An awesome idea from Spain: hybrid airplane powerplant. Airplanes need about 65 percent power for a reasonable cruise. Airplanes can certainly fly on 35 percent power. Thus having an electric motor that can be used for a boost on take-off and as a backup in case the reciprocating contraption comes apart comes with potential weight savings as well as some potential safety improvements (though not too many accidents are caused by power failure).
With typical regulatory certification challenges this might be ready in 10 years!
This makes too much sense to be successful. Chances are it will never get off the ground (pun intended).
The Spanish are not well known for aviation, at least not since the days of Juan de la Cierva. Cierva died young in an aircrash, but not one of his autogiros, but on an ordinary commercial flight. The flight took off in fog and they used the following high tech method of instrument flying : they painted a white line pointing roughly west on the grass field which was later to become Gatwick Airport. If the plane followed this line and climbed at a normal rate, all would be well. However, Cierva’s plane veered off the painted line to the left and took off on a heading toward the southwest where there was a hill. The plane hit the chimney of a house on the aptly named Hillcrest Road and crashed, killing 15 of 17 on board including Cierva.
A non-trivial number of accidents result from running out of fuel – the hybrid may have good potential there, but I don’t see any manufacturer like Tesla in the general aviation industry. Likely to die on the vine except for some homebuilts.
I saw this recently as well and like the idea. But I wonder if by the time it gets through the regulatory burdens if battery technology will be advanced enough for a fully functional electric plane?
On a related note, your thoughts on the multiple-engine electric plane?
http://www.nasa.gov/aero/testing-electric-propulsion.html
Rob: I would like the multiple-engine idea if it resulted in lower interior noise. Having one big prop with tips going near the speed of sound seems to be a recipe for unpleasantness.
Phil,
what about a hybrid piston/electric engine helicopter with a configuration like the honda accord plug-in hybrid where the electric motor replaces the transmission? For start-up, clutch is open and piston engine drives a generator. The electric motor turns the rotor. when RPMs are sufficient, clutch engages and electric motor free-runs. In event piston engine cuts out, electric motor engages, powered by a battery pack that gives you 2-3 minutes of flight time.
Phil,
I am building a plane in my garage that incorporates this very idea. It is called the ski gull and can land and take off on any surface. It will be powered by a rotax engine and use 2 electric engines to assist take off. Also the plane can be flown for a short time on just the electric engines.
Here is a little write up about it from aopa
http://www.aopa.org/News-and-Video/All-News/2015/March/16/Rutan-SkiGull
The great thing about experimental aviation is we do not have all of the silly and usually unnecessary government regulations. But as you have pointed out in the past our accident rates are higher than the certified world. My goal is to fly the ski gull nonstop to oshkosh this year from Idaho.
Wow, that was THE Burt Rutan….
One of the reasons hybrids work in automobiles is that you can recover energy from regenerative braking, since cars stop so often. There are far fewer opportunities to recover energy in a hybrid plane.
It sound’s like Mr. Rutan’s idea is a little different – he is using separate folding props for his electric motors, whereas the Spanish electric motor appears to be on the same shaft with the gas engine and drives the same prop.
I wonder if you could do a Chevy Volt type setup where the prop is primarily driven by an electric motor and a small battery but there is a gas powered generator to keep the battery charged. The gas engine could also be set up to drive the prop directly in case the electrics failed.
Thanks, Burt, for the comment. The SkiGull does sound like perhaps the first truly practical amphib for the average pilot. Docking a regular seaplane, for example, requires skills that hardly any pilots have. It also sounds as though perhaps you’ve solved the “wheels down in water flip” problem to which the Icon A5 will presumably be prone (see http://philip.greenspun.com/flying/icon-a5-seaplane ). The one thing that I learned from getting my seaplane rating is that I could not operate the then-current generation of seaplanes safely!