Not the norm obviously but allowable none the less..........................
From the CDL…………….winglets, 2 fitted, one may be missing provided hole is covered. The following performance penalties are applicable:
Take off and approach climb performance limiting weights are reduced by 17 150kgs
One engine inoperative net ceiling reduced by 884ft
Fuel consumption increased by 1.20%
http://www.jetphotos.net/img/1/1/6/6...5487661_tb.jpg