why can this drone fly 3 hrs & my P4P+ only ~20 min per charge???

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is it all about weight difference?
 
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I find this amazing science. The air molecules get stretched on top of the wing, effectively sucking the aircraft up. (2)
But this is the real amazing thing, because of this lift concept a body with an aerofoil shape can go faster than the wind behind it. It takes me ages to explain this to students, they just don't believe me at first.
I asked a guy called Joe on a land sailer this question two weeks ago and his reply was "Sh** yeh, more than twice the speed" I don't know the actual speed ratio it can be, but it's obvious on airborne, landborn and seaborn. Those sailboats way exceed the speed of the wind behind them. It defies logic in a way but so true.
Put your hand out of the car window, point your fingers directly towards the direction of the car then lift the tips of your fingers up and your hand will rise that is the air pressure underneath. (3)
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Fixed wings almost always fly longer. Makes me jealous. But a fixed wing can't fly backwards! [emoji78]
 
Fixed wings almost always fly longer. Makes me jealous. But a fixed wing can't fly backwards! [emoji78]

My P3P will give me a good 18mins flights ... but most of my electric fixed wing models are dead at 10mins ...

Backward flight ? It can relative to ground if wind is strong enough ... I regularly do backward flight on my parkfly jets and 3D gear. Prop thrust keeps it up ... control surfaces are large enough to use the prop wash ... bingo - 'impossible' flight
 
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is it all about weight difference?

No ... its about wing area and wing loading. Flying wings are able to carry large battery loads but still maintain a low wing loading. The lower that loading - the better the wing will glide. The Parrot uses power assisted glide to get the long flight times.
I have powered flat field gliders that I can basically stay up for hours if necessary by assisted glide. Unlike the P3 / P4 etc. - the motors are only used to maintain flight motion forward, which means they can switch on / off as needed ... even when on - the wing is providing the lift sufficient to stay up, while prop is pulling it forward. Don't forget also that gravity plays in this ...
Gravity pulls the model down ... but the wing design causes the model to then move forward. The pilot resists urge to level the nose and speed increases, as it increases - the wing develops more lift. This makes the glide slope extend significantly. Its the mechanism of all slope soaring / gliding ... add a motor and prop and you have tremendously improved flight capability.
 
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is it all about weight difference?
As others have stated, you are comparing the proverbial apples with oranges. In this case you are comparing a copter with a glider. Your P4P needs to constantly generate lift by using battery power. If the rotors were to stop, it falls like a rock. The glider generates lift through the wing (or in this case the entire body since it is basically a flying wing). If you turn off the prop, it will still glide. So there is no way that your P4P could ever compete in time aloft/battery power.
 
The air molecules get stretched on top of the wing, effectively sucking the aircraft up.
I would tend to disagree on this point from a very precise technical point of view. The molecules themselves are not "stretched". They are molecules and remain the same size. What happens is that the air density decreases above the wing. There are less molecules per cubic meter above the wing than there are below the wing.
 
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Thanks for responses.
Fixed wing also can't hover, right?
Best still shots taken with drone still, too.
What about combo drone-winged craft
in order to increase battery time...?
Fixed winged only for craft movement,
propellers only for hovering...?
Do these kinds of crafts already exist?
Related, is a helicopter significantly
less fuel efficient than a plane...?
 
Thanks for responses.
Fixed wing also can't hover, right?
Best still shots taken with drone still, too.
What about combo drone-winged craft
in order to increase battery time...?
Fixed winged only for craft movement,
propellers only for hovering...?
Do these kinds of crafts already exist?
Related, is a helicopter significantly
less fuel efficient than a plane...?
Do you mean like this?
 
Fixed wing + helicopter = Osprey. There are a couple "tilt motor" type drones out there net the best of both worlds, but they are expensive.

I found a cheapish one from Walkera.

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D
 
Physics.
 

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