What's New

Testing of the AirMule prototype is continuing.  As of June 2013 we have already accumulated a few hours of testing with the new six bladed rotors installed. The blade design complies with the loads specified in the FAA's FAR 35 standard for propellers.  To verify the strength of the blades we have built a representative blade retainment section and tested it as shown in the attached photographs. The tests were run to twice the centrifugal load (which amounted to 22 tons pull on each blade retention fitting).

Most of the testing at this time is focused on improving the automatic takeoff and landing sequence in preparation for transitional flight which will commence in the next few weeks.  The first transitional tests will be carried out with the aircraft still tethered to the ground but this time with a single safety wire long enough to permit flight to the end of the runway.  The full test sequence will be a flight to the end of the runway, stopping, turning 180 degrees in hover and flying back to the point of origin with a final landing on a marker placed on the ground.  We will update on the progress of these tests in our next update.
 

The testing of AirMule is continuing.  Initial hovers with Controp's D-STAMP payload (see April 2012 update) have shown a stable and noise free image of a landing marker placed on the tarmac.  The next steps involve estimating the position of the marker relative to the aircraft and having the FCS plan and execute an autonomous final approach for landing next to the marker.  We expect this phase to be completed in 2-3 months.

Another development is the completion of 'in-house' manufacture of 12 composite rotor blades (see picture below) for our two new six bladed rotors that we plan to install on the aircraft next month.  These rotors will replace the present, four bladed rotors that have been used since the beginning of 2010.  The new rotors have the same diameter and RPM as the original four bladed sets but are expected to increase the payload by approximately 200 Kilograms and are much closer to the final production version than the initial rotors were.  The design of the blade (section, planform, layup, wash-out, stress analysis etc.) as well as construction of tooling, rotor hubs, variable pitch mechanism, blades and all retention and other associated hardware have all been carried out by the engineers and workshop personnel at Urban Aeronautics.  The blade design complies with the loads specified the FAA's FAR 35 standard for propellers.