I don't know how many rubber bands you're planning on using, but in the pictures you only have a couple. Make sure you use at least 12-14 rubberbands to hold the wing on.

If you haven't already, you may want to glue some bamboo skewers into the leading and trailing edge of the wing wrap. This will keep the flutes from crushing, which they will do when you get that many rubber bands on.

Brad