Just got permission to share a project i'd worked on in April 2011.
All the work was done with Blender (minimal use of Photoshop and Illustrator for the decals).

Had been working with Blender for a few years, mainly playing around and uploading test renders.. like this one of a V.T.O.L (Vertical Take Off and Landing)

An aircraft designer from california saw it and contacted me. Oliver Garrow's been designing various V.T.O.L aircraft and needed help in visualizing one of his new designs in Blender. The aircraft is called Verticopter II and the project seemed interesting, so i took it on. The project was confidential at the time, which is why i had to wait till now(for him to go public with it) before i could post anything about it.

The Beginning
I started with these diagrams he sent me

the basic form had been blocked out and the functional elements had been clearly demarcated.. this followed by a Skype call, and i was ready to begin the modelling. The overall form was pretty much upto me.
So i began with building a sleek fuselage and detailed out the undercarriage

Refinements
The initial reaction was that the nose was too pointy. also i realised that since this was a relatively small(2seater) aircraft, the pilot would need a lot more leg room in front, so we decided to extend the nose forward and down
(after referring to a few pics of existing aircraft). Also added windows and details for the interiors

This was by far the most extensive project i've ever worked on in Blender, it gave me a new appreciation for the layout and flexibility of the new 2.5 interface.

Animation
This part was tricky, there were so many moving parts to keep track of, really loved working with the Animation Layout, just made everything easier to manage.

Rendering
The cycles engine had just been announced but the builds were not available yet, so i went with the standard renderer.

This is where it got crazy, Oliver needed the footage in HD, which was taking forever to render on my one machine. Thankfully he offered to run the render process on his machines at home and work, and thats how it all got done.

heres the finished animation that oliver put together.

heres are some follow up renders i did for him to use in print material

drop by the verticopter site to see the progress on the actual aircraft.

UPDATE:
a few weeks later Oliver decided to simplify the tail section, so this is the new design

removed the propeller covers as they were too cumbersome to control and presented manufacturing problems.