believed a medium-sized vehicle would be a more representative test of technology and would be directly useful to customers.
Cord said these characteristics cannot be met by conventional helicopters and fixed-wing vehicles. Conventional helicopters with the same payload characteristics can only attain speeds between 100 and 105 knots, while the SkyTote, equipped with hover capabilities, can attain speeds of 200 knots.
The change in payload capabilities created a more realistic, mechanical system, rather than a simplified concept demonstrator. It also created more challenges for developers.
"We had to choose a different type of engine, a 52-horsepower engine from UAV Engines, Ltd., a real engine that could be seen in a car almost," Cord said. "Our vehicle is 208 pounds, so we've grown significantly. We added a more complex transmission, too."
A more complex, heavier mechanical system also meant that developers had to look closely at the control aspects of the vehicle.
"The reason for this is that excess power reduces the need for a carefully conceived flight control system and helps avoid several problem areas, such as loss of control,” he noted.
“With less thrust-to-weight, we have to rely on the flight control system and the pilot to keep us out of dangerous flight conditions,” Cord described. “Autonomous control gives us an advantage during testing because it provides safer, more efficient tests."
During testing, SkyTote is expected to operate in hover and conventional wing-borne flight while also transitioning from hover to wing-borne and back.
A pilot will be standing by to take control of the plane, if needed. However, most of the testing will be controlled autonomously.
Developers say these transitions have to be done at least five times to demonstrate that SkyTote and its characteristics are a good concept and should be considered for future applications. The next cycle of SkyTote testing will be conducted in June at Camp Roberts in California.