[Kari Lumppio]

Hello all!

I do have the Merrick opus, but didn't have noticed his explanation for the half-painted undersides (found in the photo caption on p. 103 and in text on p. 104).

But quoting the very same Merrick book:

(of the first 50 Fw 190 with unpainted undersides, page 102)
"... only the primer filler has to be applied on the bare sheet metal ... the deletion of camouflage paint has to be particularily noted."

(the first communication letter dated 4.7.44 - "Fw 190 abolition of camouflage paint on the aircraft underside", page 102):
"... For the priming of bare sheet metal we have considered the putty 119 D from the Warnecke & Böhm company, which we ordered on 16.7.44 by telex..."

(the second document on page 103):
"...Therefore it is not necessary to obtain special paints for this large-scale test other than the already quoted putty 119 D from the Warnecke & Böhm company"


I think we can all agree that filler/putty/primer 119 D was indeed used on the mentioned Fw 190 with unpainted undersides. Question is where and why?

If the deletion of camouflage was done because of saving raw material and time it makes no sense to putty the airframe only for cosmetic reasons. My guess is that the filler was used to make the airframes smoother and more aerodynamic.

On single-engined planes with tractor propeller the whole fuselage is in turbulent flow. Would puttying the fuselage seams bring any noticeable effect? I do not know for sure, but my guess is the effect would be neglible.

Making the wing leading edge smoother (especially on the 1/3 - 1/2 chord on upperside) would instead make a noticeable difference if the starting point was far from perfect.

This is my reasoning for suggesting the half-painted wing could be result of using putty surfacer.

Many authors also write about Fw 190 having upperside camouflage of consisting of some light grey primer (sometimes identified as RLM 77) and green/grey paint. Like mr. Hopp already wrote also Me 262 used primer. This type had podded engines (= fuselage in smooth airflow) and the fuselage seams were puttied and taped over to make it more aerodynamic (on NASM "Yellow 7" the primer on fuselage sides has been identified as Munsell 10 Y 7/1 - I don't have any FS for it). Was this finish on Me 262 waste of time and material? Why would it be that on making Fw 190 perform better?


For me this is all about getting an explanation which makes sense. I can't help myself thinking that the current explanations for the half-painted wing undersides (=special camouflage on wing undersides which are supposed to be uncamouflaged) are a bit exotic. I really hope that I am not getting anyone angry and apologize if this is the case.


With Respect,
Kari