Thanks for the suggestions, I know Andy Johnston built a 27% 504 from David Boddingtons plans, I shall have a chat with him at Much Marcle this weekend if he is there and get his feedback.

I am looking to build either a 504 or 621 in approximately 1/3rd scale. Did Gordon Whitehead ever produce plans for his large 504 or were his plans kept when he passed away?

Failing that any suggestions of a plan already produced for either plane would be greatly appreciated.

I am putting together a component list for my 1:3.5 Tomahawk Wilga and currently looking at engine options. I fly from a noise sensitive site, adhering to the 82dB limit. My engine choices are 180-5 Moki / UMS 180-5 or 160-7 UMS. Has anyone got real world data on dB produced by any of these engines....