Now is single player you can own a Smuggler's Run Hanger, and store up to 12 aircraft

Missions: Moving Convoy
three armoured vehicles are moving from point to point destroy them for a reward
Smuggling Cargo
Just like the Supply runs from Executive Business

Required mods:
NativeUI(include)
Scripthookvdotnet (include)
Online Interiors(include)

to install drop folder and dll into scripts, make sure in OnlineInteriors.ini that enable hanger is false

what planes can go in what spots?
http://gta.wikia.com/wiki/Hangars
look at Storable Aircraft
(you can take any aircraft off the streets and put it into your hanger)