RangerX3X released a singleplayer mission in the BI forums.

Quote RangerX3X :
You are a helicopter pilot on the deck of the USS Khe Sanh. You have three helicopters at your disposal: AH-1Z, AH-64D and a Mi24D (CDF with a CDF gunner). Each helicopter has an assigned gunner who will be automatically assigned to you when you enter the cockpit of your choice aircraft. Upon exiting a helicopter to choose another one, you will be assigned that helicopters gunner as your gunner and dis-assigned any other gunner you may have had previously grouped to you when entering a previous helicopter.