What is the purpose of the winglets on the Socata TB-31 Omega vertical stabilizer? Aérospatiale-Socata built a prototype of the TB-31 for the French Air Force, which never went to production:


Source: netAirspace.com, photo by miamiair

What is the purpose of the winglets at the top of the vertical stabilizer?
What you observe here are VHF nav antennas for a VOR receiver.  This antenna design is lower drag than wire whip antennas.

The antenna serves no aerodynamic purpose except to minimize its own drag profile.