Howdy all;

While at Oshkosh (which was great), I did some talking to other Kitfox guys and had a realization. A while back, I proposed building a Kitfox Model 4-1200 with a gross weight of 1250 lbs. I justified this because the current load specification of an ultimate wing loading of 7200 LbS (1200 lbs x 6 G’s) would become an ultimate wing loading of 5.76 G’s at a gross weight of 1250 Lbs, which still placed the kitfox within the “NORMAL “ category for wing loading as outlined in FAR Part 23. For example, if this was a certified plane and the Kitfox was designed to comply with the FAA specification for NORMAL category, it would need to operate at 3.8g’s, and be built with a safety factor of 1.5 (as outlined in FAR 23.303), which corresponds to a ultimate positive G load of 5.7. As mentioned above, at a gross of 1250 Lbs, the model 4 would have an ultimate wing loading of 5.76 G’s. However, having said all that, a 1250 Lbs gross kitfox was kind of boarder line. But now I have a better idea:

I noticed that the model 4 speedster has a shorter wing, and that it is rated with an ultimate load limit of 9 G’s at an operating gross weight of 950 Lbs (for aerobatics). This corresponds to an ultimate wing loading of 8550 lbs. If I figure on using the shortened speed wing, the kitfox 4 at a 1250 lbs gross would now have a ultimate positive wing loading of 6.84 G’s, which places it well with within the NORMAL category with a safety factor of 1.8. In fact, with this level of safety factory, the kitfox 4 COULD be operated in the UTILITY category of 4.4 G’s, and still have a 150% safety factor.

Of course other changes to the airframe would be needed, most notably the landing gear.

What do you think, does this case hold water?

Roger