Vortex Ring questions

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DrewFlies

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Does anybody know the actual rate of speed that causes vortex ring while descending? I noticed RTH descends a lot faster than me manually.
 
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If the rate of descent on the RTH is descending to fast I would take manual control before landing. One thing I doubt the auto pilot factors in is vortex ring and if this happens as your coming into land you want to be quick on the controls to increase forward airspeed and gain height again to negate the vortex ring effect and then reattempt your landing manually.
 
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Does anybody know the actual rate of speed that causes vortex ring while descending? I noticed RTH descends a lot faster than me manually.
It changes. Wind speed would have a great affect on this. The temp of the air would probably even affect it a bit. It's just not possible to know an _exact_ speed.
 
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You might want to get something like an X5C to learn what VRC looks like in various conditions.

When wanting to land fast I do a steep glidepath moving forward quickly.
 

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It changes. Wind speed would have a great affect on this. The temp of the air would probably even affect it a bit. It's just not possible to know an _exact_ speed.
+1... perfect answer...
 
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wind speed, air pressure and temp...density altitude, has a big effect. Props being used and weight of aircraft. It can change from day to day. Your quad will fly better in cool dense air than hot thin air.
 
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DrewFlies

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I have read about slightly moving the quad as your descending. But, when I do that it sounds like the motors are a lot loud and the angle the quad goes in makes me feel likes it more vulnerable to crash if all of a sudden there is a high gust of wind or something of that nature.
 
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DrewFlies

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If the rate of descent on the RTH is descending to fast I would take manual control before landing. One thing I doubt the auto pilot factors in is vortex ring and if this happens as your coming into land you want to be quick on the controls to increase forward airspeed and gain height again to negate the vortex ring effect and then reattempt your landing manually.
has there been any reported issues of RTH going into VRC?
 
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I have read about slightly moving the quad as your descending. But, when I do that it sounds like the motors are a lot loud and the angle the quad goes in makes me feel likes it more vulnerable to crash if all of a sudden there is a high gust of wind or something of that nature.
You need to try and understand this. It is simple so let's not make it difficult. An aircraft weighs a certain amount. The props, motors, battery power have to provide lift to get off the ground and hopefully more power to go out and do some serious flying. Now when the quad comes straight down with no wind, it may enter its own prop wash leading to VRS. That means it's flying in dirty air and may not be able to provide the proper lift for the craft. What to do? Add more throttle? All you do then is make more dirty air and the craft starts to decend in a uncontrolled manner. Loss of lift. Air is like water but thinner. A boat prop that cavitates can't get the thrust needed to get the job done. It needs clean water with no bubbles to push against to provide thrust. Same with the phantom in the air. Dirty air is kinna like bubbles in a way. If you move the quad sideways into clean air you regain your lift. The props need to push against good solid air rather than squishy bubble air if that makes any sense. If you do enter the VRS state and move the quad sideways...don't move with the wind, it just follows you. I can go fly my quad and take it high and bring it down fast at an angle always considering the wind direction. I can see when it starts to enter VRS. No big deal.Just get your *** into good air and fly. Forget some of the panic posts you see. So many have no clue what they are talking about. Just go out and test for yourself. You will learn more and become a better pilot. Good luck.
 
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You need to try and understand this. It is simple so let's not make it difficult. An aircraft weighs a certain amount. The props, motors, battery power have to provide lift to get off the ground and hopefully more power to go out and do some serious flying. Now when the quad comes straight down with no wind, it may enter its own prop wash leading to VRS. That means it's flying in dirty air and may not be able to provide the proper lift for the craft. What to do? Add more throttle? All you do then is make more dirty air and the craft starts to decend in a uncontrolled manner. Loss of lift. Air is like water but thinner. A boat prop that cavitates can't get the thrust needed to get the job done. It needs clean water with no bubbles to push against to provide thrust. Same with the phantom in the air. Dirty air is kinna like bubbles in a way. If you move the quad sideways into clean air you regain your lift. The props need to push against good solid air rather than squishy bubble air if that makes any sense. If you do enter the VRS state and move the quad sideways...don't move with the wind, it just follows you. I can go fly my quad and take it high and bring it down fast at an angle always considering the wind direction. I can see when it starts to enter VRS. No big deal.Just get your *** into good air and fly. Forget some of the panic posts you see. So many have no clue what they are talking about. Just go out and test for yourself. You will learn more and become a better pilot. Good luck.
Good explanation, No amount of power will solve Vortex ring and is a common mistake among pilots and the cause of some helicopter crashes, As a qualified Helicopter pilot if you still have height the only resolve is forward flight to get cleaner air. Thats why descending from high altitude forward and down, Always forward and down even when you are practicing auto rotations as its the safest way to avoid vortex ring in the first place. When you are low enough to the ground and IGE ( in ground effect ) then you can safely descend to land vertically.
 
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This will not be a problem. Plenty of power to pull it up anyways.
I don't know about the phantom but from my experience flying real helicopters adding more power actually makes it worse.
 
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