The pulley belt strut made
Th strut of the pulley belts has been made, see pictures of process. The pulley wheels now need to be cleaned out and the minor parts be fabricated. Barry will work on that. Asap that is done we can test the system with the team.
Option B elaborated
We elaborated option B now 12 motors with contra rotation on 6 hubs, so that you can have a look. The document is a PDF. If interested let us know, so we can share the spreadsheet behind it. Option B is almost similar in efficiency as the option with 6 rotors, basically due to the effect of loosing efficiency of the motors when drawing higher power out of it. With 12 motors the power draw is far less so less efficiency loss. The plan B tests will be needed at the same time as the 6 rotor system. We can then test the CW and CCW props of Xoar. See insert guide PDF. Interesting is that the tests can be done with different top and bottom motor speeds to see if there are optimum combinations.
Tube bending test
The results are above expected. The tubes alum. 60 61 T6 (aircraft spruce 1.5 inch with ca 1 mm thickness) were bent by a local company Van Harten metal working: www.vanhartenmetaal.nl with a bending radius of 1.6 m. The distorsion is less than 0.5 mm so quite good. Evertjan van Harten suggests that the tubes can even be bend to 1.2 m radius. So this gives us all flexibility to make a nice form and canopy looks. (whether this is already to be done with the first proto remains to be seen.)
Preparation airbagparachute tests
We did prepare some explosive and fabric to do a size test on the system. We ordered to reinforced sails of 5 by 5 m. and will make a simple 6 point star in from one and attach them. Add the explosive and see. The test is of course done on private property under save conditions
Connecting carbon fibre frame tubes is to be done with small connectors glued and secured with a glue. With the Lubribond (www.lubribond.nl) expert advice we now have the right glue to be tested once the connectors are ready. Great to work with them!
Developments in this area are exciting. The car industries is also showing more interest hydrogen fuelcell cars, and Toyota plans to have a model in 2015 2016 in the market. So fuelcells is still another option. We can therefore see that the current flight time of 10 to 12 min should be better! We have planned a visit to AMT Jets who's making RC aircraft turbines.