Ulm and light aircraft of the future

[chatelot16]

for fuel there is ethanol, but that contains only 0,8 times the energy of the same weight of gasoline

also you have to keep the real essence for the flying machine and put ethanol or vegetable oil in the car!

other detail: the paramotor is 2 time ... the mineral oil or synthesis does not mix with ethanol ... so it should be a pump like some motorcycle

or you have to use castor oil, which mixes well with ethanol or methanol ... I would have liked to do it for a tronconeuse ... except that castor oil is so expensive that it's completely without interest

I wondered if the E85 that contains 15% gasoline does not contain enough gasoline to dissolve the oil of the mixture 2 time: the answer is no, with synthetic oil and E85 the mixture remains cloudy, a tronconeuse walks without seizing, but never works well: impossible to regulate correctly the carburettor

I have a derbi 50cm3 which has an oil pump that works very well at E85

[Cuicui]

the batteries are heavy: for a land vehicle it weighs already on the performance ... for the flying machine it is a catastrophe: it does not even allow to have the minimum autonomy imposed by certain regulation

50 minutes still for the Paracell AIRFER. Total weight 28 kg including 12 - 16 kg of batteries. 12.800 €. It only remains to adapt the regulation ...
http://www.airfer.fr/PBProduct.asp?ItmID=8011572

[gegyx]

funny, but will have to plan the change of "trailer"

[Remundo]

it is a bit strange this plane imitating the hunters.

surely fun, but the aerodynamics so so.

when I see that poor propeller at the back surrounded by turbulent obstacles.

and the fairing as a whole is not suitable for low speed light aviation flight.

[Christophe]

This one is more better:

[Remundo]

An interesting question about the arrangement of the 2 seats.

Finally the seats side by side do not seem more penalizing, an explanation of Michel Kieffer found on this thread

Mathematical notations of the terms below:

Ro = air density = 1,2 kg / m3 (on the ground)
V = speed in m / s
SMT = total wetted area
SM = wet surface
Cfe = equivalent coefficient flat plate
m = mass
g = 9,81 m / s2
P = power in watts
Rh = propeller or propulsion efficiency

Chatelot, side by side or tandem?

The fundamental equation is:

Equation: P.rh = ½.ro.v3 (SMT.Cfe + drag induced by lift)

At cruising speed, the drag induced by the lift is low compared to the SMT.Cfe product. We are therefore more interested in the SMT.Cfe product

See the explanations in the document " how to achieve our goals » http://cocyane.chez-alice.fr/aeronautique.html
See definition of these terms below.

Unlike the automobile, which references the aerodynamic efficiency coefficient (CEA) "Cx" to the frontal projected surface S, in aeronautics, we refer to the CEA "Cfe" to the wet surface SMT. However, the S.Cx product is identical to the SMT.Cfe product

So, tandem or side by side?

Insofar as the aerodynamics are correct (no flow of the boundary layer), the Cfe of these 2 config are identical, the difference will then be made on the SM of the fuselages. We deduce that the best configuration is that which leads to the minimum SM. Let's determine the SM tandem fuselage and side by side, well, we get pretty much the same thing. In one case, we are narrower but the fuselage is longer, in the other case we are wider but the fuselage is shorter.

Conclusion: in terms of aerodynamics, side by side or tandem, it's the same!

There remains a configuration that saves 10 to 14% of the fuselage SM: the side by side offset by 0,3m, which allows to significantly reduce the width of the aircraft without extending the fuselage too much. That said, 10% on the fuselage represents about 3% on the SMT (total wet surface), so nothing to revolutionize the subject ... We must act on other things.

Michel

[gildas]

An electric version may be considered on the Risen:

" I believe
much to electric aviation,
the Risen could perfectly be
equipped with an electric motor but
be patient, he is humanly
impossible to fight on all
foreheads at the same time. »

https://www.flyrisen.com/imag/galleryre ... ober17.pdf

Because of the responsiveness of electric motors, could runways be created more easily? An engine in each wing for a very short takeoff and moderate reversal of the direction of rotation of the propellers once on the landing strip?
Fast and serious?

[Macro]

All this for the modest sum of €180 in its basic version...

Damn where is my check book... It's going to make a little hole in my booklet A But hey, you have to know how to have fun from time to time...

[Remundo]

even well designed and attractive, this kind of plane is boring, it takes airfields to take off and land.

once in the air, okay, we have fun.

they are built in very small series, therefore very expensive.

their side ? I'm afraid that on €180 new you lost 000% from the first flight... no ?

As for the electric versions, these are small jokes to turn 30 minutes around an airfield. it can have its user niche (Sunday pilot, apprentice pilot). But on a serious trip, it's dead.

[Macro]

20% lost on the first flight. Then the maintenance... Let's say at least 10% of the initial price every year... The coco has to be put in the tank... No more than a sedan per 100km...