Best regards,Rafal

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I also have a rocket takeoff in FS9. To follow the FD bars I have to push my yoke.But since I'm not a real life MD-11 captain and I heard this bird is a rocket, I thought it is normal.Now I just don't know.Best regards,Rafal
I also have a rocket takeoff in FS9. To follow the FD bars I have to push my yoke.But since I'm not a real life MD-11 captain and I heard this bird is a rocket, I thought it is normal.Now I just don't know.Best regards,Rafal
Cudley1956 quotes: "Sure it'll ne looed into though, probably just a tweak required, ok before the patch, so no big deal." I'm not understanding this or am I to assume that the trim anomaly was ok before the patch, but NOT OK after the patch !!!!!Would someone from the PMDG team care to respond to this supposed anomaly???Much appreciated as I am a little confused over this very important systems issue...Regards again,jack

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One of the beta members (downsc) responded to my post and stated he never has had to push the nose down on takeoff so I take it I or we are doing something incorrectly. I will continue to practice takeoffs until I find my issue. I even bought a new controller just to do away with it being my old controller but to no avail.Thanks,Sean Green

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I never need to push the nose down but I do need to be very careful pulling the plane up on rotation, at V1 the plane already wants to lift off on it's own since the patch. Before the patch the aircraft felt normal.Jay V

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Can you confirm that this occurs after the update to both the FSX and FS9 versions?I am especially interested to hear if it applies to the FSX version. Please confirm that if you are absolutely sure ("I think it might be a bit different.." won't help).

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Can you confirm that this occurs after the update to both the FSX and FS9 versions?I am especially interested to hear if it applies to the FSX version. Please confirm that if you are absolutely sure ("I think it might be a bit different.." won't help).
Definitely applies to me with the FSX version (I don't have FS9 version) after the SP1 update, take off behaviour is much different as I stated in my last few posts in this thread. If you would like me to do any testing or screen shots just ask :)Jay V

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The FSX version is definitely suffering from this problem, and the STAB readings are now exactly double what they were before. I remember the STAB reading from a regular flight I used early on with the same payload and fuel weight. The reading used to be 3.8 and now in the new version it is 7.6 and she takes off like a rocket compared to the way she used to do. The first time I tried the new version I rotated the exact same way as previous on many flights and I ended up having to input an appreciable amount of forward pressure on the stick to keep the FD centred.

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The FSX version is definitely suffering from this problem, and the STAB readings are now exactly double what they were before. I remember the STAB reading from a regular flight I used early on with the same payload and fuel weight. The reading used to be 3.8 and now in the new version it is 7.6 and she takes off like a rocket compared to the way she used to do. The first time I tried the new version I rotated the exact same way as previous on many flights and I ended up having to input an appreciable amount of forward pressure on the stick to keep the FD centred.
Andy,STAB reading (I assume you mean on the TAKE OFF MCDU page) does not depend on payload and fuel weight. It depends only on flaps setting (as entered in the TAKE-OFF page) and TOCG (take-off center of gravity). TOCG will be lower (more forward CG) after the update, because of the way the load manager is now doing the payload distribution when you press the 1/3, 2/3 or random buttons (actually it is the ZFWCG that is lower and this makes the TOCG also lower). Still this is no reason for the situation you describe to occur. With a more forward CG a higher STAB TRIM is indeed required and the aircraft should behave equally well. We will investigate this further.

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I use 22 degrees flap exclusively along with the same seating arrangement and always fully loaded passengers and cargo, just for your further information.

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My guess is (and could be completely wrong), since the update with the same load used in the load manager (not using H distrib) the aircraft is almost 20 tons heavier, full load prior SP1 roughly 177tons, 194 tons after (ZFW). The V speeds have increased with the added ZFW though it appears to me the plane still 'feels' like it physically is the 177tons ZFW but is configured for a takeoff of 194 ZFW.Jay V

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Can you confirm that this occurs after the update to both the FSX and FS9 versions?I am especially interested to hear if it applies to the FSX version. Please confirm that if you are absolutely sure ("I think it might be a bit different.." won't help).
Michael,FSX version 51:During the first T/O segment (about to 1500ft, maybe higher, not sure) LSAS AutoTrim is not available anymore with the 'new' STAB settings.If rotating to a wrong pitch attitude on purpose, correction by applying a pitch correction does only help temporarily, as the stabilizer is not retrimmed.Think the Stab. angle and required Elevator commands are mis-aligned by more than 5 degrees.Have to recheck the FS9 version to be sure it's the same there.Thanks for investigating, hope this helps.Regards,Harry

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