this is my second phase. Cutting out doors, laying out dimensions against a accurately scaled human test pilot, laying out general ground work for all the detailed mechanical parts (landing gear, door hinges, interior design, etc)
If this will be a vertical takeoff (also regular take off and landing) aircraft, the biggest challenge will be later on figuring out the mechanics that are believable in the real world. Half art but half taken seriously.
a) Do I design the main and rear engines to hydraulically rotate 90 degrees upwards during landing and take off? (like the Osprey military aircraft)? More moving parts
b) Or do I design air slots into the bottom of the aircraft and leave the engines as are? (like a harrier jet setup) less moving parts
c) Or do I design it kind of like the osprey where both front and rear engines (including the wings) rotate 90 degrees as one piece?