Last year I received an enquirey about the details of this paint scheme:
It is a nice looking design that I have seen before, but having no information about it I referred the question to Rick Wenger, the current owner of A-15. Rick provided so much interesting information that I thought I would share it here.
Firstly, the above paint schemes are fake! Neither A-15 nor any other Swiss Jungmann ever wore such a scheme.
Rick suggested that there are other color schemes that were used, and which might be of interest. Before the well known yellow/black/red scheme was introduced, Jungmann in Swiss military service were painted white/cream and silver. This picture is from early 1939 and although a monochrome picture, you can clearly see the design in use. The red Swiss crosses are placed in the same location as in the later black/yellow scheme. The details are here. It is tempting to think that the white cross is composed of five white squares, but that is not the case. The legs of the cross are a very specific shape.
It is also interesting that you can see in this pictures that the aircraft were not always marked with "A-", in 1939 just the number was applied to the fuselage sides. The "A-" was added later, before the adoption of black/yellow colors.
The following two pictures give an idea of what the colors should look like:
It is quite well known that Swiss civil aircraft generally display a horizontal red band with a white cross like this: 
While in military service, the whole rudder is red with an embedded cross:
But there was also an intermediate form. For a while military aircraft that had been transferred to the civil register could be painted with the military style red rudder but with white lines above and below the white cross:
Thanks to Rick Wenger for providing the information and the pictures.