Entecho's Hoverpod: the 3-seat, skirt-steered, 75mph VTOL flying saucer
By Loz Blain
May 4, 2009
May 4, 2009 We continue to be optimistic about the future of personal flight - and from flying cars to coaxial flying platforms, ion-powered jetpacks and more recreational solutions, plenty of innovative designs are striving for viability. We haven't seen anything like this one before though - Australia's Entecho has come up with an operating prototype of a sort of cylindrical fan-forced flying saucer, steered by directing the downward airflow through a flexible skirt that allows easy directional control. The blades are not exposed and move reasonably slowly, it's stable in flight and the system is remarkably simple from a mechanical point of view. It's also quite simple to fly using a joystick controller. Totally VTOL and with a small footprint, perhaps the Entecho Hoverpod might deliver as a practical and affordable personal flight solution.
Entecho CEO Kim Schlunke is no stranger to out-there startups - he worked with Ralph Sarich on his revolutionary but ultimately doomed orbital engine in the 1970s and 80s, and more recently has been working on direct in-cylinder fuel/compressed air systems for two-stroke motors that can reduce fuel consumption and emissions by as much as 35%.
This latest venture is equally fascinating but perhaps more ambitious. Entecho's core IP is an odd enclosed-rotor flight technology that requires a disc-shaped aircraft with passengers or payload in the center. Yep, pretty much your classic flying saucer.
How it flies
Air is drawn into a ring of vents on the upper side of the aircraft, then forced downward through the rotors, which spin inside the shell of the aircraft. The resulting pressure differential lifts the aircraft off the ground and delivers effective VTOL capability with good hovering stability, even in crosswinds.
At the bottom of the craft is a flexible skirt which is controlled by releasing or pulling in a ring around the bottom of it. This directs the flow of air, and makes for a very simple and reportedly intuitive 360-degree steering process via a joystick. We're not sure how yaw will be controlled.
Top speed should be around 120kmh, and an initial range of 3km will improve through development.
The ducting that surrounds the inner pod, housing the rotating blades, is largely hollow, meaning that in the event of a crash, it will act as an enhanced crumple zone. The low blade speeds - around a fifth the speed of a conventional rotorcraft - help reduce both safety and environmental issues found in other rotorcraft.
We're not sure how the Entecho craft would fare in an engine-off emergency landing situation, but the initial plans for the manned Hoverpod would indicate that it's not going to be zooming around at high altitude anyway.
Entecho are building two models using the enclosed rotor technology. The first is the small, 11 pounds (5kg) unmanned Mupod, which can be used for a variety of UAV applications and measures 3 feet (60cm) in diameter. Entecho have already demonstrated a flying prototype of the Mupod.
The larger Hoverpod is a manned version with up to 3 seats. It's 5 feet (2.7m) in diameter and limited to fly 5 feet (1.5m) above ground - this doesn't make it the flying car everyone's holding out for, but it's a significant improvement on, for example, the standard hovercraft - and opens up a much wider range of passable terrains.
Entecho have also recently developed an attitudinal tilting system that allows the Hoverpod to tilt and develop translational g-forces in any direction, which should make it even more fun to fly as a recreational vehicle.
While the Hoverpod has been in development for several years, it's unclear whether Entecho have had a manned test flight of a prototype yet - but it's clearly in the pipeline.
A limited altitude of 1.5 metres won't satisfy our flying car desires just yet, but Entecho see the Hoverpod as more of a recreational vehicle to start with - and it's certainly capable of a broader range of terrains than a hovercraft. Would the same design reliably work at higher altitudes and speeds? We'll have to wait and see.