Jaba,
My name is Robbie Asplund. I'm attempting to honor Josef Wirtz of MFJ-I for our project. But yes, Wirtz was a Marineflieger who died in combat in April 1917. He died as a Vizeflugmeister, but I'm as yet unsure what that rank translates to on the uniform. Flugmeister and Oberflugmeister I know, but how the "Vize-" is represented on the uniform is beyond me at the moment.
Cheers,
Robbie