On Aug 8, 2:21 am, Larry Dighera wrote:
I see what you mean. Unfortunately, the highest power requirements of
aircraft engines are during the takeoff and climb phases of flight.

Hence why i was thinking more along the lines of a electric motor +
reasonable battery coupled to a stirling. The battery provides the
oompfh for takeoff (and other moments of urgency) from stored energy.
The stirling charges the battery, or passes current through to the
motor when the battery is at peak charge (hand waving the bajillion
technical details which I don't know), it doesn't matter that the
stirling doesn't run at peak efficiency at all times, in cruise mode
you'd want it to be at peak and providing more than enough current to
the motor with some spare to charge the battery.

The article I linked to was more along the lines of a direct-drive,
but I think hooking the output shaft from a stirling straight to a
gearbox/prop would not be a good idea, you are stuck with too many
disadvantages and it makes the engine design more complicated than
necessary.

The main advantage of the stirling+battery versus just battery, is
that you remove the requirement for major infrastructure change
(abundant charging points at airports), the stirling just needs some
fuel (which could be anything from mogas to radiant solar heat) and
that's it, no infrastructure change is necessary in the interim, and
minimal in the long term. As an added benefit, you get much better
cruise endurance than battery alone.