I fly almost nothing with a stabilized receiver, but I am seeing more and more use of them by newish pilots at the local power field. I think there are some risks to flying with stabilized receivers that pilots should be aware of.
Simple stabilized receivers are not a replacement for a good pilot. They simply do not have enough data points to work with. They do not have air speed sensors, or detailed programming for the airframe they are flying. Instead they have a lot of generic code that mostly works for most stall resistant airframes.
The basic job for a stabilized receiver is this: Move the servos to return the model to the correct orientation.
The issues arrive when the airframe is out of normal flight configuration. For example, when models get very slow, the risk of tripping a stall is greater. The stabilized receiver doesn't have any way of knowing if it is approaching this danger zone, so will continue to issue commands as if it were in a safe zone. These commands can easily trip a stall or snap.
While the above may not sound like a big deal, this is where the stabilizers go really wrong. Unless they have really advanced programming, a stall is usually a very bad thing with a stabilized receiver. A good pilot knows the best way out of a snap or a stall is to get off the controls and let the plane reattach. But a stabilizer is not aware of the stall and simply sees changes that need to be corrected, so it starts throwing more and more correction at the problem.The end result typically is a full crash as the model is never allowed to recover from the stall situation.
Typically the foam models we see today are very stall resistant designs. I have occasionally been surprised that some newer pilots have no experience with a tip stall and have no idea how to get out of it. They do the same thing as a stabilized receiver and throw more control at the problem. (I almost think I need to design a trainer that has a nasty tip stall tendency just to help train pilots.)
Why worry about tip stalls? In aerodynamics NOTHING is free. The methods that make a plane stall resistant comes at a price. That price is performance. As a pilot progresses through the hobby they tend towards higher and higher performance models. I'd strongly suggest that if you are going in this direction you need to wean yourself off of stabilizers now. You need to learn how to fully fly the model yourself.
It is a bit of a comedy show at our local power field as I see more and more higher performance models being set up with stabilized receivers. Pretty sure they come factory with stabilized receivers from that big brand so many buy from. Lets just say these planes have some interesting flight habits. Most of the performance is wasted as they rely heavily on over powering the airframe to get any performance as they still have to have some stall resistance built into them since they are flying stabilized.
The fun really kicks in when a stabilized receiver is added to an airframe that is not stall resistant. That receiver will simply lock you into a stall all the way to the ground.
We get more and more reports of people describing the same thing with stabilized receivers. Plane is flying along and suddenly just drops from the sky. Upon arrival at the crash, the radio gear all seems to be working fine. The radio gave no warning about lost radio connection, etc. I do think this is the result of the stabilizer doing its job, move servos to return the model to the correct orientation, but the plane entered a stall and the stabilizer controls locked it into that stall.
Stabilizers can be a great and useful tool, especially for very tiny models. But for larger or higher performance models, I think they are a rather horrible idea.
The Carbon Flacon we make is a VERY stall resistant design (pretty sure it has no stall). I'd very much like to try it out with a stabilized receiver as the super light wing loading means it is easily upset by tiny puffs of air. It should be a safe combination.
What has your experience been? What have you seen from flying buddies? I think this is a discussion that is long overdue.
Simple stabilized receivers are not a replacement for a good pilot. They simply do not have enough data points to work with. They do not have air speed sensors, or detailed programming for the airframe they are flying. Instead they have a lot of generic code that mostly works for most stall resistant airframes.
The basic job for a stabilized receiver is this: Move the servos to return the model to the correct orientation.
The issues arrive when the airframe is out of normal flight configuration. For example, when models get very slow, the risk of tripping a stall is greater. The stabilized receiver doesn't have any way of knowing if it is approaching this danger zone, so will continue to issue commands as if it were in a safe zone. These commands can easily trip a stall or snap.
While the above may not sound like a big deal, this is where the stabilizers go really wrong. Unless they have really advanced programming, a stall is usually a very bad thing with a stabilized receiver. A good pilot knows the best way out of a snap or a stall is to get off the controls and let the plane reattach. But a stabilizer is not aware of the stall and simply sees changes that need to be corrected, so it starts throwing more and more correction at the problem.The end result typically is a full crash as the model is never allowed to recover from the stall situation.
Typically the foam models we see today are very stall resistant designs. I have occasionally been surprised that some newer pilots have no experience with a tip stall and have no idea how to get out of it. They do the same thing as a stabilized receiver and throw more control at the problem. (I almost think I need to design a trainer that has a nasty tip stall tendency just to help train pilots.)
Why worry about tip stalls? In aerodynamics NOTHING is free. The methods that make a plane stall resistant comes at a price. That price is performance. As a pilot progresses through the hobby they tend towards higher and higher performance models. I'd strongly suggest that if you are going in this direction you need to wean yourself off of stabilizers now. You need to learn how to fully fly the model yourself.
It is a bit of a comedy show at our local power field as I see more and more higher performance models being set up with stabilized receivers. Pretty sure they come factory with stabilized receivers from that big brand so many buy from. Lets just say these planes have some interesting flight habits. Most of the performance is wasted as they rely heavily on over powering the airframe to get any performance as they still have to have some stall resistance built into them since they are flying stabilized.
The fun really kicks in when a stabilized receiver is added to an airframe that is not stall resistant. That receiver will simply lock you into a stall all the way to the ground.
We get more and more reports of people describing the same thing with stabilized receivers. Plane is flying along and suddenly just drops from the sky. Upon arrival at the crash, the radio gear all seems to be working fine. The radio gave no warning about lost radio connection, etc. I do think this is the result of the stabilizer doing its job, move servos to return the model to the correct orientation, but the plane entered a stall and the stabilizer controls locked it into that stall.
Stabilizers can be a great and useful tool, especially for very tiny models. But for larger or higher performance models, I think they are a rather horrible idea.
The Carbon Flacon we make is a VERY stall resistant design (pretty sure it has no stall). I'd very much like to try it out with a stabilized receiver as the super light wing loading means it is easily upset by tiny puffs of air. It should be a safe combination.
What has your experience been? What have you seen from flying buddies? I think this is a discussion that is long overdue.
