yeah nice job videoing it. I actually had a Conscendo disappear on its maiden a couple weeks ago when it went edge-on, and off it flew. I got a call from the neighbors farm later that day that it had crashed in their cherry tree, and I got it back mostly intact. Apparently when it lost radio contact it began circling, and came down.
You guys made me finally pull the trigger and buy a gps like yours. Its obvious even experts have a hard time 'eyeballing' a plane and guesstimating its speed.
Very weird that at it's terminal velocity the prop acts as an air brake, or at least doesnt accelerate the plane. I'm sure some aeronautic engineer could explain what happened.
Not an engineer here, but I think it’s a prop set up for efficient climb power at lower speeds. It takes a small bite of air and spins easily, where a high-speed prop takes a big bite of air and requires more power to spin. More advanced full-scale prop planes like a warbird or turboprop have a variable pitch prop that can be configured for climb or high speed cruise, like changing gears in a car. A prop like this is basically banging off the redline and not doing much for you at high speeds, if that makes sense.
Several factors, but perhaps the most pertinent (and what Tommy is describing in part) is the relationship between voltage, motor KV, and propeller twist. Voltage * KV = unloaded max RPM. In other words, the speed the motor spins at with no prop attached. The twist measurement of a propeller tells you how far forward the airscrew 'screws' in one revolution with zero angle of attack (what tommy calls bite) RPM * twist = The speed at which the propeller entirely unloads and stops producing forward thrust. Worth noting in level flight your aircraft top speed will be lower than this theoretical because drag is going slow you down, put angle of attack into the airflow over the prop loading it, which will push the motor down from max unloaded RPM and into a part of it's power curve where it can generate enough torque to balance said drag. One can imagine that there would be an angle where gravity is doing enough work to just overcome that drag and the plane would start to accelerate past the theoretical limit of thrust production and then the airflow starts to generate negative angle of attack on the prop and starts to spin it even faster. This acceleration costs energy in the form of increased drag. In this angle of dive you can see that the plane could well be faster with the engine off as the propeller, spinning so fast the motor is no longer putting down power, makes more drag deployed than lying flush with the body.
Interesting result powered vs unpowered! I’m guessing that the prop is more of a high thrust setup for quick climbing than a high speed setup. At full power in a dive it’s probably just banging off the redline and creating drag more than anything. 95 mph unpowered is pretty damn impressive in my book! Great video!!!
Ooooooooohh!! It sounds like a masterfully honed katana when diving on inertia!! But it really only has two speeds I'm afraid. Sitting still and... WHAT THE HECK WAS THAT!?!?!? XD
Кино
Awesome job guys! Great video Jeff, that thing gets small FAST in a camera lens!
yeah nice job videoing it. I actually had a Conscendo disappear on its maiden a couple weeks ago when it went edge-on, and off it flew. I got a call from the neighbors farm later that day that it had crashed in their cherry tree, and I got it back mostly intact. Apparently when it lost radio contact it began circling, and came down.
Great video fellas!! Nice plane, but hard to keep in the camera with those great skys, thanks for sharing 👊🏼👊🏼
You guys made me finally pull the trigger and buy a gps like yours. Its obvious even experts have a hard time 'eyeballing' a plane and guesstimating its speed.
Sno you like the way it flys!
great job guys
Very weird that at it's terminal velocity the prop acts as an air brake, or at least doesnt accelerate the plane. I'm sure some aeronautic engineer could explain what happened.
Not an engineer here, but I think it’s a prop set up for efficient climb power at lower speeds. It takes a small bite of air and spins easily, where a high-speed prop takes a big bite of air and requires more power to spin. More advanced full-scale prop planes like a warbird or turboprop have a variable pitch prop that can be configured for climb or high speed cruise, like changing gears in a car. A prop like this is basically banging off the redline and not doing much for you at high speeds, if that makes sense.
Several factors, but perhaps the most pertinent (and what Tommy is describing in part) is the relationship between voltage, motor KV, and propeller twist. Voltage * KV = unloaded max RPM. In other words, the speed the motor spins at with no prop attached. The twist measurement of a propeller tells you how far forward the airscrew 'screws' in one revolution with zero angle of attack (what tommy calls bite) RPM * twist = The speed at which the propeller entirely unloads and stops producing forward thrust.
Worth noting in level flight your aircraft top speed will be lower than this theoretical because drag is going slow you down, put angle of attack into the airflow over the prop loading it, which will push the motor down from max unloaded RPM and into a part of it's power curve where it can generate enough torque to balance said drag.
One can imagine that there would be an angle where gravity is doing enough work to just overcome that drag and the plane would start to accelerate past the theoretical limit of thrust production and then the airflow starts to generate negative angle of attack on the prop and starts to spin it even faster. This acceleration costs energy in the form of increased drag. In this angle of dive you can see that the plane could well be faster with the engine off as the propeller, spinning so fast the motor is no longer putting down power, makes more drag deployed than lying flush with the body.
I just bought this today can't wait to fly it myself 😎🤙 subscribed 😎
Thanks for the Sub!!! Make yourself at home!! And you'll love the Xv2!
Awesome!
That’s a really great plane. It needs more color because it really got camouflaged against the sky.
I put in a carbon laminate vacuum bag the wings and the dynamic soaring with it at 175 mph.... Mt. Perkins....
Very very cool!
Does your Excalibur likes to climb at 3/4-full throttle? If so, how did you correct this behavior?
Thanks linden!!!
Did you fly it with 3 or 4s?
Interesting result powered vs unpowered! I’m guessing that the prop is more of a high thrust setup for quick climbing than a high speed setup. At full power in a dive it’s probably just banging off the redline and creating drag more than anything. 95 mph unpowered is pretty damn impressive in my book! Great video!!!
Thanks! Aerodynamics of this plane are wicked cool!
Is your excalibur still working? My motor burnt up on 2nd flight and Hobbyking basically told me tough sh.. No warranty on anything. Anyone else.
Yeah mines still trucking along! I've flown it many times on 5s too.. So far so good
SOME SERIOUS BIRD 🐦 POWER RIGHT INTO THE BLUE
Yes sirrr to the moon!!
Which radar gun is that? Thanks.
That's a Bushnell radar gun 🔫
@@RCPlaneReviewer Thanks. We're going to have a SPEED contest at our club. Just maidened the v1200 ..... wow!
Hello 👋.
Ooooooooohh!! It sounds like a masterfully honed katana when diving on inertia!!
But it really only has two speeds I'm afraid. Sitting still and...
WHAT THE HECK WAS THAT!?!?!?
XD
🤣