For few days already, I have finished the V-tail fuselage of the Needle 115 and flying with it. In fact it uses the short fuselage and the tails of the Neddle 124. Flying weight 2250gr, CoG 93mm like the cross tail fuselage.
For comparison, my second light crosstail N115 fuselage is 2200g, so 50gr less. But the weight distribution is not the same and is in favor of the V-tail version.
Maiden occured at the local slope with light conditions, so it was hardly difficult to see any difference.
However last week-end, we had a super good flying session at Puy de Manse with 13 to 16 m/s of wind.
It was the opportunity to test the V-tail version against the crosstail version.
About the same empty flying weight, 2250gr for the V-tail, 2200gr for the crosstail, 1.4kg of ballast, same CG, same wing settings (flap, reflex, snapflaps). It was just a matter of swapping the wings from one fuselage to another. Therefore I flew alternatively the V-Tail and the crosstail version of the Needle 115 all the afternoon.
First observation is that the crosstail is much stable than the V-tail that is having some light snaking sometimes. This is a well know caracteristics of the V-tail in general, lacking some lateral stability. Longitudinal stability is however great. I found the V-tail easier in Energy management turns with a good tracking, lots of "power" in the turn. In normal turn, the crosstail is more well mannered. I didn't notice any difference in term of straight speed, both are very fast.
At the end this is a question of taste, in term of look, and manners. Some pilots will prefer the crosstail for its polyvalence, others will adopt the V-tail for its agility thanks to the weight distribution. But this is good to have both available for the same wings. I came back from this afternoon with the following video: