Why In The World Did Delta Air Lines Change The Winglets On Some Aircraft?

Atlanta-based legacy carrier Delta Air Lines (NYSE: DAL) retrofitted several Boeing 737-800 and Boeing 737-900ER aircraft with Boeing’s special Split Scimitar Winglets, and subsequently upgraded these models with Aviation Partners’ Blended Winglets. This unique winglet adds both a reshaped upper winglet and a downward-facing strake in addition to changes at the tip of the winglets, which were designed to weaken the wingtip vortex significantly.