This week I got sucked into the insane CAD timesink that is Google Sketchup again... this time designing the follow-on version of my SpaceShipTwo ParkJet Depron foamie model.

This first version was always intended to be strictly a demonstrator to see if the design of the real SS2- a very low-aspect ratio delta wing with outboard elevon control surfaces- flew well enough for further development.

Well, I'm happy to say that the SS2 ParkJet flies very nicely indeed.

So... here is an animation in Sketchup showcasing one of the "improvements" of the SS2.1 model- actuating feather system.

SpaceShipTwo RC Model vSS2.1 Feather Sequence (0 min 45 sec)

The Sketchup rendering above is not perfect - unfortunately due to my dubious skill level there are many things in that would take me hours to figure out in Sketchup but would take five minutes with an Exacto knife and microsaw on the real Depron thing. However, it is helpful tool, and a great way to figure clearances and etc.

The idea will be to gain as much altitude as possible, pull the power and slow to a stall, actuate the feather into re-entry config, then fold it back with enough altitude for recovery. It'll be interesting how she flies- er... falls- in this mode.

Besides the feathering system, the other major difference between SS2.1 and original model is use of a 70mm electric ducted fan (EDF) instead of the prop-in-slot pusher configuration on the ParkJet. The two models share finbooms and wing, with small modifications for type.

I'll keep posting stuff here as it moves along.