I recently switched from Flight Gear to FSX. The Flight gear community is very passionate about the realism of their flight model, but because it is open source there are numerouse bugs and performance issues, many of which have to be fixed with coding that is tedious and I am not very good at it.

 

Mostly I fly GA aircraft like the Cesna 172. In Flight Gear, if I land too hard the aircraft wil bounce off the runway and nose up making for a very uncontrolled landing, (generally ending up on the nose of the aircraft once I come to a complete stop--often NOT in front of the terminal building!) Therefore, the landing approach has to be nearly perfect to be successful in FG.

 

The contrast in FSX is that even with the realism settings turned all the way up this does not happen. I can land a Cesna 172 a bit too hard and the aircraft just squats down on the runway. Also, taxiing in a crosswind is much easier in FSX than in Flight Gear. I have had the plane pushed around all over the place in a 10 kt crosswind running in Flight Gear, but hardly at all in a 16 kt cross wind running in the FSX environment. Overall, handling a Cesna 172 and landing successfully seems much easier in FSX than in Flight Gear.

 

Can anyone tell me if this is a lack of realism in the FSX model, or is the Flight Gear model over sensitive in an attempt to "prove" their superiority (ie, if only the best can do it successfully then our program must be better than the mass-market program)?

 

RDS

Also, taxiing in a crosswind is much easier in FSX than in Flight Gear. I have had the plane pushed around all over the place in a 10 kt crosswind running in Flight Gear, but hardly at all in a 16 kt cross wind running in the FSX environment.

 

There's even a mod included in FSUIPC to increase the side friction so you can taxi in even higher crosswinds. All in the name of realism. Skip to the last few pages.

 

http://forum.avsim.net/topic/392772-inherent-flaw-of-fsx-to-give-too-much-ground-friction/

 

I suspect FSX has done some simplification on the flight models and ground handling, even on higher realism settings. If you want a better GA experience, and don't mind a slower plane, try the J3 Cub from A2ASimulations, and get the Accusim mod. They're working on a 172 but no idea when it will be released. There are other good aircraft out there, but that's one I'm familiar with.

 

Hook

These things vary greatly between different aircraft models in FSX. Some planes are much more realistic than others.

I read the thread that Hook directed me to, and it is enticing but is lacking in specific direction on how to modify the ground friction. Also, which aircraft are more realistic in this regard?

 

RDS

I read the thread that Hook directed me to, and it is enticing but is lacking in specific direction on how to modify the ground friction.

 

Note: I'm quite happy with my ground friction and have no intention of modifying it. The only problem I've ever had was on takeoff roll where the aircraft might need to have the nose pointed a bit to the right to prevent left drift on the runway. I fly mostly taildraggers.

 

The fact that you think ground handling is too easy with default FSX means you probably wouldn't be all that happy with the mod.

 

Hook

The C172 behavior described by the OP is actually quite realistic. Real Cessnas don't get pushed around much, if at all, taxiing in a 16 knot crosswind. Landing hard does usually result in a "squat" and not a bounce (don't ask how I know!). Landing fast can get you a bounce.

 

To answer the question, it does seem that FSX is a better platform

There's even a mod included in FSUIPC to increase the side friction so you can taxi in even higher crosswinds. All in the name of realism

 

I disagree, it is thanks to the modifications made by Johan Dees and the implantation of it into FSUIPC (Perter Dowson) that an important flaw in FSX (the non realistic side slipping/skidding at correct landingspeed at dry runways) is now corrected.

 

About this thread:

 

http://forum.avsim.n...n/page__st__200

 

Hi everyone;

I've been steered over here by folks who are extremely interested in what's being discussed. As an adviser on realism for MSFS going back to the FSX Beta process I can tell you that this exact issue has been a thorn in my realistic side since the beginning. Over time I've discussed the issue with friends who were members of the Aces team and they are aware of my concerns AND the issue.

Reading over this thread it is apparent that the issue is well understood by the people discussing it and having Pete Dawson involved in this is a HUGE plus for the community.

I feel strongly you people might be well into finally solving this problem. I feel the issue is so important it represents perhaps the most important unsolved realism factor in FSX.

Considering I'm NOT a computer guy but rather on the aircraft/aerodynamics end of this equation I've noticed the issue being discussed mainly on takeoffs in MSFS. To expand a bit I've noticed it most on tail wheel aircraft after the tail wheel leaves a runway and the aircraft is on the takeoff run balanced on its 2 main gear. It's also noticable on nose wheel equipped airplanes but in my opinion not as pronounced.

I've described the problem to Microsoft as I saw it at the time during the beta as the aircraft seemingly rotating on a pivot axis in slew as opposed to what I felt I should have been seeing on a takeoff run with rudder input. I was seeing slew from side to side with the nose changing direction with a 0 change in ACTUAL direction. In the real aircraft I SHOULD have been seeing with rudder input a SERPENTINE WEAVE as the aircraft reacted to the applied rudder with the airplane changing DIRECTION. What I was getting was a slewing yaw on a PIVOT.

As some have said, exactly like the aircraft was on ice and hydroplaning in yaw.

Please accept my best wishes to all of you working on this. If the solution is found you will have succeeded in making desktop simulation just that much more realistic and more useful as a tool in real world aviation.

Dudley Henriques

MVP Microsoft FS 2006-2007

I disagree,

 

I'm not sure what you're disagreeing with in the post you quoted. There is a mod, it increases sliding friction, and it was done with the intent to make FSX more realistic. Does it not help with crosswind taxiing? Does it make it more difficult?

 

I read Dudley's post when it was still new.

 

As I don't experience the problems people seem to have, and I can't get anyone to do any kind of standardized testing so I can at least try to duplicate the problem, and most telling, no one wants to talk about their taxi speeds, then I see no reason to make any changes to my game.

 

I'm not the only person who had doubts about this mod, but only a very few even commented.

 

I think the mod is a great addition to FSX, but not necessarily for the stated purposes.

 

I have no problems on landing in the aircraft I fly, but touch down speeds are well under 100 knots, usually around 70. The biggest thing I've flown lately is a DC-3. I've seen some left slipping in prop taildraggers on takeoff. If someone is having problems in much larger aircraft during touch down at twice that speed, then maybe the problem is in FSX, maybe it's in pilot technique. I won't speculate at this time.

 

Hook

I'm not the only person who had doubts about this mod, but only a very few even commented.

 

This is probably wandering off-topic, but I certainly had doubts (and still have concerns) about it as well, as I do any mod which changes something which may have already been compensated for in some (or all) of my payware aircraft. Still, I was intrigued as I find taxi behavior in my payware GA planes to be one of the least realistic elements of the sim.

 

Larry, I wonder if the reason you don't notice this is because you say you fly mostly taildraggers. In steerable nose-wheel GA airplanes, the problem is pretty obvious. Turn the wheel and the airplane just doesn't react commensurate with the amount the nosewheel has turned. The plane's first reaction seems to be to skid against the nosewheel. To compensate and make my planes turn the way I know they do IRL, I find myself using toe-brakes to steer about as much as I would if I were steering a plane with a castering nosewheel.

 

When I enable the mod (I use the LUA module which negates the forward friction reduction part past a certain airspeed), ground handling seems markedly improved and subjectively more like what I'm used to IRL, at least in the limited number of my planes tested so far. Note I do say subjectively, and I'm still testing, but so far nosewheel steering finally acts more like it should. I've only tried one x-wind landing in one plane, but it also seemed an improvement.

 

To the OP it does sounds as if the sim you're used to flying may be a bit exaggerated. IRL, taxiing a 172 in a moderate crosswind isn't terribly difficult and you certainly shouldn't be pushed all over the place. I will say that some FSX airplanes do seem a bit too forgiving of hard landings. But fly one of the better payware models with a good flight model before you judge completely. For GA, try out the RealAir Lancair Legacy for example, or if you like taildraggers, as someone else mentioned the A2A Cub with Accusim.

 

Scott

Turn the wheel and the airplane just doesn't react commensurate with the amount the nosewheel has turned.

 

That sounds more like an animation problem with the nose wheel. Does the aircraft turn appropriate to the rudder input?

 

I find myself using toe-brakes to steer about as much as I would if I were steering a plane with a castering nosewheel.

 

I've seldom needed to use the toe brakes for normal steering. Sometimes a turn is just too tight, but I'm usually going about 4 knots maximum ground speed in those conditions and have no problems.

 

Check the turn angle in the contacts section of the aircraft.cfg file to see if the angle is reasonable. I've been known to edit this value if I think it's off, often to give a larger turn radius. The Carenado C337 Skymaster had this set at 35, but the trig worked out that 44 gave the correct pivot point according to a diagram I saw. Setting it to 65 would allow a turn around one wheel. The Grumman Goose had 90, which caused problems, and I changed it to 80. If I need to pivot around one wheel, I use differential throttle. The DC-3 originally had 60, and I'm using 40. Don't want to pivot around one wheel in that bird, it will damage the tires. The default C172 is 22 degrees, which seems about right.

 

Hook

That sounds more like an animation problem with the nose wheel. Does the aircraft turn appropriate to the rudder input?

 

The nosewheel view comment was simply intended to backup what I'm feeling. Nosewheel steering on most of my planes feels slightly behind and damped. Looking at things from the outside simply verifies what I'm feeling. As others have noted, it's rather like taxiing on slightly icy surfaces. Following the mod, handling seems to tighten up and control inputs (power and nosewheel steering) more closely match what I expect. Small pedal movements correlate better and more immediately to small adjustments in track.

 

I've seldom needed to use the toe brakes for normal steering. Sometimes a turn is just too tight, but I'm usually going about 4 knots maximum ground speed in those conditions and have no problems.

 

Sure, the slower you go, the less you'll notice the problem, but the slower you go, well... the more you'll run into the other problem. I don't have to use toe-brakes either, but I find I do more than I would IRL to compensate for the lack of immediate response and in order to get my planes to respond the way I think they should. Again, to me ground handling has always felt like one of the weakest points of the simulation. I can and do work around it to taxi smoothly but it has never felt very true to actual experience. So far, this change seems to address this weakness in a positive way - at least for the GA aircraft I've tried.

 

Check the turn angle in the contacts section of the aircraft.cfg file to see if the angle is reasonable.

 

I'm probably not articulating this as well as I should, but the issue is mostly about responsiveness rather than turn radius - but I do appreciate the suggestion.

 

Scott

I'll have to check this "fix" out.

 

I agree ground handling doesn't seem realistic in FSX. To make matters more confusing, different addons handle the handling (haha) differently. Even if both are equipped with toe brakes (I'm using Saitek Combat pedals) and are of similar type, the responsiveness is different between them. Also, OT: I wish my pedals toe brakes were much much harder to depress.

 

A few years ago I taxied and tookoff in a SR22 Gen1. It had castoring nose wheel. What a PITA to taxi (of course I'm used to Warriors where the pedals connect to the nose wheel). It was vastly different from the Warrior and especially noticable on takeoff (sort of a side to side motion). Granted I'd never flown one of those before. sorry random story lol.

 

Oh P.S - if anyone want's to link directly to the post in a thread you can hover your mouse over the post number (#216 or whatever) and right click, "copy link address" and it will put the link to that exact post in your memory, then paste... I think this is the part about FSUIPC entry:

http://forum.avsim.net/topic/392772-inherent-flaw-of-fsx-to-give-too-much-ground-friction/page__st__200#entry2541796