Thanks again for the comments guys. The design is way too close the the American Airborne logo to be used, so I have started sketching another version. The only thing I can think of is that I've seen it somewhere and it stuck in my head. Be it intentional or not, intellectual property rights are there for a reason and I will respect them.

Moving on.... I have at last finished rendering the 2nd dynamics test:

https://www.kickarz.com/AA_logo_spin02.wmv (save target as - 1.4Mb)

Note: this is just a test and will not be used as the main logo design will be changed.

Dave.