ORIGINAL: JohnMac
Correct information is subjective, depending on the use to which it will be put. Technically it is correct to say that you can fly a plane slower with the cg at its rearward limit (which is in itself subjective), but how useful is it to know this in isolation? Indeed, in isolation this fact may lead a pilot to believe that a rearward cg is safer.
I my experience, if I am flying a model that "feels" tail heavy, I trim it down to make it fly faster since I have NO IDEA what its airspeed is. Moreover, any departure from the specific set of condition will change the speed that the aircraft will stall, and even the mode in which it will stall. Change the wing loading, angle of bank, flap or slat position etc, aileron or rudder input, all will change the speed of the stall.
Since the model pilot cannot be accurately aware of many of these conditions, he must fly the model by visual cues combined with being aware of his own stick inputs to judge when then model will stall, and by so doing avoid it. This is the model pilots version of the truth!
WMB has provided us a good example of what can happen if you move the CG too far back, and this is, I suspect with a lightly loaded model.
I reiterate that nose heavy aeroplanes do not fly very well, but tail heavy aeroplanes do not fly very long.
John
You got excellent points there. And in the modeling world, too many have come to believe that a nose heavy model is safer. It is not.
Add this to those good points.
There probably aren't 20 model flyers in the world who can make use of the difference in speed IF it happens. First off, nobody can tell the difference between the model flying at 18mph and it flying at 20mph. And that's about how much the change in speed is going to be. Secondly, there aren't too many modelers who can accurately take their model airplane right up to the max CL and hold it there, just under the AOA of the stall. And thirdly, no modeler alive can see what the windspeed is around the models, so flying at the last few degrees of AOA is just not going to happen safely, since gusting is one of the major problems to safe landings.
Wringing the last bit of performance out of any model is fun, but this one is simply out of the model flyers' capabilities. We can gain a few mph for sure, but using it accurately just isn't going to happen. Using it at all really isn't either.
In practice, the best way to get a model to land more slowly with safety is to tune the engine to idle more slowly with dependability and to put a flatter pitch prop on the sucker. And even that is degraded when the CG is farther forward than optimum. Get the CG adjusted to the optimum for control and then work on the engine.