Over the past three years, tremendous progress has been made in pursuit of the AHS Igor I. Sikorsky Human Powered Helicopter (HPH) Competition, with a half dozen official registrants for the Competition. The NTS Works Upturn made its first flight on June 24, marking the second active program to get off the ground, after the University of Maryland’s Gamera.
NTS Works is a product development company led by Neal T. Saiki, who is responsible for developing a wide range of products such as aircraft, bicycles, EV batteries and motorcycles for more than 20 years. Saiki had been part of the 1989 student team at California State Polytechnic University at San Luis Obispo that built the first human powered helicopters to lift off the ground, culminating in “Da Vinci IV” – it flew for a record 8.6 seconds and a height of 8 inches.
Now, NTS Works has developed its Upturn HPH, also based on the reaction driven rotor principle of Da Vinci. The Upturn helicopter design had begun 15 years ago and construction has been ongoing for the past two years. (See Vertiflite Winter 2010 for more details on NTS Works and Upturn.)
The Upturn weighs 95 lb (43 kg) and has two rotor blades with a diameter of 85 ft (25.9 m), plus two orthogonal 48 ft (14.6 m) diameter blades with two tip-mounted 6 ft (1.8 m) propellers. The pilot powers the propellers, which rotate the two rotors.
Amateur bicyclist Robert Pasco was the pilot for the successful June 24 flight, which lifted off the ground for 10 seconds, climbing to about 2 ft (0.6 m) off the ground. Longer flight times are expected, as Pasco had previously competed in a bicycle race earlier in the day, in addition to three other flight attempts. “We were surprised when it lifted off and climbed straight up in the air so quickly. More importantly, it was stable. There are no words to describe how good that felt for everyone on the Upturn team,” said an elated Saiki.
Upturn uses a computer stabilization and control system for stability and safety aloft. Several issues with the custom designed onboard control system had prevented successful flights over the past several months, with the inputs fighting the pilot’s power output.
Saiki notes that the Upturn’s rotors are mounted above the pilot, reducing the dependence on ground effect. The Upturn’s blades are 5 ft (1.5 m) above the ground. He is bullish on the Upturn’s progress: “With the additional power that a professional cyclist can provide, we should be able to win the [AHS] Sikorsky Prize.”