Hi Regulus
I have Zeidler as a Fz.Mtr(Flugzeugmatrose) and that he was a member of MFJ II(marine Jasta) when interned on 3 April 1918...
However he could have been recently promoted.. :-/
He did join MFJ II on 31 March 1918 from Küsta III. It was during a test flight(alone) with an Halb CL II from MFJ I that he lost his way and landed in Holland.
The Halb CL II had the serial 14252/17 with a Mercedes 160 ps 35594.
He landed at Aardenburg, Zeeland. The a/c was later given Dutch serial H415.
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Gunnar