Hi,
I have been looking for KADET LT-40 (or similar) model for the FMS but couldn't find any.

Which model would have a similar behavior as the KADET LT-40 on FMS?

Thanks,
OG.

C'mon folks, someone must know the answer(?). There are probably more than just the two of us that would like to know what fms airplane behaves like an LT-40. Do you know the answer? Thanks.

Sorry guys, I don’t remember any of the FMS models being that close to the SIG LT-40. I used to fly FMS a lot. I built the PIC interface, the whole nine yards. I have tried quite a few of the FMS models. Don’t get me wrong, I like FMS. I think it is great practice regardless of how close the model is. Most of the “high wing trainer” types of planes in FMS have too much dihedral effect. That is, the simulated planes return to level flight much too quickly. Even though the LT-40 has a lot of dihedral, the self correction is less pronounced. Also, I never really liked the way the planes landed in FMS. These are really just nit picks since FMS is an absolutely amazing program - even more amazing that it is free.

I have a SIG LT-40 with and O.S. 46FX and I fly it all the time. I ended up getting RealFlight G2, so I put more effort into getting an LT-40 model for G2. Both FMS and G2 helped me a lot in getting soloed.

I currently use an LT-40 model for G2 and it is extremely close to the actual plane. For those interested see the Unofficial G2 Swap Page (http://zeus.rcwizard.com/fubar_hill/G2.htm). Over the last few months I have found that the frontal area needs to be reduced a bit in the G2 model. I’m new to the hobby, but I do have about 70 flights on my LT-40 so I am pretty familiar with the way the LT-40 flys. For everything aside from ground handling, the G2 model is effectively identical to the real plane.

For an LT-40 model in FMS, I think you will need modify an existing FMS model. Take a look at the RC-Sim.de site (in German but you can get to the download area easy enough):

http://www.rc-sim.de/index1.htm

See the download section under “Flugzeuge” - 16 download pages. This site has hundreds of FMS planes you can download. Download a few of the high wing trainer types of planes.

There is also a program call Par Designer that helps in editing FMS “.par” files so that you can modify the characteristics of FMS models. See:

http://www.interq.or.jp/sun/cyber/fm...s_GeoEX_e.html

You can add ailerons to models that only have rudder control, increase control throws, add power, adjust dihedral effect and the like. This will help you set-up the model to fly more to like the LT-40.

My LT-40 has a pretty slow roll rate, one revolution in about 1.5 seconds. So … I would just reduce the dihedral affect, adjust the roll rate and you’re in business. If I get a chance, I will hook up the buddy box, fire up FMS and see if I can give you more specific suggestions.

See also this link to some FMS planes (most of these models overlap with the planes on the RC-Sim.de site):

http://www.interq.or.jp/sun/cyber/fms_aircraft_e.html

Good luck,
Moses

Thank you for the elaborated reply.
So far, I found one model that is quite close (I think) to the LT-40.
This model can be found here:
http://www.hoops.ne.jp/%7Ekimagure-h...ger_index.html
Its name is: GPTRH

garye,
What do you think?

OG.

I checked out the GPTRH model. I think it is pretty good. The dihedral effect is close enough as it is. I set the Maximum Aileron Angle = .008 rad. I believe it was set to .003.

This is relatively close to the way my LT-40 flies now. When I originally flew the plane, the instructor told me the roll rate on my LT-40 with the stock set up was too slow (dangerously slow). We added some additional throw on several occasions. If you go with the base settings in the LT-40 manual, you may well have a roll rate that is slower (you will need to be adding some throw).

Be careful with the PAR Designer program. Mine is acting funny. Each time I run the program I must open the file (i.e., follow the path to the c:\program files\fms\model directory and select the “gptrh.par” file). If I exit PAR Designer (to try the model in FMS) and then re-run PAR Designer it looks like I’m still in “gptrh.par” (the title bar says “gptrh.par”). However, the parameters are all wrong. Just make sure you explicitly open the file each time you run the program.

Good luck,
Moses

OldGuru,

Seems to me that you are asking the wrong person for an opinion here...Not only am I a beginner, I'm nearly computer illiterate.

I did mangage to download the gptrh to both the hard drive and to a floppy, but when I try to open either one, the computer tries to open a PDF file, then tells me that an error occurred because the address doesn't start with "%PDF".

After that , it looks like there is a "zip" in the address, and I have no way(that I know of) to deal with that.

I would really like to open this thing - the LT-40 is my plane of choice, and doing some very basic training with it on fms sounds wonderful. If anyone knows of an easy way for me to get this thing to work with the fms that I did successfully download, I would greatly appreciate it. Thanks.

Garye, at least you downloaded the file. You need only do two more things:

1) unzip the files - gptrh.zip is a “zip” file – a compressed file (typically called an archive file) that contains several files (seven in this case) in one nice tidy little file.

2) put the files in the proper folder on your hard drive – in this case c:\program files\fms\model – this folder is where the FMS program expects to find the model files.

These steps are not difficult. You can unzip the files using a program such as winzip or winrar. You can unzip the files into a temporary directory and move them to the model folder or you can actually unzip them directly into the proper folder – winzip and winrar are pretty self explanatory. You can download an evaluation copy of these programs from cnet.com.

Each FMS model is made up of several files:

a .wav file for the engine noise
a .x file -
a preview file (so you can see a preview image when selecting the plane from the menu)
a .par file

The PAR Designer program helps you edit the .par file so you can tweak the model parameters. That’s about it.

Good luck,
Moses

Moses,

Thank You Very Much for the laymans 'how-to'. I was able to get it all downloaded and running - even the winzip. It may not be in exactly the right place, but at my level, who cares.

Now a question: The gptrh looks to be reasonably realistic in the air, but the final approach & touchdown have me wondering. I have heard that the LT-40 is a real floater on final but the gptrh seems to just mush right down, and touchdown seems to be extremely forgiving. OK, so I'm a beginner, and forgiving is good.

The SuperCup.par that was in the FMS 'package' when I downloaded it looks very realistic to my untrained eye, and seems to float forever and be a little less forgiving at touchdown. Yeah, I know, it's a taildragger and doesn't sound like an LT-40.

Considering that landing is one of the biggest challanges for a beginner, would practicing landings with the SuperCup be better than practicing with the gptrh? Thanks again.

Garye, I think the SuperCup may be a bit better than the gptrh for landing practice. Both planes fly ok. I think the SuperCup glides more like the LT-40 (perhaps a bit more than the LT-40). I adjusted the ailerons on the SuperCup to .004 rad. I also adjusted the dihedral effect to .004. This gives a more reasonable roll rate and reduces the dihedral effect.

FMS does not deal with ground friction very well. If the engine is running, the plane is moving. This does not happen on a grass field. The net effect is that I tend to set up FMS so that the engine is off when the throttle is pulled back. FMS simply makes engine noise in relation to air speed when you throttle back and come in for a landing (but the engine is really off). I guess most landings in FMS tend to be something pretty close to a dead stick. You can keep a click or two of throttle and adjust the glide slope of the plane accordingly (until the plane touches down). This will make planes like gptrh glide a bit better on landings.

I find the flight characteristics of the planes in FMS to be a bit different than the actual planes. I can’t tell you how to improve things other than the minor tweaks discussed above. Also, wind plays a major role in landings. Unless you are flying in dead calm, when the plane comes in, it gets pushed around a bit. It takes a bit of effort to keep the wings parallel to the ground. FMS does not simulate wind. The handling of the plane on the ground (e.g., on a grass field) is also not simulated. Sometimes you hit a bump and the plane bounces around. Even with all these issues, it’s still good practice.

Have fun,
Moses

Moses,

Wow! This is wonderful! I sure do appreciate the help. It looks like the next thing for me to do is try to change the ailerons & dihedral. On the other hand, at my level it may not matter.

Dealing with the float is the most scary part of this learning curve, so far. I've watched newbies run out of runway at my local air-field as they tried to get their trainers down...float, float, float. Pratice, pratice, pratice.

Thanks again.