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Lilium claims to fly with "electric jets". Throwing out the debate over whether a non-combustion compression of a stream of air is a jet or only a ducted fan, what is the potential thrust each of these could be getting?

Edit: since it's not compressing, what potential lift could the Lilium prototype engines provide, and are there examples of electric engines today that provide compression in a significant way?

Ignoring the stability issue of Lilium as well. Just curious about the ducted fan design they have. Also ignore the problems with it being electric and battery powered please :)

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    $\begingroup$ Full marks for the marketing guys at Lilium. What a great scheme, to call it an electric jet instead of a garden variety household fan. I reckon the range of the Lilium is only limited by the length of the extension cord. $\endgroup$ – Koyovis May 28 '17 at 14:56
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    $\begingroup$ There is no way that design creates any kind of meaningful compression, ignoring the fact that the rapid expansion by burning fuel is the main reason for compressing the air in the first place... $\endgroup$ – Ron Beyer May 28 '17 at 16:28
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    $\begingroup$ Related, if not duplicate: Could an electric engine provide the same performance as jet engines on current aircraft? $\endgroup$ – mins May 28 '17 at 16:56
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    $\begingroup$ Please edit your question instead of asking in comments. $\endgroup$ – mins May 28 '17 at 17:08
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    $\begingroup$ Also, not a duplicate mainly because I'm curious what thrust these specific engines could currently be providing. $\endgroup$ – oeste May 28 '17 at 17:10
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They look like 15 cm fans, thrust of which is competently ROM-ed in this answer.: about 40 to 60 Newton.

Note that the $C_T$ in the equation depends on fan solidity, the higher the number of blades and the wider they are, the more thrust they produce, but also the higher power required. For a given fan power (and battery life) it makes more sense to increase fan diameter and decrease fan solidity.

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Does anyone know what the diameter is of Lilium's ducted fans? Cause that co-determines vtol ability and efficiency!

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