UMX Conscendo Windy Lake Flight - 3S vs. 4S Battery Test & Epic Aerobatics!

[@shmaknapublar]

Removing thermal activity and slope lift from the equation, wind speed will have zero effect on flight duration. The aircraft simply has no idea that the air mass is moving and the amount of time in air vs the percentage of battery consumption will remain the same. This would make more sense to you if you ever flew freeflight models. Ask yourself if rowing a canoe upstream versus in a calm lake would increase the efficiency of your strokes, or just change the apparent distance traveled.

[@ReCoN12371]

I like the canoe analogy. It makes the concept of speed vs velocity and relative velocity vs ground speed more tangible.

[@InvertedAviatorsRC]

Hey, thanks for your input! I totally get where you're coming from with the idea that wind doesn't inherently change how a plane flies in an airmass, and I agree in most scenarios. However, I think we're talking about slightly different goals here. My goal when flying in the wind isn't to cover ground or fly from point A to point B-it's more about staying in one place, almost hovering, and gliding around with minimal effort. In this situation, when there's a strong headwind, the wind effectively becomes my source of lift. Since the airspeed over the wings increases (even if my groundspeed is close to zero), that airflow generates the lift I need to stay aloft, allowing me to use less motor power. It's similar to how a plane on a runway could take off with enough headwind, even though it's not moving forward on the ground. So while I agree that wind doesn’t directly reduce battery consumption when you're just flying around normally, in windy conditions where I’m trying to stay in one spot, the wind is helping by acting like an engine, keeping the plane aloft and extending flight time.

[@shmaknapublar]

@@InvertedAviatorsRC No. It is not. You are completely leaving out the increased drag component that comes with an increase in air speed. The only way to stay in one spot with increased air speed is to trade in some altitude or add thrust from the engine. We are talking very basic aerodynamic concepts. If you don't understand how airfoil lift to drag ratios change with the volume of air passing over them, your modeling science chops are the equivalent of having to use your fingers and toes to count to 20. Start by looking up drag polars and what's known as Reynolds number, then come back with some kind of reasonable explanation of how you are getting free lift without the penalty of increased drag just by turning the nose into the wind. Go to any rc sailplane competition and ask the competitors if your theory will hold water. It won't! And we fly the most advanced rc sailplanes that money can buy, exponentially more sensitive to energy losses in the hands of an experienced pilot. Windy days in no way increase your glide performance. That's totally reliant upon finding lift. There are many sources of lift, but you can't just hover in mid air, or even decrease your glide ratio by flying upwind. Sink rate is the same if the real air speed is the same.

[@shmaknapublar]

@@InvertedAviatorsRC This is a good concept to understand as well. Full scale competition soaring pilots have a very good understanding of how speed impacts glide ratios so they have special tools to determine how to lose the least amount of altitude given the estimated distance to the next source of lift and the drag profiles of their specific aircraft. en.wikipedia.org/wiki/Speed_to_fly

[@paulhope3401]

Just thinking out loud.. If you did not have a fpv cam, you would still have to keep the plane in view to fly it though so it's less about distance covered and more about keeping it in the air... that doesn't apply to a canoe. If the wind is strong enough to give it some relative airspeed and therefore lift, I'm thinking the energy used in both scenarios won't be the exact same. It probably wouldn't be very easy to measure, though. Sailplanes can fly with minimal throttle use and stay up for longer times on a windy day than a still one.... and this UMX conscendo is not so far off being a sailplane by design, lift/drag ratio etc.

[@alanpound5071]

It is a fallacy. Either a model, or a full-size, when flying in an air-mass, flies at whatever airspeed is appropriate to it. If the air-mass is moving relative to the ground, then that will affect the speed over the ground, but not the airspeed. It the airmass, there is no “lift” from simple wind speed (unless you are slope-soaring, where the contours if the ground will cause vertical movement of the air-mass - nhich is usually perceived as “lift”).

[@stevelhamon2031]

My night radian stays up forever in wind. Motor off 45 minutes of flight.

[@jamesturncliff5960]

Jay Bauer has a little device that you hook up to your night radian lights and then you can control the late unit from your transmitter

[@InvertedAviatorsRC]

@stevelhamon2031 woah! Yeah we’ve been looking into some other gliders, and that sounds awesome!

[@InvertedAviatorsRC]

@jamesturncliff5960 is that something like the led switch we have? It sounds really cool either way!

[@jamesturncliff5960]

@@InvertedAviatorsRC it hooks up to the switch that you have in your night radiant and a channel on your receiver what you will have to unlock or put a new receiver in the night radiant and you can control all the buttons that you can with a little dongle but through your transmitter by flipping switches

[@InvertedAviatorsRC]

Oh I see, that's pretty cool!