>This isn't like a hybrid car. It's a parallel hybrid, where the gas engine is just big enough for efficient cruise at altitude, and the electric motor/generator provides extra power for takeoff and ascent (or go-around power), and then charges slowly during cruise if needed.

Isn't that exactly what hybrid cars (e.g. Prius) are? Extremely efficient gas engine for highway cruising, but insufficient for acceleration, which is aided by electric motors?

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Tade0 2 hours ago | parent | next [-]

The Prius uses a planetary gear set to blend power of the engine with that of the two motor-generators.

Both the engine and motors are used at all speeds. Particularly during highway acceleration the entire assembly rotates in the same direction.

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dgfl an hour ago | parent [-]

This is a great related watch if you have some time to kill: https://youtu.be/KnUFH5GX_fI

	▲	delecti an hour ago \| parent [-]
		That's such a fantastic video. I never totally grasped why hybrids were so much more efficient, because my naive assumptions about how they worked were so simplistic. The real-time graphs he showed were excellent for making his points.

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arijun 2 hours ago | parent | prev [-]

The Prius is in series, or something like it.

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idontwantthis an hour ago | parent [-]

No it’s not. The majority of power comes from the engine. It drives the electric motor mechanically, using it as a transmission. It is not just charging the battery.

	▲	arijun an hour ago \| parent [-]
		Sorry, I meant in the low speed, high acceleration regime (maybe easily confounded with takeoff?). There the engine will turn one motor to generate electricity, which will then power the second motor, like a series hybrid.