For once, here is a propellers comparative test, detailled and on a long period.
On 11 July 2020, 2 single-seater Ellipse-Delta tilting Ellipse-Delta Alizé trike / wing MysticCX with 36 hp Swissauto 250 engine flew from Dunkerque (LFAK) to Oloron (LFCO) 906 km away (in direct line).
The two aircraft are strictly similar, loaded and equipped identically with 25 litres + 2 x 15 litres of extra fuel (total 55 litres), the pilots weighing 80 and 58 kg respectively, resulting in a take-off weight of 240 kg compared with 228 kg (for a maximum take-off weight of 245). The heaviest, Jean-Claude, opted for a 3-blade E-Props propeller and the lightest, Blaise, for a 3-blade Helix.
The E-Props propeller is the winning option, since despite the weight handicap, Jean-Claude landed with 14 litres of unused fuel which, at an average rate of 3.42 litres/hour, would have allowed him to fly another 3 hours with 1 hour of safety, i.e. a distance of 200 km… Blaise, with his Helix propeller, consumed 7 litres more, bringing his hourly consumption to almost 4 litres.
So, in this configuration and all parameters being equal, using an E-Props propeller saved 13% of fuel. Rather interesting !