What spacing is needed between aircraft parking stands? I'm doing a project where I have to design an apron for a general aviation airport (ICAO type 2B). The airplanes have to park in angled nose-in parking, or angled nose-out parking. 

What is the required separation between two stands? I think that the dimensions of one stand depend on the turning radius of the airplane that is supposed to use the stand, but I don't know where to find this angle for every airplane... 

I'm looking for any data or other relevant information.
The Aerodrome Standards manual, which is based on ICAO Annex 14, gives the following values:

Clearance distances on aircraft stands
3.12.6 An aircraft stand shall provide the following minimum clearances between an aircraft using the stand and any adjacent building, aircraft on another stand and other objects:
Code Letter | Clearance
A | 3 m
B | 3 m
C | 4.5 m
D | 7.5 m
E | 7.5 m
F | 7.5 m

A references for the ICAO code letter categories is available here: http://www.skybrary.aero/index.php/ICAO_Aerodrome_Reference_Code