A while back, we wrote about the latest hot news concerning electric aircraft that were under development, and I noticed that one of them had a back-up generator as a range extender (to see that article, click here). I have friends that think a hybrid is the “worst of both worlds” but as I’ve said before concerning EV cars, I still believe that a hybrid drivetrain is a viable option for the next decade, or at least it is in some applications (to see our hybrid EV article, click here).
Well, I recently began seeing lots of announcements about hybrid aircraft under development. These still have the major benefits that electric planes have, such as a much quieter take-off at small municipal airports, along with reduced exhaust emissions. Another major factor driving small electric aircraft development is the potential fuel savings, and also the maintenance costs of engine-rebuilding after it has reached its maximum safe life, since electric motors can run many more years before a rebuild. By the way, when a brushless electric motor does eventually need a rebuild, its pretty much just replacing two shaft-bearings!
It appears that the current drive to spend some effort and money on a hybrid plane is due to certain businesses wanting to get busy flying an alternative powerplant much sooner, instead of waiting any longer for certification of a pure EV plane. We recently wrote about the new developments in battery chemistry, and even though I now feel comfortable saying that the new chemistries will be here “soon”, I know that battery labs have been saying this for a decade.
And this brings us back to hybrids. Aircraft will still definitely take advantage of the new batteries when they become available. You know, the ones with super-fast charging, and twice as many miles per volume. However, its pretty easy to use off-the-shelf components to create a hybrid plane, and a few companies feel that this is the path forward for their near future.
When accelerating for takeoff, a plane’s engines are run at full power. But once they begin cruising along at a level altitude, their cruise setting uses much less power. This means that when a hybrid plane has the impressive torque of an electric motor for the take-offs, the range-extending engine/generator can be much smaller than the size of engine that the plane might normally require.
