IO wing with LG 10.3 kilos !

New weight estimate that has all spars leading edge + 20 ribs and LG ( incl wheel + absorber ) with structure. 1 kilo has been counted for glue and paintjob ( + primer ). LG is about 1.6 kg. I mean IO will have100 % sure a flyable and sound system with that weight...I just don't know yet will it last 2-3-4-5-6 or more G:s. Ribs number has been increased they are now 20..of which 7 are so called heavy duty that take more load and give torsional stiffness and work as joining pieces for the plywood skin.


  1. "I just don't know yet will it last 2-3-4-5-6 or more G:s"

    Er, what load did you design it to? You know the standard in the field is to design to +3.8 g limit, +5.7 g ultimate, right? If you "don't know yet" whether you fill those requirements, what exactly does your structural design consist of?

  2. That is correct...it is to the sand bag testing whether it will hold or not the loads for a higher niveau...into aerobatics.

    This is stressed skin with spar only to the first wing joint ( about 6 ft ).

    The strong camper/curvature of the foil and thicknes palys a big role in making the structure light and durable.

    Carbon and plywood is used on the spar webs...also spruce to save weight ( instead of ply as filling ).

    1. Yes, you know the limit when you add enogh sand to break the wing...

  3. I don't understand. How can you sandbag test a part past the design limit loads? Are you building a bunch of them? Traditionally you have two options; (1) test to design limit, confirm that the deflection matches the predicted the deflection at that point, and keep the part; or (2) test to ultimate limit, either breaking the part or not, and discard it as permanently damaged. Once you go past design limit, you can't use the part in an actual aircraft. Without knowing what your design limit and deflection at design limit is, how is sandbag testing possible?