Here you can download free plans for a foam rc plane.
RC plane cardboard
canopy
El mejor PLANEADOR RC Sky Surfer X8
How to make a Aeroplane - Big RC Airplane
iFlight Turbobee 120RS Quad
The homemade wooden RC helicopter
SG907 MAX - Low Cost Drone with BIG Features (3 axis Camera Gimbal)
How to make CARDBOARD RC PLANE
Online calc of the CG of an RC airplane