New to XP11 - performance question

[vortex681 806]

1 minute ago, MarioDonick said:

Problem with aircraft at the moment is that many of them do not yet work correctly under X-Plane 11, because too many flight model changes have been made between 10 and 11.

Maybe I'll hang onto XP11 for a little longer and wait for a decent compatible helicopter.

[strider1 575]

42 minutes ago, vortex681 said:

Yes, just the Gazelle as I have many real-world hours in it. It's very good - certainly better than any other helicopter I've tried on a PC. The problem with helicopters is that there's just so much more going on aerodynamically than there is with a fixed wing aircraft and it's almost impossible to model it all. There simply isn't the processing power available in a desktop computer. I worked in the developement cell of a full-size, 6-degrees-of-freedom helipcopter sim for 3 years and even there we were finding things that didn't happen in the same way as with the real aircraft.

That sounds like a step in the right direction.

First a newbie question. Can you install add-on aircraft into the demo version of X-Plane 11? If that's possible, can you recommend a freeware helicopter which would give me a better idea of what X-Plane's capable of? As I'm leaning towards uninstalling the demo at the moment I can't really justify paying for add-ons.

Interesting. Could it be the Ryzen that's making the difference? How well does XP11 use the extra cores? Increasing the objects kills my frame rates but reflections to maximum hardly seems to affect me at all.

Thanks for that. That was exactly what I intended to say but, clearly, not nearly as well as you've put it!

Yes you could install ADD-ONS into the demo. But to be honest you should just suck it up and purchase the full copy ! 60 is cheap ! It will grow on you the more you use it ! 

I am not sure how well it uses the extra cores. Its suppose to be more single threaded then multi-threaded. I know it uses extra cores with AI. Make sure you have AI checked off, that could be killing your FPS.

Xplane really likes VRAM !

increasing autogen to max kills my frames. Will test and report back.

EDIT: I am looking at 30FPS on the runway, with autogen set to max at your resolution, and reflections set low, with 2xSSAA+FXAA! And 30 FPS on average in the air. 

I have 43" 4K monitor so I need to dial the Autogen back on high. Xplane on 4K is amazing !

I am hoping faster ram and bios updates will improve the FPS in the future ! And a new Vega + Vulcan ! 

 

[ryanbatc 12,857]

1 hour ago, vortex681 said:

I retired 5 years ago and rarely talk about my career, particularly on forums. The only reason I said that I'm an expert this time (see my post above for details) was that I knew that if I didn't I'd get flamed by all of the armchair helicopter sim pilots who think they know how helicopters fly. Short of sending you the last page of my fifth log book, there's no way to provide you with the undeniable proof you want.

Then I rest my case.

I don't think that I actually used the words "unacceptable performance" or "unrealistic flight dynamics". As far as the fixed wing aircraft go, I said that I didn't think the X-Plane was any better than A2A or RealAir - it's obviously subjective and you have the right to disagree. It was the default S-76 that I found disappointing.

The stock S76 is crap - sorry that was your way to evaluate XP11.  I'd recommend the Dreamfoil Bell 407 once they update it for XP11.

[Paraffin 2,197]

30 minutes ago, vortex681 said:

The problem with helicopters is that there's just so much more going on aerodynamically than there is with a fixed wing aircraft and it's almost impossible to model it all. There simply isn't the processing power available in a desktop computer. I worked in the developement cell of a full-size, 6-degrees-of-freedom helipcopter sim for 3 years and at the end of my time there we were still finding things that didn't happen in the same way as with the real aircraft because they were just too complex to simulate.

As I'm sure you're aware, one of the big problems in consumer-level PC helicopter sims is the flight controls. You get people trying to use things like twist joysticks for the anti-torque, etc. For the cyclic, a standard PC flight sim joystick is just too short and twitchy, compared to the more moderate input of a long-shaft helicopter cyclic. And they're spring-loaded for centering, which makes it hard to simulate things like force trim release. Inexpensive flight sim rudder pedals usually have a central detent that inhibits smooth pedal action. We can get full-scale sim controls that are closer to the real thing, but it's pricey.

Personally, I just use a Thrustmaster Warthog joystick and throttle, with the big spring removed from the stick so it's floppy, but with a small remaining centering action that works for fixed wing flying. It's a compromise for what I "should" be using for helicopter controls in a PC sim and I know it.

Regarding processing power -- note that X-Plane has a setting for "number of flight models per frame" which defaults at 2 fm's per frame. For light GA aircraft and helicopters I believe it's recommended to bump that up to at least 4 flight models per frame. This setting  doesn't seem to harm frame rate on most rigs.

Quote

First a newbie question. Can you install add-on aircraft into the demo version of X-Plane 11? If that's possible, can you recommend a freeware helicopter which would give me a better idea of what X-Plane's capable of? As I'm leaning towards uninstalling the demo at the moment I can't really justify paying for add-ons.

Except for certain payware that may require a specific location, most aircraft can just be copied into the /Aircraft folder under the main installation and they should run fine in the demo.

There is one freeware helicopter that's close to, or matching payware quality: the free Bell 429 Global Ranger, available here:

http://forums.x-plane.org/index.php?/files/file/34702-bell-429-global-ranger/

This uses (with permission) the plugin for the payware Bell 412, so you get the bells and whistles like force trim release, autopilot, SAS and ATT modes, beep trim, etc. Just download it and copy the folder under /Aircraft and you're set. You will have to use X-Plane's Settings menu to map your controller(s) for the added functions in the plugin.

NOTE: I'm not 100% sure this model has been updated to work in XP11 yet, so follow the developer forum to make sure there aren't any major issues that need addressing.

[jabloomf1230 2,445]

7 hours ago, rototom said:

Safe bet that a lot of those simmers have rotocraft ratings. But more importantly, none of these claims can be verified, so I'll go with majority. It aligns with most internet topics.

It's a safe bet that in real life most flight simmers  have never flown anything more challenging than a kite. Do you realize how few licensed pilots there are in the US? And then reduce that number even further by those with a rotorcraft skill set. I admire helicopter  pilots more than pretty much anyone else in civilian aviation. I'm not rated as such, but I have probably  500 hours as a passenger in UH1s. Even so, I feel unqualified  to critique the flight models of flight sim rotorcraft.

[PinkJackal 86]

Here are some datarefs for better performance, up to 15FPS more! The ones bolded are the heaviest on FPS!

--Draw Aurora Borealis. 0 (off) or 1 (on)
set( "sim/private/controls/reno/draw_aurora", 0.00)

--Draw aircraft carriers and frigates. 0 (off) or 1 (on)
set( "sim/private/controls/reno/draw_boats", 0.00)

--Draw birds and deer in nice weather. 0 (off) or 1 (on)
set( "sim/private/controls/reno/draw_deer_birds", 0.00)

--Draw fires and baloons. 0 (off) or 1 (on)
set( "sim/private/controls/reno/draw_fire_ball", 0.00)

--Road traffic density. 0 (off) to 5 (very dense)
set( "sim/private/controls/reno/draw_cars_05", 0.00)

--This setting was not used in XP10
set( "sim/private/controls/fbo/shadow_cam_size", 2048.00)

-- Draw fft water
set( "sim/private/controls/reno/draw_fft_water", 0.00)

[jcomm 5,938]

@Vortex...

The most realistic helicopter simulator experience I ever had was an ELITE FNPT for the EC-135. Regarding DCS, I did use that sim for a long while, mostly because of the UH-1H and the Mi-8 ( both offered to my great friend Zulfi :-) ). The Gazelle is the only helicopter resting in my user account @ ED's store, but I uninstalled it a few hours after trying a few maneuvers... and finding out I was capable of doing with it things I couldn't even think were possible in a RW Gazelle...

I did use a couple of excellent add-on helis for X-Plane 10, and also tried it in X-Plane 11, but between X-Plane 9 and 10, something happened to X-Plane's helicopters - they became over sensitive in roll cyclic, and you can easily axially roll them as if you were flying an Extra 300... This is, btw, a "feature" I found also in the DCS Gazelle...

But the older versions of rotary wing I tried in X-Plane 9 and X-Plane 10 initial releases, including those by Dreamfoil were really convincing to me.

 

No, I do not own a rotary wing pilot license, but I own a pilot license and keep flying for more than 36 yrs, and I am also a devoted simmer since more than 20 yrs...

 

I think X-Plane has a huge potential, provided it's main flight dynamics developer either dedicates a lot more time to it or hires someone to work on pair with him....

 

My sim is in my sig, btw :-)

 

 

 

 

 

[Murmur 3,941]

18 hours ago, vortex681 said:

In particular, I was itching to try a helicopter in X-Plane which everybody seems so impressed by but, frankly, I can only guess that people who think that way have never flown a real helicopter (trust me, I'm a real-world expert). The Dodo Sim 206 in FSX is much closer to real life (but still some way away).

There are a lot of rotary-wing related phenomena that X-Plane native flight model simulates, whereas MSFS native flight model does not. Some examples:

. translating tendency due to tail rotor sideforce (i.e. left skid low in a hover)

. retreating blade stall

. a much more complex modeling of autorotations

. vortex ring state

. translational lift

. the interrelation between rotor load and rotor RPM

etc.

Now, not all of these are perfectly simulated (every once in a while some of those get revised or retuned with the goal of improving them). And of course, as in any other flight simulator, having a realistic flight model relies heavily on the skills of the virtual aircraft designer, so you shouldn't expect every (or even most of) X-Plane helicopters to be 100% accurate.

However, remember that you're comparing a default X-Plane helicopter to the most advanced helicopter add-on available for MSFS (which, I suppose, is not 100% based on the default internal MSFS flight model).

Can you be more specific on what you don't like about the default S76? You haven't given any details, that might be of help.

 

[vortex681 806]

2 hours ago, Murmur said:

Can you be more specific on what you don't like about the default S76? You haven't given any details, that might be of help.

I set the aircraft up at 10,800lbs (heavy) with temperature 15degC and 1013HPa at Seattle.

Observations:

Lift to the hover - little to no pedal input required (it actually needed a tiny bit of right pedal which is completely wrong, even with a crosswind). Normally you'd need a significant amount of left pedal. The pedals are definitely working correctly as I can carry out a pedal turn in both directions.

A stable, low hover required about 35% torque. I would expect it to use at least twice as much torque as this at the high operating weight.

Climb at best ROC speed (75kts) with about 60% torque set - 2,100 feet/min rate of climb. That's not far off what you'd expect at 100% torque at that weight.

If you try to increase torque towards 100%, maintaining 75kts, both engines back off and the aicraft pitches up as it reaches about 70% torque (which seems to be about all you can get) without sufficient forward cyclic control to stop it. The aircraft is well inside its operating limits and the FADEC should easily maintain the rotor RPM and engines at 100% in these conditions. Where the pitch up comes from is a bit of a mystery.

Enter autorotation with both engines running - little to no pedal required to keep straight and if the cyclic is held steady there is a large pitch down. The rotor RPM sounds as if it's rising (correct) but there doesn't seem to be a rotor RPM needle on the guage to check this. A little collective required to hold, what sounds like, 100% rotor RPM (correct).

Shut down engines in a stable autorotation whilst fully lowering collective - sounds as though rotor RPM is reducing, which it should slightly (but no indication), and trying to flare (load up the rotor) does not help. Nose then pitches down uncontrollably.

 

You mentioned that X-Plane has much more complex modelling of autorotations but that doen't seem to be the case with the default S-76. I made sure that all of my controls were calibrated before I started and had the collective assigned to my throttle.

[Murmur 3,941]

28 minutes ago, vortex681 said:

I set the aircraft up at 10,800lbs (heavy) with temperature 15degC and 1013HPa at Seattle.

Observations:

Lift to the hover - little to no pedal input required (it actually needed a tiny bit of right pedal which is completely wrong, even with a crosswind). Normally you'd need a significant amount of left pedal. The pedals are definitely working correctly as I can carry out a pedal turn in both directions.

[CUT]

You mentioned that X-Plane has much more complex modelling of autorotations but that doen't seem to be the case with the default S-76. I made sure that all of my controls were calibrated before I started and had the collective assigned to my throttle.

Looks like the default S76 has been programmed with an over-enthusiastic stability augmentation system. Most other helicopters in X-Plane require a lot of rudder during hover.

Regarding the rest of your observations, apparently the S76 performance hasn't been tuned particularly well or accurately.

You should try to install some of the most popular helicopter downloads for X-Plane 10 available on www.x-plane.org file library. You can sort them by popularity, and the most downloaded tend to be the best ones (even if not all of them may have the best flight model, but some of them should be good and more accurately tuned than others).

I would be interested to read your observations after trying some more helicopters.

 

[rototom 198]

25 minutes ago, Murmur said:

Looks like the default S76 has been programmed with an over-enthusiastic stability augmentation system. Most other helicopters in X-Plane require a lot of rudder during hover.

Regarding the rest of your observations, apparently the S76 performance hasn't been tuned particularly well or accurately.

You should try to install some of the most popular helicopter downloads for X-Plane 10 available on www.x-plane.org file library. You can sort them by popularity, and the most downloaded tend to be the best ones (even if not all of them may have the best flight model, but some of them should be good and more accurately tuned than others).

I would be interested to read your observations after trying some more helicopters.

 

I haven't noticed yet, but does XP11 allow you to adjust the stability augmentation like you could in version 10? This was also supposed to help compensate for various types of hardware that are not ideal. I typically used around 12-15% on all axis.

I'll give the S76 a go and see how it compares to the other helos I have in version 10.

[alpha12125 213]

i am no expert in heli operation in x-plane or in real life, but the things you mentioned are pretty much symptomatic of the default planes. With the planes it is not really alot different. If you want any sort of accuracy you have to go to the dreamfoil helicopters. For a payware they are not even that expensive, especially when they are on sale.

[Murmur 3,941]

1 hour ago, rototom said:

I haven't noticed yet, but does XP11 allow you to adjust the stability augmentation like you could in version 10? This was also supposed to help compensate for various types of hardware that are not ideal. I typically used around 12-15% on all axis.

Yes, it's in the joystick menu, but it's a different thing from the fly-by-wire stability that the aircraft designer can equip the aircraft with using plane-maker.

2 hours ago, vortex681 said:

You mentioned that X-Plane has much more complex modelling of autorotations but that doen't seem to be the case with the default S-76. I made sure that all of my controls were calibrated before I started and had the collective assigned to my throttle.

This seems to be the best freeware helicopter available for X-Plane and is compatible with X-Plane 11.

http://forums.x-plane.org/index.php?/files/file/34702-bell-429-global-ranger/

Although I don't know if it's equipped with some sort of stability augmentation system as well.

Another thing to check, is that the "stability augmentation" for the joystick (available in the "Joystick"->"Control Sensitivity" menu) is zeroed on all three axes. This "joystick stability augmentation" is an additional "fake" stability augmentation attempting to compensate for the reduced travel of PC flight controls. It affects all aircrafts and can make their handling less realistic.

 

[Paraffin 2,197]

10 hours ago, jcomm said:

I did use a couple of excellent add-on helis for X-Plane 10, and also tried it in X-Plane 11, but between X-Plane 9 and 10, something happened to X-Plane's helicopters - they became over sensitive in roll cyclic, and you can easily axially roll them as if you were flying an Extra 300... This is, btw, a "feature" I found also in the DCS Gazelle...

I don't find the cyclic overly sensitive at all, but we probably have different controls or sensitivity settings.

Yes, I can roll the DreamFoil Bell 407 (just tried it to make sure in XP11 1.0), but the rate is predictable and not sudden or twitchy. It's almost exactly the roll rate shown here (Red Bull display):

https://www.youtube.com/watch?v=413EyCwUDCw

[jcomm 5,938]

Yeah, for me it's a lot faster.

BTW: That's an MBB, not an EC ...