A case can be made for hybrids
Go on then...? Hybrid makes a lot of sense for road transport - most of the time only a fraction of the engine's total power is in use, plus you can recycle energy from braking. So you can have a much smaller engine, supplemented with an electric motor and a small battery. But for flying? The engines typically run at around 75% full power for hours and hours, so where do the energy savings apply?