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Hello,I have been flying Fly!2 for a couple of months now. Generally I am very impressed by Fly!2, the instrument panels, the scenery editor and lots of stuff. I have bought PMDG's Boeing 777. Am I impressed?! Yes! The flight management computer is very well done and it is thrilling to get the feeling of flying a real, modern glass cockpit heavy airliner.There is however one thing that has made me slightly dissapointed and that is the flight characteristics, especially the roll rate. I use CH USB yoke and pedals when I fly Fly!2 and I have calibrated the controls several times. I have also done some experimenting with different exponential settings for roll, pitch and rudder. But whatever I do the roll rate remains extremely slow. And that goes for all planes I have tried, so it must be a flaw in Fly!2 and not in PMDG's addon. Even if I move the yoke fully to the right, the planes roll slowly, slowly, slowly. It takes hours (well not exactly but it feels that way) to go from 30 degrees right bank to 30 degrees left bank. To be honest, in bad weather with gusty side wind it would be absolutely impossible to land any of the planes I have tried. I have a friend, who is now retired, but who was a DC-9 Captain in SAS (Scandinavian Airlines System) for many years. After flying around in Fly!2 and doing some take offs and landings, he came to the same conclusion as I did, and says that a plane must have much more "aileron authority" than is the case in Fly!2.I have not been able to find something about this in the forum. Is there anything that could be done regarding this? Some data file that could be changed? I mean, in cyberspace it should be very easy to get any roll rate, even 360 degrees per second, so why not a realistic roll rate. I don't know of any way of changing the sensitivity of my flight controls (more than the exponential, which I have set to 100). I use the same controls in X-Plane, and in that simulator the roll rate is perfectly realistic.Any suggestions?Thanks!/Zorropisa

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Guest tonyc

It's interesting that you should say that about the roll rate. But please check the "option" under the aircraft menu and play with the slides. There's a driver ( I don't know if it's for usb as well) that allows configuration of the x,y and z axis relative to yoke travel.tony

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Hello Tony,Thanks for replying. I have checked the option under the aircraft menu and tested different settings of the slides to the right (the left hand slides only affect keyboard inputs). Whatever setting I choose, the roll rate is far, far to slow for making a safe side wind landing in gusty conditions. I tested the PMDG's 777 and from 40 degrees left bank to 40 degrees right bank angle it takes more than 10 seconds with full yoke deflections. It should only take a few seconds even for a heavy airliner according to my friend, who has been flying heavies for almost 30 years.And the problem could hardly be in my joy stick calibration. When I use axis test in Fly!2 the response is perfect. Full joystick deflection gives max deflection in the calibration window.There must be a systematic flaw in Fly!2. A pity as so much else is extremely good. I wonder if there could be some data file that could be changed. When setting up the different parameters for a plane, it should be possible to get a much faster roll rate through some suitable parameter setting./Zorropisa

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Guest tonyc

send me your e-mail. I send you a file that might help.tony

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Hello Tony,Thanks for the file. Sadly it did not work with Windows XP. And the problem, by the way, is not with the stick sensitivity but with the flight model. So I sat down a few hours and read Rob Young's instructions about how to tweak the plane data files. And after some experimenting I got the roll rate I wanted.A Boeing 767 has a roll rate of 10 degrees per second with flaps 30 and 15 degrees per second in clean configuration. That is, a clean 767 should roll from 30 degrees left bank to 30 degrees right bank in 4 seconds. I think a 777 ought to have about the same roll rate. When I timed the PMDG's 777 this took about 10 seconds. It would be very dangerous to try a side wind landing in turbulent conditions with such roll rate. After increasing a parameter in the .wng file I got it right.Thanks for trying to help.rgdsZorropisa

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Guest tonyc

Gee, that's great. I am glad you persevered and got it to work. tony

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Hi Zorropisa!Since I use Fly!II and X-plane as well, I'm also concerned about this issue, where the two simulators differ so much (in fact, it's THE point where they differ!). I'm not a real pilot, but as you point out, the numbers are usually available and we can compare with the real thing. I also believe each one have some very strong points regarding aerodynamics realism.X-plane is quite a reference in that matter, although I can't have total confidence with it, since some big issues where only solved in version 6. For example, I have been amazed that it didn't take torque and gyroscopic effect into account before this version!!! In the contrary, Fly! in the beginning totally overdid these effects (this has been fixed since then).Maybe we can see a similar issue here. I noticed Fly!II commands have a big inertia. It takes maybe half a second before the device input starts to move the plane. Then, the plane's inertia itself plays its role until we reach the full roll rate. I don't know how engineers calculate the rate, wether from right to left 30

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Hello Pascal,I suppose you have Podview installed (in the Tools folder in Fly! 2 folder). Let's say that you want to tweak roll rate of PMDG:s 777-200. You double click on the PMDG777BASE211.pod in the aircraft folder. Podview will open this and you will see all files (hundreds of them). Find a file called PMDG777200.WNG. Use "Extract selected files" in the Podview File menu. Open the extracted file with Wordpad (it is an ordinary text file). Look for "Left Wing/Aileron section Data". About ten lines below or so you will find "Lift vs Flap Angle Data" and under there and then 3.15 (for other planes it could be another value). This parameter controls the left wing aileron authority. I increased it to 4.15. Then go to "Right Wing/Aileron section Data" and do the same thing with the right aileron (do as above), but there you should set the parameter to -4.15 (or whatever you choose).One problem is that changing one parameter might cause a lot of side effects. I have only tested my tweaked 777 shortly. It could be that changing this parameter influences other flight characteristics in a negative way, something that might become obvious later.An other way to change roll rate can be done in the PMDG777200.SVH file (you find it in the same pod-file). There you find "momentOfInertia" and then three numbers which refer to pitch inertia, yaw inertia and bank inertia. You could experiment with the last number to make a plane more responsive around the roll axis.When you have saved you changes, you create a folder called "World" in the Fly! 2 folder (if you don't have it already). Place the changed file/files in this folder. Check that in the Fly.ini file the line "SEARCHPODFILESFIRST=0". If this line is set to 1, Fly will not use the files in the World folder, it must be set to 0. If you want to revert to the original plane data, just drag the respective files out of the World folder.If you want to do some more serious tweaking I recommend that you read Fly! Tutorial - Tweaking the Flight Models" by Rob Young. You find it in Avsim file library. Rob's tutorial is written for Fly! and in Fly!2 there is a different file structure in the airplane pod-files. In Fly! all flight characteristics are in one file ".SVH". Now, only some of the data is there, and there are separate files for other stuff, i.e. everything about the wings is in a ".WNG" file, etc.Do you still fly X-Plane? I have made an MD-80 for X-Plane 6.0 (an older version is uploaded to Avsim) and spent many hours adjusting the flight model. I have a friend who has been flying DC-9 (very close to MD-80) who has tested my plane and who is very satisfied.rgdsZorropisa

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>A Boeing 767 has a roll rate of 10 degrees per second with>flaps 30 and 15 degrees per second in clean configuration.This sounds like a very high roll rate. When I get home tonight I will measure it on the 767PIC - developed by a 767 pilot and widely acclaimed to have best flight model around. And apparently it is specially good in roll rate. So I will verify it tonight and post it here. But 10 deg per seconds (or even 15) sounds high to me from my vast flying experience with the 767PIC. There is a Capt. BBall (NWA) hanging around on the PIC forum - you may ask him. If 767 can roll that fast surely 757 would be as fast.Michael J.

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Hello Michael,I got the roll rate data after a search on the Internet. I don't remember where I found these figures, because I didn't save the document (I searched for an hour until I found some data for roll rate -- I did not find data for the 777 though), but it was some kind of data page for 768. It looked quite official. I am sure that with 30 degrees flaps it was 10 degrees per second with a 768 because I wrote this down.And in very turbulent side wind you need a lot of aileron authority to make a safe landing. I have a friend, who has been flying DC-9 for SAS for many years (it was he who pointed out to me that the roll rate of the PMDG 777 was far too slow). He told me that the max side wind component for a DC-9 is 38 knots (depending upon model)! Very impressive. But the DC-9 was known (or is known, some are still flying -- SAS sold their last just a year ago or so) for its unusually high aileron authority. rgdsZorropisa

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