Hi guys,I had a chance to talk with a B734/B738 First officer last week, he have FS2002 and DF734 on his laptop. I asked his oppinion on DF734 Flight dynamics and here is what I understand from conversation..1 - FS Aircraft or FS itself have too much drag. He said there is no chance to slow down while descending unless using speedbrakes. For this reason 737s needs very good descend planning, especialliy NG series.2 - Yaw dampers, you know the rest.. PMDG, any chance to find a solution?3 - Pitch sensivity, He said 737 is very pitch sensetive airplane but it's stable on trim. He found most FS aircraf unstable even in correctly trimmed position.

Bozhan-we pride ourselves in having one of the best FS Flight Dynamics experts in the world, with a Ph.D. in Fluid Dynamics, etc. etc. (the guy's modest, so I won't go all out on his talents).Needless to say - the numbers are pretty darn close to reality in all aspects of flying... (he was upset a couple days ago that his N1 setting at FL390 was 0.5% off the real thing... go figure ;-) )

I beg to differ with all his points. I fly many aircraft that are to "slippy" on descent and maybe your friend should try PIC 767 and tell me if she does not descend correctly! Trim is a varible so this is subjective. Not the yaw damper ahhhhhhhhhhhhhhhhhhhhhhhhhhhhhh....LOLBest Wishes, Randy J. Smith[h5]San Jose Ca[/h5][h3]" A little learning is a dangerous thing"[/h3]AMD XP 2100 |MUNCHKIN 512 DDR RAM |ECS[/b ][i] K7S5A MB[/i] |GF3 64 MEG |WIN XP PRO |MITSUBISHI DIAMOND PLUS 91 19"

Lefteris,What I found useful to test the dynamics of a flt model are the Blocked airspeed indicator Charts, to confirm various Pitch+power=performance.[http://81.68.225.132/marcbrodbeck/docs/PITCHWR.pdf]Cheers, Marc Brodbeck

It's good to know we are in safe hands :-) As for the 767, I just turn of the both yaw dampers and clear the eicas via cancel. Another way is overpower the rudder by 12 times in aircraft cfg, then you can have both yaw damper and manuel rudder control same time but this time it's tending to turn left in level flight so I don't use it. Damn 767, I supposed to talk about 737 here :-) Thanks for understanding PMDG.

>(he was upset a couple >days ago that his N1 setting at FL390 was 0.5% off the real >thing... go figure ;-) ) If that is true, then that is commitment!

Dear Marc,>What I found useful to test the dynamics of a flt model are >the Blocked airspeed indicator Charts, to confirm various >Pitch+power=performance. >>[http://81.68.225.132/marcbrodbeck/docs/PITCHWR.pdf] The next page (missing from that pdf document you mentioned) contains pitch/N1 numbers for approach [flaps 15/30/40]. The next-next page (also missing) contains data for cruise N1/fuel flow figures.The next-next-next page contains blah blah blahI hope this one answers your question of whether we consult original manuals and other documents (not available to the general public) regarding performance and flight dynamics. All numbers are within FAA official approval percentages (5% or errr... much less) -- the latter should also tell you guys something.Regarding flight models in general only a handful come even close to real world performance --- even some praised by reviewers, us customers and pretty much everybody. BUT, BUT you need the manual to find out. Handling by the way is a completely different thing from "numbers"/performance. May be I'll come back on that subject some time as a "customer" and/or an aerodynamicist rather than a developer.Best Regards,VangelisE. M. VaosPrecision Manuals Development Group

people also fail to realise that if you want real.. go learn to fly.. Reanacting the RW with a program is a very hard task, so to see such a wonderfully done product be argued about due to the fact he or she was .5% of the RW engine ratio's or what not.. is quite redundant. I currently have 30hours logged in a Cessna 172, I can tell you first hand (as some of you can too possibly) that no product comes remotely close to a simple plan such as that of a Cessna. That RW 737 pilot that says that FS is quite draggish feeling. I agree.. the flight dynamics are most likely imposible to re-create seeing as one simmer uses a different setting( sensitivity etc..) to another, such as the code writter. :-wave"... AND I'M PROUD TO BE AN AMERICAN!"[b/]http://forums.avsim.net/user_files/54951.jpg You rock my world Lauren! :-hah

"Trim is a varible so this is subjective."On the subject of trim... here's a question for the real NG pilots....With an engine out (and A/P engaged, if regulations allow), does the aircraft fly wings level with no rudder trim? (Or is there a constant roll correction?) The wings in PMDG seem to stay level whereas other sims (of other Boeings) seem to fly one wing down.Is PMDG modelled this way because it has no rudder trim knob (that I can find) or is this normal NG behaviour?Thanks.Cheers.Ian.

Not to mention different types of controls, joysticks and yokes with different sensitivities! Different weather addons, different FSUIPC configs, different FS (2K or COF) configs, different MS Win configs, different video drivers, on and on and on...So one must ask a question here

>"Trim is a varible so this is subjective.">>On the subject of trim... here's a question for the real NG>pilots....>>With an engine out (and A/P engaged, if regulations allow),>does the aircraft fly wings level with no rudder trim? Yes. Aileron down - you just trim the rudder until the control column is level.

Thanks, Andrew.Perhaps in the -800/-900? ;-)Cheers.Ian.

... that there is something wrong about the yaw axis MOI, or coupled MOI because, for instance, when you kick the rudder to align with rw centerline heading during a crosswind approach, the aircraft slides sideways (while still flying) towards upwind.Say you're approaching Lisbon's LPPT rw 03 (29 degrees MAG) and the wind is blowing at 15Knots from 310. During your manual/coupled approach your aircraft is crabbed towards the wind, and just before touchdown you uncrab by using right rudder pedal to align with rw centerline. Now, as one does such a thing in a real airplane, the air mass will push it downwind, and that is why pilots uncrab while lowering the upwind wing.On many aircraft in MSFS, including PMDG's 737NG, the aircraft will (strangely ???) slide sideways towards the wind (upwind), so, in this example, while it is aligned with the rw centerline it will move sideways towards the left side of the rw, wich is a perfectly unexpected effect.Regarding the simulation of Yaw Dampers, the only two simulators that I know do modell it accurately are AS2 and PS1... :-)

A PMDG user did fix that problem, but was refused by PMDG to share the file with anyone. I one of the lucky guys that got it before PMDG refused distribution, so I'm happy flying manual crosswindlandings :)Jan Roar Rod

I preffer to wait for a fix from PMDG themselves than starting to tweak the AIR or CFG file. There are so manay many interactions between parameters, and certainly their own implementation of the AFS that I fear to spoil some other more important item....Using MSFS is a compromisse between scenery sugar and flight/systems modelling. I think PMDG has reached the absolute "maxima" in what can be done with MSFS's core limitations.