Improving the Cessna 172

9 August 2020

Increased engine power to 210 HP ( same as the Reims Rocket and Cessna 172 XP), climb rates are improved but cruise speed is not much different, still a worthwhile improvement. I just edited the HP tag in the JBSIM model file to 210 hp

Final set of improvements to be done:

• Standard instrument layout as much as possible (standard T)

• Replace 3D pilot with a newer one

• Smooth out tail surfaces

• Add animations, flaps, prop, throttle, mixture, etc

• Add internal map holder with maps with changeable pages

• Add all other instruments needed - radio, autopilot etc.

Of course I could release a Beta model.

29 June 2020

It is much easier now using the Wings 3D modelling environment and using the .3ds format that Wings 3D can export and import directly, without any errors. Editing or modifying aircraft much easier and more pleasant.

Latest additions to the Cessna 172 are : a pilot, instruments and interior colors. Interior materials need to be sorted out as some of them are not showing as expected.

I also did some cross country flights from KSJC to JSCK (Stockton), found the airport, and landed easily, it was a very pleasant flight, using the autopilot from the menu. Referring only to the ASI, ALT, and VSI without the airtifical horizon, using the outside as a reference point was much easier and more accurate. After the Mirage 2000, landing was almost too easy, though the cross wind landing at KSCK was not quite what was desired.

Rename the folder: in my case have renamed it to c172pFG1234 and that shows in the FGRUN Flight Gear Launcher listing instead of c172p (copy1). So changing the aircraft folder name causes this name to change.

The next step is to modify the 3D model. Changing the paint scheme (called texture in 3D modelling terms ) on the aircraft, which will result in a change in the appearance of the airplane. To make the change show up in the launcher, we will have to edit the model file named c172p-set.xml which is inside the folder aircraft//c172pFG1234/

Change the path to the folder to refer to the new folder, this line is found inside the <model> tags:

<model>

<path archive="y">Aircraft/c172pFG1234/Models/c172p.xml</path>

</model>

Now the Cessna 172p with the new blue livery shows up in the launcher.

There is one more step needed to make the airplane load into Flight Gear. Displaying the launch parameters from the fgrun launcher shows the following :

C:\Program Files\FlightGear\bin\Win32\fgfs.exe

--fg-root=C:\Program Files\FlightGear\data

--fg-scenery=C:\Program Files\FlightGear\data\Scenery;C:\Program Files\FlightGear\scenery

--aircraft=c172p

Fgrun is launching the original c172p, obviously there has to be a way to launch the modified aircraft by changing a parameter somewhere.

Change the name of the -set file in the new airplane folder (...Aircraft/c172pFG1234/) to the following:

c172pfg1234-set.xml

This works. Fgrun displays a different --aircraft parameter when launching:

--aircraft=c172pfg1234

What has happened here? Flight gear uses the first part of the -set file to identify the aircraft. Selecting this name launches the aircraft model named c172pfg1234.

To summarize, when making a copy of an existing aircraft and making changes to that aircraft, these steps must be followed:

• Copy the aircraft folder

• Rename the aircraft folder (if you use the same name for the new folder, the aircraft will not be listed in fgrun)

• Make changes to the 3D file or texture of the aircraft

• Edit the -set file to refer to the model within the new aircraft folder

• Change the name of the -set file.

Some of the configuration files inside the c172pfg1234 folder will continue to refer to and use many files in the original folder, but this is not a problem right now. If we want to change anything we make changes in the local folder and change the references as needed.

June 26, 2020

Along with some knew found knowledge and confidence in knowing how FG works, continuing the improvement of the Cessna 172: The above steps were followed, in addition, the highlighted files were cut and pasted into a separate arhives folder as they were unnecessariy complicating my model and needed ot be undrstodd befire used.

Similarly for the model files:

Lets see if the model will load:

It does not show up in the launcher. Very well there is a model that was tested as loading earlier adn so that is copied to the folder, a 3d model and the model file is made to refer to that model,

I deleted a whole lot of stuff, reference to nasal files, panel, kp autopilot and everything until I was left with the following int eh set file:

Model not loading, loading old model:

C:\Program Files (x86)\FlightGear\bin\Win32\fgfs.exe

--fg-root=C:\Program Files (x86)\FlightGear\data

--fg-scenery=C:\Program Files (x86)\FlightGear\data\Scenery;C:\Program Files (x86)\FlightGear\scenery

--aircraft=c172p

--control=joystick

Again, this was fixed by changing the name of the -Set file although inside the folder new folder, it has o t be of a dfirrent name or the system will use the -set of the other aircraft previously on tp of this owne