• The Biplane Forum is a large global active community of biplane builders, owners and pilots. From Pitts to Skybolts, to older barnstormers, all types are welcome. In addition to our active community, our content boasts exhaustive technical information which is often sought after for projects and maintenance. This information has accumulated over the 12+ years the forum has been in existence.

    The Biplane Forum is a private community. Subscriptions are only $49.99/year or $6.99/month to gain access to this great community and unmatched source of information not found anywhere else on the web. We are also a great resource for non biplane users, since many GA aircraft are built the same way (fabric and tube construction). Annual membership also comes with two BiplaneForum.com decals.

Upper wing attach fitting


Well-Known Member
Sep 6, 2006
Reaction score
Morning Folks,

Bit confussed about the front and rear spar center section fittings. I take it there are 1/4" holes for the spar attach part, the upper part. Then there are 5/16th holes for the rear attach fittings only, lower part? and no 5/16th holes for the front attach fittings. Just need to measure twice before I drill once and have to make little parts from big now scrapped parts. Erich

Latest posts