Junkers Ju 52/3m engine mounting angle

[GrahamB]

Over recent weeks and months I have been delving into the complex history and development of the Luftwaffe’s incredibly resilient and hard-working Junkers Ju 52. Reference books on this aircraft are amazingly inconsistent in the details of the structural changes and camouflage (see my other posting) although the recent Classic Colours Transporter has got very close. There is one major feature that I think is wrongly presented in almost all cases: a Heller 1/72 Ju 52 on my workbench seemingly has deformed outer engine cowlings, so that the rear profile is not a perfect circle, as one might assume. Also, the cowling shape is asymmetrical, not what one would expect if the engine was mounted parallel to the swept-back wing leading edge. The consistent impression and presentation in illustrations and plans (e.g. Squadron/Signal, AirDOC, Profile Publications, Model Fan, Flugzeug Profile, Classic Colours ‘Transporter’ volumes, and even the RLM camouflage diagram itself!) is that this was the case – the radial engines were mounted parallel to the leading edge, giving them an outward cant of about 6 degrees. I was suspicious about this because I was not convinced by looking at many photographs (all photographs from a front angle of multi-engined aircraft will show the wing cowlings apparently divergent). As cameras do not have perception one has to account for the camera angle when interpreting photographs and using other features as a control. In the case of the Ju 52, the undercarriage is a useful guide. As is usual, finding photographs that would definitely solve the problem was difficult. Fortunately there is one in Squadron/Signal ‘In Action’, page 29 lower left of a Ju 52 floatplane. The camera view appears to be directly in line with the starboard engine nacelle but the cowling is clearly not aligned symmetrically but is angled inwards. On page 41 of ‘Transporter vol.1’ taken from behind and above, the photo also shows the asymmetric alignment and Heller’s cowling shape to perfection, as does the colour print on page 78. Other photographs in the references mentioned show this less well.

I think this is pretty convincing proof that Ju 52 3/m aircraft with BMW 132 engines had them mounted perpendicular to the line of flight. In fact, this is actually stated in ‘In Action’ on page dealing with the Civil Variant Ju 52/3m ge! It is strange how this has eluded everyone else – although Don Greer’s fine paintings on the book’s covers seem correct.