Israeli manufacturer Urban Aeronautics is testing its AirMule vertical take-off and landing unmanned air system with new propellers to enhance its capabilities.

It has replaced the UAV's previous four-blade propellers with new six-blade composite versions.

The new rotors retain the diameter of the originals and operate at the same RPM, but are expected to increase the aircraft's payload by approximately 200kg (440lb).

In a parallel effort, Urban Aeronautics is accelerating the assembly of a second AirMule prototype in preparation for a series of demonstration flights requested by potential customers.

The second prototype is intended primarily as a reserve aircraft to ensure uninterrupted flight testing once customer demonstrations, planned for mid-2014, are underway.

Additionally, the company plans to complete an automatic precision landing demonstration in the next few months. A small stabilised electro-optical payload to enable the test has been installed on the AirMule prototype. Manufactured by Controp, the D-Stamp system will allow the aircraft to guide itself to touchdown over any high-contrast marker or laser spot placed.

This feature will be the final step towards enabling fully autonomous flights using pre-programmed routes. Accurate positioning will be maintained en route by an onboard inertial navigation system in conjunction with a GPS or, alternatively, a Doppler navigation unit.

Source: Flight International