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Guest lalo lolo1

Nose Up Attitude - Can It be altered ?

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It seems that many jet aircraft (airliners) I download and install have a tendency to fly with a decided "nose up" attitude. This nose up problem only becomes more pronounced when making a landing.I know this can be changed using the pitch/trim wheel but was wondering if there was anything in the aircraft.cfg or .air file that could be changed (or at least experimented with) that would allow the aircraft to fly more level in it's default mode.Any tips appreciated.

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Guest danowat

Be aware that airliners by design have a nose up attitude in cruise, dpeending on the airliner maybe 3-5deg.Also, if you are experiancing to high nose up on landing you may not be properly configured for landing, your Vref may be too low for your flap setting and weight.You can try changing this value, in the aircraft.cfg file{flight_tuning}cruise_lift_scalar=1.000This will decrease the nose up in cruise, but to change the landing attitude may require more indepth FDE editing, but I would suggest taking a look at your approach speed and flap settingsDan.

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Thanks DanI will try that. Noticed a comment regarding weight. Can you expand on that just a bit? If the tanks are basically at right angles to the body (i.e. wing) how would that affect the nose to tail relationship?I appreciate our help and ideas.

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Guest danowat

Its all to do with the speed and flap setting, the heavier the plane the faster the Vref needs to be for a given flap setting, which in turn determines the aircrafts pitch.Dan.

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it's all in aerodynamics ..the lower the IAS, the higher the angle of attackthe higher the IAS, the lower the angle of attackLift = 1/2 rho x V

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Guest RonB49

Going one step further:>use of slats and flaps will allow you to lower the angle of attackBecause slats and flaps increase S and allow you to decrease CI.R-

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Guest Divergent Phugoid

Ah. Not really. Fowler or Zap flaps do increase wing area and so will have an effect. Flaps primarily lower the nose because they increase the AoA and hence the CL.

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Guest RotorRick

Also, don't try to land with nearly full fuel load: you are too heavy. In the real world, if an airplane has to make an emergency landing, if they have substantial fuel loads, they will quickly dump it.Too much weight:-higher landing speed required-too much stress on landing gear-high chance of blowing multiple tires on landing-loss of job as airline pilot (maybe)

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David,> Noticed a comment regarding weight. Can you>expand on that just a bit? If the tanks are basically at>right angles to the body (i.e. wing) how would that affect the>nose to tail relationship? Most of the jet passenger aircraft have swept back wings (approx 35 degrees) thus the tanks are NOT just at right angles but indeed have a substantial fore/aft relationship to the centre of gravity. Also the B747-400 has optional fuel tanks in the horizontal stabilizer. Cheers,Roger

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I have had a great deal of success changing the pitch attitude of various aircraft by modifying only the cruise lift scalar field. It's usually set at 1.00 and if the nose is too high at cruise and during approach (some models approach at +5 deg which is too high on many jet a/c), I've usually increased the value to somewhere between 1.25 and 1.66. It depends on the model. I've not had to change the flap scalars and never will because that starts triggering too many variables.One thing to be aware of is that when you change the cruise scalar, the subsequent change of aircraft pitch affects N1 and fuel flow because you change the profile of the aircraft facing the relative wind. It's not a huge diff but on a 12 hour flight, it can make a somewhat noticeable difference in fuel consumption.JS

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Thank you - That is what I had been looking for - someone else had suggested playing with that value but gave no indication what to try.Thanks once again.

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Try to change the cruise lift scalar in gradations of 0.15 at a time. You can do it on the fly as well (no pun intended!). For example, get into a 747-400 that you like and start flying.Open up the aircraft.cfg file for that a/c while in the air. Change the cruise lift scalar by 0.15, i.e., make it 1.15. Click on SAVE. Then return to FS2004 and reload the a/c that you are already flying by going to the aircraft selection menu. Click on the a/c to reload it. Your 747 will be reloaded with the NEW cruise lift scalar value you just edited.Save the old or default value by typing "//" AFTER the new scalar value; this will ensure that FS does NOT "read" the original value and Windows will not delete it.I did this dozens of times and found the "Sweet spot" on 10 major airliners I love. They fly, cruise, and approach and land beautifully and MUCH better than the original versions. I've also modified the N1 and fuel flow factors but that's another story (or post)!Hope this helps. Good luck!JS

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Another thing to consider is that flaps also change the chord of the wing relative to the longitudenal axis. This makes the nose angle down more , but have the same angle of attack.----------------------------------------------------------------John S. MorganReal World: KGEG, UND Aerospace Spokane Satillite, Private 130+ hrs.Virtual: MSFS 2004"There is a feeling about an airport that no other piece of ground can have. No matter what the name of the country on whose land it lies, an airport is a place you can see and touch that leads to a reality that can only be thought and felt." - The Bridge Across Forever: A Love Story by Richard Bach


John Morgan

 

"There is a feeling about an airport that no other piece of ground can have. No matter what the name of the country on whose land it lies, an airport is a place you can see and touch that leads to a reality that can only be thought and felt." - The Bridge Across Forever: A Love Story by Richard Bach

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Guest lalo lolo1

Just use Shift+Enter and Shift+Backspace to change you view. Try this and for sure you'll find the pitching doesn't bother you anymore.It is very normal that any jetliner pitches while cruising, and for sure when landing you will always want to touch the ground with the main gear first, and never with the nose gear.The problem you are talking about, I think, is the poor visibility you get when the AC pitches maybe only 3 or 4 degrees.This is due to a bad combination of eyepoint in the aircraft.cfg combined with VIEW settings in the panel.cfg. Just use the tip in the first two lines. You can pitch 12 degrees and still see the Rwy with no problem.If the problem is that the AC pitches badly even with full flaps, low fuel and going fast, then increase the pitch value in the flaps parameters of the aircraft.cfg file. Try different numbers until reaching the desired effect.Hope this helps,Leo

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