The First Electric, Manned and Untethered Helicopter Flight

A French engineer makes his way into history with an electric helicopter prototype all his own.

Electric Helicopter
Electric Helicopter
**The French company known as Solution F recently asked engineer and pilot Pascal Chretien to undertake the task of building an electric helicopter. A year later, he completed the first electric, manned and untethered helicopter flight in his own prototype.
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Electric Helicopter Flight
Electric Helicopter Flight
While backed by Solution F, Chretien designed and built the prototype largely on his own. It took him approximately a year to complete. Chretien is shown here working on the helicopter.
Electric Helicopter Flight1
Electric Helicopter Flight1
Chretien chose an ultralight, coaxial rotor design to get the job done.
Electric Helicopter Flight
Electric Helicopter Flight
The prototype's rotors are powered by lightweight, brushed DC motors, as well as highly flammable Lithium ion polymer pouch cells.
Electric Helicopter
Electric Helicopter
**Despite the helicopter's other unconventional aspects, the lithium batteries pose the greatest risk during flight.
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Weight-Shifting System
Weight-Shifting System
As opposed to cyclic control systems used in conventional helicopters, Chretien chose a simple weight-shifting system to provide steering capabilities. The lever arm shown here controls the system, as well as the collective.
Weight-Shifting System
Weight-Shifting System
A computer-generated illustration of the helicopter's weight-shifting system is shown here.
Electric Helicopter Test Seat
Electric Helicopter Test Seat
**Chretien used this test seat to acclimate himself to the unusual design, which required him to overcome long-ingrained habits acquired during his 15 years of experience flying conventional helicopters.
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Yaw Control
Yaw Control
Like in traditional helicopters, yaw is controlled through the prototype's pedals.
Electric Helicopter
Electric Helicopter
**All of the prototype's components come together to form a lightweight design focused on energy efficiency.
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Electric Helicopter Flight
Electric Helicopter Flight
A computer-generated design of Chretien's design is shown here.
Electric Helicopter Flight
Electric Helicopter Flight
**Chretien tested this design with several tethered flights earlier in the year.
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Electric Helicopter Flight
Electric Helicopter Flight
During those fights, Chretien was able to evaluate his weight-shifting system as well as certain other aspects of the helicopter, such as the aircraft's ground effect behavior.
Electric Helicopter
Electric Helicopter
**While some successful strides have been made in the area of electric airplanes, advancements in electric helicopters have been limited. But Chretien and others, such as Sikorsky, which unveiled its Project Firefly electric helicopter demonstrator last year, are working to change that.
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Electric Helicopter Flight
Electric Helicopter Flight
Since helicopters require a great amount of power during several key phases of flight, including landing, the risks of testing an all-electric machine are great.
Electric Helicopter Flight
Electric Helicopter Flight
**Despite those risks, Chretien successfully achieved the first electric, manned and untethered helicopter flight last month.
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Electric Helicopter Flight
Electric Helicopter Flight
Staying approximately one meter off the ground, Chretien flew his prototype untethered for a little more than 2 minutes.
helo18.jpg
**To learn more, check out our feature story on Chretien's flight.
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