Plug and Play - And It's Good For The Environment

The crowd surrounded the small yellow Sonex plane at AeroShell Square, waiting for answers. Electric? Ethanol? What will Sonex Founder and President John Monnett would be announcing at Tuesday's press conference about his company's E-Flight Initiative?

Following company accolades by Tom Poberezny concerning the company's craftsmanship and its endeavors to improve and grow aviation in the future, Monnett took to the podium and made it officia --l by introducing the proof of concept prototype electric motor powerplant, controller, battery pack and charging systems installed in a Waiex airframe.

The proof-of-concept looks exactly like a Sonex from the outside, but uses the alternative energy source.

And for the ethanol crowd, he noted AeroConversion's investigation of converting its versions Aero Vee 2.0 powerplant for use of both ethanol-based fuels. More on that Wednesday, though.

The goal of the electric proof-of-concept, according to Sonex, is to determine the feasibility of a marketable line of Sonex and prototype products.

With the current Sonex staff focused on customer service and sales, it was only a small group of folks from AeroConversion who focused their energies on the new concept, which only took six months from idea to concept plane.

The current non-electric Sonex is a kit-based, basic all-metal two place monoplace suited for the US Sport Pilot.

And for those looking under the cowling to see which company's battery was being used in the proof-of-concept, they were disappointed.

Noted Sonex's Director of Public Relations Mark Schaible, the motor and battery system named no names: "They are proprietary parts we are in the process of developing."

The motor, said Schaible, is more than 90 percent efficient... and the most powerful of its kind. In regard to battery power, most contemporary electric powerplants for gas-electric and pure electric cars and previous generations of RC electric vehicles utilize Lithium Ion battery technology.

While much improved in power density and discharge rate over lead-acid and NiCad batteries, Li-Ion batteries still do not offer sufficient power discharge-to-weight ratio to support an electric powerplant for an aircraft based on battery power alone with market-viable endurance.

Newer RC electric vehicles, cell phones, laptop computers and other mobile devices have been moving toward Lithium Polymer cells, which can safely discharge at a rate of 25 times their capacity, or "25c."

The so-called "E-Flight Team" engineered and constructed 10 battery "safe boxes" to contain eight Li-Poly battery packs per box and consolidate their charge/discharge and balancing wiring into two sets of multi-pin connectors.

The boxes will accommodate natural cell expansion and contraction while safely securing each cell pack and facilitating cell cooling with "cooling foam" padding. The boxes are designed to contain and safely direct fire or explosion within the box through a "blow hole" in the box connected to a small exhaust manifold.

For the proof-of-concept plane, the battery boxes are removed and charged individually.

Further generations of safer, more powerful Li-Poly batteries show the near-term possibility of further extended flight durations, from the current 45 minutes to one hour, while personal electronics and transportation will undoubtedly continue to push improvement of the technology in years to come.

And now to the big questions. When will an actual kit plane be available to the public and how much will it cost? As with any proof-of-concept, company representatives were unable to share specific timelines

However, said Schaible, "We don't want to take too long and we don't want to put out artificial deadlines."

And in regard to price? "Any (final) product will be vastly less expensive than other things out there." In fact, said Schaible, the entire research and development for the project is less than the cost of a ready-to-fly LSA.

A follow-up informational forum is open to the public Wednesday, July 25 at 11:30 am at AirVenture forum building 11.

Founded in 1998, Sonex Aircraft has been providing a series of Sport Pilot-eligible kit aircraft and producing the AeroConversions' line of products that include Aero Vee engine, AeroCarb, and ancillary aviation products.

FMI: www.sonexaircraft.com/aircraft/sonex.html