Cross-country Gliding Adventure at Zell am See (LOWZ) in FSX


In a recent post I discussed my first cross-country glider adventure using the Schleicher ASK 21 glider model in X-Plane 11.  That flight, which was published on my YouTube channel, was principally a ridge soaring task set at Zell am See in the Austrian Alps. This post details and links to another YouTube flight, which is a repeat of that task, but in the FSX Steam Edition simulator.

The YouTube video of this flight is best viewed in HD full screen mode if your Internet service supports it.

My intention in repeating the same task in these two flight simulators was to compare the virtual ridge soaring experiences that could be delivered by both products. To give some validity to this comparison between X-Plane 11 and FSX, I used: the same cross-country task course,  the same time and date, near identical weather conditions, and identical glider model types, although the glider models were made by different developers.  The only common glider model type available in both of my sims at the time of these comparison flights was the ASK 21 2-seater training glider. This meant using an add-on glider model in FSX. Leaving aside the motorized (self launching) versions, there were two add-on glider models of the ASK 21 available to me in FSX. For this flight I chose to use the Aerosoft ASK 21 rather than the ASK 21 available from Wolfgang Piper’s collection of freeware glider models because I am most familiar with that model from Aerosoft.

To be fair to X-Plane, I have no doubt that if I had compared both sims without any add-ons or plugins, then X-Plane would be streets ahead of FSX in any virtual gliding comparison. However, I am mostly interested in comparing the best possible virtual gliding experiences that these two flight simulators can provide me, including any available add-ons or plugins that I currently use to improve the overall experience.

Bear in mind also that I intend this to be a two part comparison.  These first two flights provide a comparison based on a cross-country task in an alpine location where ridge or slope lift is the predominant energy source for the glider.  In the second part of this comparison between X-Plane 11 and FSX, I intend to create a cross-country task in a flatland location where only thermal lift is available.

There is a discussion of the flight plan for this task in the YouTube video linked above.

Configuring the Soaring Environment in FSX

Obviously, time and date are the easiest components of the soaring environment to match up in the two simulators. Thus, in FSX, I set these to: 14 July 2016 at 14:00.

Matching FSX weather settings with those used in X-Plane turned out to be more problematic. Initially, I intended to use default FSX manual weather settings in conjunction with the CumulusX! add-on to re-create the soaring environment as near to that used in my X-Plane 11 flight as I could manage. However, I ran into a commonly occurring bug in FSX whereby multiple wind layer settings can be corrupted by the addition of turbulence and/or wind gusts in some layers. This led to failure of wind generation in FSX and thus no ridge lift in my first failed attempt. Moreover, turbulence and wind gusts in default FSX weather seem to be unrealistically abrupt and make the variometer very difficult to read because it does not have a gust filter.  To work around these issues, I opted to use the Active Sky 2016 add-on in custom manual weather mode to re-create the weather conditions. Even with the less abrupt wind variation generated by AS2016, the wild excursions of the Total Energy variometer needle on the ASK 21 proved to be difficult to read at times.  I seem to recall that the X-Plane ASK 21 had a similar issue with its variometer.

Following are some screenshots of my Active Sky 2016 weather settings.

NOTE: I started by selecting the default Realism Mode in AS2016. I then disabled any AS2016 wind updrafts or downdrafts so that CumulusX! could do its thing without unnecessary interference or augmentation to lift production.   I also set wake turbulence to zero because that effect seems too violent and the motion unrealistic for a glider following a tow plane.











This was principally a ridge soaring task, however, I felt that it was both reasonable and realistic to provide some thermal lift, which I hoped might assist with ridge transitions.

It is difficult match thermal conditions between X-Plane and FSX because FSX has the benefit of the CumulusX! add-on with comprehensive user control and documentation, whereas X-Plane provides minimal support for random thermal generation with only a percentage coverage slider and a thermal height slider for user control.  I chose to use the default settings for CumulusX!.  The default settings in CumulusX! provided a smaller thermal coverage than my chosen setting in X-Plane, but I wanted to  provide similar overall thermalling advantage to the task bearing in mind that CumulusX! provides cloud based thermals, which are easier to intercept, whereas X-Plane thermals are invisible “blue” thermals.

Following is a screenshot of my CumulusX! soaring environment settings.

NOTE: The Min and Max Lift Ceiling settings in CumulusX! do not apply for this task because CumulusX! gives preference to any cumulus cloud base setting in FSX. This was set by AS2016 to 10,153 feet.

Zell am See CumulusX! config


Results and Conclusions

Ridge lift conditions were remarkably similar between these two flight simulators for this task.  This was a surprise to me. I was expecting FSX with the CumulusX! add-on to provide a better ridge soaring experience.

The level of difficulty in completing the task was also much the same in both sims, although I achieved  a better average task time in X-Plane. I believe that the faster task time in X-Plane was probably more the result of my mistakes and tactical choices than to any differences in the way these simulators render the task. Also, due to my inexperience with X-Plane, I may have set the thermal conditions in X-Plane a little more advantageous than was needed in my effort to offset any anticipated disadvantage due it being limited to blue thermals only.

Both simulators had convincing flight models for me, although fluidity and dynamic movements seemed noticeably better in X-Plane using X-Camera and HeadShake plugins. I was using Chaseplane and A2A Accufeel add-ons with FSX, but I could not achieve the same level of immersion using the settings that tried for this task.

Sound effects seemed slightly better to me in FSX. X-Plane lacked any sound effects for the spoiler operation. The spoilers should make noticeable clunks when opening and closing and they should create extra drag and rumble noise effects. Modelling of aircraft vibration with the spoilers deployed was absent from both sims. The tyre squeal on a grass landing in X-Plane was awful and unrealistic.

The aerotow launch was definitely more realistic in FSX compared to X-Plane. In X-Plane the tow plane veered off the runway centreline as soon as the ground roll commenced, which I assume was a lack of control over the wind vane effect on the tug aircraft due to the cross-wind component in this task.  Also the X-Plane ground roll seemed far too short. Moreover, by default, X-Plane commences the launch automatically as soon as any glider flight loads. It would be much better if there was an option to have the launch manually started after instrument and control checks.

In regards to the alpine scenery around Zell am See, I believe that the X-Plane default scenery and mesh had the edge over FSX with Orbx global textures and Pilot’s Ultimate Mesh. This was mainly due to the apparent stretching of textures in FSX on steep mountain slopes. Also the scenery coloration in X-Plane seemed more convincing to me. River boundaries looked slightly less artificial in X-Plane, but roads seemed to be more unrealistically placed over the terrain mesh than in FSX, although both had problems. Each of the sims had a scenery anomaly. In X-Plane it appeared on the second leg of the task and it looked like a tile seam mismatch.  In FSX it appeared on the last leg of the task and it looked like a data issue in the terrain mesh.

The lighting and shadows are noticeably better in X-Plane. There was, however, some annoying flutter in cloud shadows evident in X-Plane. On the other hand, FSX does not even have cloud shadows.  CumulusX! has an option for cloud shadows for CumulusX! generated clouds but this option has issues, particularly in alpine areas, and I rarely, if ever, use it.

It would be unfair to compare airport scenery between the sims for this task because X-Plane was using default, but I inadvertently chose a location for this task  that included an add-on airport scenery from the Orbx European freeware airport packs.

In my opinion the issues mentioned and any that I may have overlooked are not major.  Overall, I am mightily impressed with both simulators and their ability to provide a convincing and entertaining virtual ridge soaring task with the Schleicher ASK 21 model glider. In the case of X-Plane, this is quite surprising to me given that X-Plane does not have a sophisticated soaring environment compared to FSX with the CumulusX! add-on.  It will be interesting to see whether both simulators will compare as equally when tested with a flatlands thermalling task. So that is my next intended YouTube project.

Connecting XCSoar to X-Plane 11 from a networked PC


I had a request in a comment on my previous post asking me to describe how I connect XCSoar to X-Plane from a networked PC. The following method is the one that I use, but there is at least one other way to do this using a freeware serial port emulation product called “HW VSP”. I have not tried the freeware option myself.   If you want to use the freeware “HW VSP” for virtual ports emulation then I suggest that you join the UK Virtual Gliding Association (also free) and ask for help on their forum. I believe that some of the UKVGA members use “HW VSP”.

I use the product called Virtual Serial Ports Emulator (VSPE) by You have to purchase a license to use it on 64 bit MS Windows.   I believe it is free on 32 bit MS Windows. Because I am running it on two 64 bit PCs, I bought two licenses but I am not sure if that is necessary or not. I have used it successfully on both a wired LAN and WIFI.  There may be a simpler way to do this, but this works and I have not bothered to try any other methods.

1. Install VSPE on X-Plane 11 PC and configure as follows:

Create a COM1 Connector device using default settings (this is the port that we will send X-Plane GPS output to). If COM1 is already in use on your system, you can use a different COM number.

Create a Splitter device with COM5 as the virtual serial port and COM1 as the Data source serial port. This will connect the X-Plane GPS output via COM1 to the TCP network server created in the next step.

Create a TcpServer device with Local TCP port 5555 and Source serial port is COM5. This virtual device will send the serial data stream received from the Splitter across the network to any TcpClients created with VSPE.

Save the configuration.  To re-load a saved configuration, you may have to stop the emulation first.

Click on the green start icon below the menu bar to start the emulation. Below is a screenshot of how it should look when you have started the emulation. NOTE: The emulation probably needs to be started before X-Plane  (it definitely does for FSX).

VSPE on X-Plane PC

I set this configuration up years ago, so I am not sure, but I believe that I used default settings for the VSPE emulation devices.  I provide screen captures of my settings in VSPE just in case I am wrong:

X-Plane PC COM1 properties:

X-Plane COM1 port properties

X-Plane PC Splitter properties:

X-Plane Splitter properties

X-Plane PC Splitter settings:

X-Plane Splitter settings

X-Plane PC TCP Server properties:

X-Plane tcp server properties

X-Plane PC TCP Server settings:

X-Plane tcp server settings


2. Install VSPE on networked PC with XCSoar installed and configure VSPE as follows:

Create a COM2 Connector device using default settings. This is the port that that XCSoar will read the GPS serial data stream sent from your X-Plane PC.

Created a Splitter device with COM5 as the virtual serial port and COM2 as the Data source serial port. This will get the serial data stream from the TCP Client device created in the next step and output it via COM2.

Create a TcpClient device with Remote TCP port 5555, The Remote TCP host  is the IP address of your X-Plane PC.  The Source serial port is COM5. This virtual device will receive the serial data stream across the network from the specified VSPE server PC.

Save the configuration.  To re-load a saved configuration, you may have to stop the emulation first.

Below is a screenshot of how it should look when configured.  Click on the green start icon below the menu bar to start the emulation.

With VSPE emulations running on both the server and client PCs and a successful network connection the status for each emulation device should change to “OK”.

NOTE: You may need to open port 5555 through your firewall on both the server and client PCs for the VSPEmulator.exe application.


XCSoar PC COM2 properties:

XCSoar COM2 properties

XCSoar PC Splitter properties:

XCSoar Splitter properties

XCSoar PC Splitter settings:

XCSoar Splitter settings

XCSoar TCP Client properties:

XCSoar tcp client properties

XCSoar TCP Client settings:

XCSoar tcp client settings


3. Start X-Plane 11 Go to Settings –> GPSHardware

Enable the moving map/NMEA COM port and set COM1 with 5 NMEA transmissions per second. You can experiment with the transmissions per second, but 5 per second seems to work OK for me.  (click on image to view larger size)

EDIT: I have carried out some testing of the transmission rate since this post and found that values less than 4 per second or greater than 5 per second impact frame rates and cause stutters.  So on my system, 4 to 5 per second works best.

X-Plane 11 GPS output setting


4. Start XCSoar on the networked PC.  Double click on map display to open menu buttons. Click on Config menu button, select Devices button and configure Device A to COM2 with Baud rate of 4800. The serial driver is optional, but I use the Condor Soaring Simulator driver, which seems to work OK.  There are an extensive range of drivers available in XCSoar. (click on image to view larger size)

XCSOAR Device config

My First Cross-country Gliding Adventure in X-Plane 11

I have been a strong critic of X-Plane, particularly when used as a virtual gliding simulator.  So when X-Plane 11 was recently released, I jumped right in with the default X-Plane glider, the Schleicher ASK21, fully expecting to be disappointed in the usual way. I decided to attempt  to complete a ridge soaring task, rather than using short ad hoc flights to test the soaring environment and flight modelling.  This cross-country flight test surprised me greatly. In spite of the obvious flaws in the X-Plane soaring environment, I was able to complete this task and, in fact,  I found the experience to be both entertaining and enjoyable.

Here is my full flight YouTube video:

When you compare X-Plane with default FSX as a virtual gliding simulator, neither provides a convincing virtual soaring environment. However, the availability of the CumulusX! competition soaring environment add-on for FSX makes a huge difference.  Moreover, there are a lot more 3rd party glider models available for FSX.  Until, X-Plane or a 3rd party developer can provide a competition (multi-player) soaring environment similar to, or better than, CumulusX!, FSX will remain as my preferred virtual gliding simulator. Nevertheless, I have been inspired by my first cross country adventure in X_Plane 11 to try some more test flights, and possibly some more full cross-country adventures, in X-Plane.

So let us now have a look at this specific cross-country adventure, which has changed my view, at least to some extent, about using X-Plane for any virtual soaring.   Firstly I will describe the task design and then the custom X-Plane weather settings. This will be followed by some discussion of issues that were noticed during the flight and my conclusions.


Task Design

I chose Zell am See in Austria as my launching site.  In X-Plane 11, the longest grass strip at Zell am See is 08L, so that seemed to be the best choice for my glider operations. However, I was later to learn that 08L no longer exists in the real world, which might explain why X-Plane has two roads running across the runway.

This is the flight plan created in Plan-G:

Flight Plan 2017-04-22_17-56-28 2


I put the start line on the ridge of hills running north from the airfield (TP SCM – Schmittenhoehe) and the finish line on the ridge of hills running towards the airfield from the east (TP HHN – Hahneck Kogel.)  The maximum start height was set at 6000 feet above mean sea level and the minimum safe finish height was set at 300 feet AGL above the finish line.

Local Sim Date and Time for this Task:

July 17, 14:02 local time


X-Plane Custom Weather Settings

Atmospheric Conditions and Thermals:

Capture 2


1st Wind Layer – at ground level (11 knots with mild turbulence and only slightly gusts from the SE):

Capture 3


2nd Wind layer – at mid ridge slope (strengthening with light turbulence and slight gusts, veering more southerly):

Capture 4


3rd Wind Layer – above the mountain tops (Stronger wind, smoother with no gusts and veering more southerly):

Capture 5


1st Cloud Layer:

Capture 6


2nd Cloud Layer:

Capture 7


X-Plane 11 Observations and Conclusions

Following are some issues that I noticed with X-Plane 11, but please note that I have very little experience with X-Plane in general and also bear in mind my previous comment that this cross-country glider flight was an enjoyable and entertaining flight regardless of these issues.  I may also draw some comparisons with Microsoft Flight Simulator X, although I do concede that these comparisons are somewhat unfair given that I have a number of add-ons in FSX that improve the virtual gliding experience greatly.

When I start a flight with the ASK 21 glider in X-Plane, it defaults to an aerotow and begins to launch immediately.  This is a bit of nuisance.  I haven’t worked out yet how to start a gliding flight with the wheel brake on, which might prevent an immediate launch. I would prefer to start the flight stationary and parked and then manually choose with keyboard or controller buttons whether to take an aero tow or a winch launch.

The aero tow ground roll seemed far too short to me, plus the tow plane got out of alignment with the runway as soon as it started moving – perhaps because it is susceptible to cross wind.

A nice feature in X-Plane is that tow plane can be manually steered left, right or straight ahead in flight, however, the turn rate is quite slow and does not appear to be adjustable.  This limitation may be a problem in some terrain situations. The CumulusX! smart tow option in FSX does not have this feature although it does allow you to pre-select either a left hand or right hand turn out after lift off.  I prefer the X-Plane feature.

There are two variometers in the X-Plane 11 ASK 21, which is not uncommon in gliders. It has an analogue vario and an electronic vario with a switch to enable the audio feedback.  The two vario needles appear to be in lockstep, so I assume they are both indicating the same thing. The analogue vario is calibrated in metres per second but the electronic vario only has tick marks.  The analogue vario looks very much like a standard “Winter” model Total Energy vario but it appears to react more like a Netto vario.  This is contrary to what is written in the X-Plane manual. The electronic vario audio feedback appears to have three distinct tones – a warble, a constant tone and a series of beeps.  The X-Plane manual says that the beeps indicate that glider is in an updraft and that the constant tone tells you that you are sinking but that does not correspond with my experience on this flight.  It appears to me that the frequency of beeps is a representation of the Total Energy input to the glider in the form of height gain and the constant tone pitch seems to be linked to the Netto vario  positive deflection representing the amount of lift in the surrounding airmass – in other words the constant tone appears to indicate that you are in an updraft and this is also contrary to what is stated in the X-Plane manual.  I haven’t worked out what the intermittent warble represents yet – it might be a glitch in the feedback sound. Even though the X-Plane variometer audio feedback is quite different to what I am most familiar with in some real-world gliders and in FSX, it is nevertheless quite useful once you get used to it and allows you to respond quickly to variations in lift while keeping your eyes outside the cockpit.

The ridge lift appears to be a tad erratic in X-Plane – certainly it is harder to predict than in FSX using the CumulusX! plugin.  The lift doesn’t appear to strengthen in indents in the ridge where the wind should get compressed and thus increase in speed and I haven’t noticed any decrease in lift at the base of ridges. Also I have not been able to detect the typical sweet spot of maximum lift slightly to windward of the ridge tops.  As I have no real-world experience with ridge soaring, I cannot say for sure that X-Plane ridge lift is not realistic – it just isn’t as convincing to me personally as it is with FSX + CumulusX!. Maybe I need to increase the wind speed a bit to get better and more consistent ridge  lift in X-Plane.   I have noticed that lee side effects such as excessive sink and wind rotor are either not modeled in X-Plane or at best are very weakly modeled.

The thermals in X-Plane are what we know as blue thermals – that is they are not associated with cumulus clouds. Nor are they associated with ground features as far as I can tell.  I recall hearing someone say that flying cross-country in blue thermals is a bit like a blind person stumbling across the countryside hoping to bump into to trees to climb.  Unfortunately, there is no 3rd party plugin that I know of to provide cloud based thermals in the same way CumulusX! does for FSX.

The in-flight sound effects  of the ASK 21 is reasonably convincing but it doesn’t include any variation for the airbrakes (spoilers) being deployed. Moreover, the spoiler deployment should be linked to the wheel brake on the ASK 21, which it isn’t in X-Plane.

The modelling of adverse yaw effect for the X-Plane ASK 21 seemed to be hardly detectable.   I don’t believe this is realistic for a glider.

The ground roll sound sound effects and landing tyre squeal are not realistic in my opinion.

I encountered two major pauses of the simulator during this flight but that could be my system or my X-Plane setup – further investigation required.

The lighting and scenery in this mountain area around Zell am See were very impressive in X-Plane 11, with the exception of the roads.  Also the default X-Plane 11 mesh looked rather crudely triangulated compared to what I am used to seeing in FSX with enhanced add-on mesh.

I encountered  one very obvious graphical anomaly in the scenery or mesh on the second leg of this task, and I got a good close-up look at this gap in the scenery in the video.

I managed to bump into a few thermals in this task and tried to stop and circle in one but it was too weak and difficult to center on the core.   Nevertheless, that thermal did appear to me to be quite realistic compared to some real-world thermals, which are often quite lumpy and bumpy and sometimes have multiple cores that are difficult to center on.

In spite of these issues, this was, overall,  a challenging and very enjoyable experience and I am encouraged to try some more X-Plane 11 glider flights in the future.  I may try a ‘flat-lands’ (thermalling) cross-country task next, even though I expect it to be very difficult without cloud based thermals.  Also I plan to repeat the Zell am See cross-country ridge soaring task in FSX as another YouTube video to see how different it will be using the CumulusX! add-on.