1) Launch Prepar3D
2 ) Choose as aircraft "Maule M7
3 ) Select Sion as airport (click on Airport and search for LSGS)
4 ) Confirm with "OK" and the flight will be loaded.

Check if you are on runway 07.
If you are on runway 25, taxi to the other end of the runway and turn around.

Prepare flight further:
4 ) Press "P" to switch the flight to pause mode.
5 ) Select in the menu Vehicle/Failures

6 ) Set in Failure Category "Engines" and search for "Oil Leak".
7 ) Set a check mark in the category "ARMED
8 ) At FAILS IN
enter 4 in the left field and 5 in the right field.
(This means 4-5 minutes after you exit the pause mode, an oil leak will occur).

9 ) Confirm the settings with "Apply".

10 ) In the menu select Options/General

11 ) Click on "Realism" and activate "Detect crashes and damage" in the upper right corner.
(If "Ignore crashes and damage" is activated, the flight makes no sense).
12 ) Confirm with "OK".

13 ) Select in the menu Scenario/Save

Save the flight:
14 ) Enter at File Name:
ExampleFlightNormal

15 ) Enter at Desctiption:
Example Flight where an oil leak occurs. This is a normal flight, not a mission. (Beispiel Flug, bei dem ein Öl Leck auftritt. Dies ist ein normaler Flug, keine Mission.)

16 ) Put a check mark at "Default".
(This will make this flight the "default flight", so it will be loaded automatically at the next P3d start. If you don't want this, leave it unchecked. By the way, whenever you load a flight, you can make another flight the "default flight").

17 ) Confirm with "OK".

Where to find the saved flight:

In your save directory (by default "C:\Users\YOUR NAME\Documents\Prepar3Dv6 Files") you will find 2 files:

ExampleFlightNormal.fxml (This is the flight.)
ExampleFlightNormal.wx (This is the weather settings.)

If you delete these two files, the P3d default flight becomes the "default flight" again.

Test the flight:

Now you can start flying. (Press "P" to exit the pause mode).
Take off, climb to 8000 feet at optimum climb speed 75-90 mph, follow the valley and enjoy the scenery.
You won't get far, because in 4-5 minutes the oil leak will occur.
As soon as the engine fails, set propeller to sail position and glide back to the airport at optimum glide speed (83mph).
Try to land at the airport if possible, if you can't, land gently off-road...

How to recognize the oil leak:
In the mouth you will notice the oil leak in two ways:
a) Oil leakage from the engine (you can clearly see it coming out of the engine).
b) The oil pressure decreases (you can see it on the instruments (Oil Pressure).

If you don't want to set everything yourself, you can also download this zip and copy the 2 files inside into your storage directory.

ExampleFlightNormal.zip