On Friday, October 30, 2015 at 8:47:15 PM UTC-4, Jonathan St. Cloud wrote:
Please correct me if I am wrong, but doesn't the Butterfly S and the LX90XX with compass option both have fluxgate compass? One would think with these instruments we would not have to have a whiskey compass, that just takes panel/glare-shield space.

Perhaps LXNAV has the best chance of approval as the new LXNAV Compass module is advertised as a magnetic compass and sold as a separate (add-on) feature. A better job of "wordsmanship" than Air Avionics' Butterfly S.

If only the sailplane manufactures would release a Technical Bulletin stating these devices satisfy intention. But in today's world of government oversight and manufacture's liability risk, a snowball in hell has a better chance.