The answer is not that easy to answer. At the present we are doing extensive research in this special case. As a matter of fact early Fokker aircraft up to some stage of triplane production have painted their fuselages in a greyish-green or olive green color. We have a copy of the original type evaluation documents in our archive (downloadable for members from our website) and there is made a special mention of this point. The aircraft used for those testings must have had a painted fuselage, since the report done by Idflieg requested for future production that all steel tubing construction has to be executed according to the regulations of the "Bau- und Liefervorschriften für Heeresflugzeuge"(construction and delivery regulations for aircraft) with all welded parts being painted in clear paint to allow inspection of the joints. So the question should not be whether they have been painted or not, but rather more how it was done. We do not know for sure whether Fokker changed the method of painting the fuselage structure according to the request or not. We have some good photographs of later Fokker D.VII and D.VIII aircraft that have the frames painted in a non clear paint, but we also have some photographs of surviving parts of Richthofen`s 425/17, including one of the footrest mounted to the lower left fuselage longeron. This footrest is still mounted to a small cut off piece of the longeron and while the footrest itself is painted in black (as have been all removable parts), the longeron itself apears to be painted with clear dope as was requested. We have one of our members living in Australia who is going to check this in detail.
As a conclusion I would say the following: All steel tubing components have been painted in a coloured paint until it was requested by Idflieg to change this to clear paint during the triplane´s type evaluation process. Most possibly this was done during the following serial production of the triplane. Later aircraft again had their frames painted in colour. All parts that could be removed from the structure (for instance the footrest, the control coloumn, clamped parts and so forth) have been painted in black.
I hope this might be not totally confusing, but history sheldom goes straight ways.
In case you might be interested just pay us a visit at
http://www.collectors-edition.com/f-t-s_ti...h.htm
Your´s faithfully
Achim Sven Engels
Fokker-Team-Schorndorf