Introduce Yourself

Thanks for your comments. I agree it was heavy for the available power. Perhaps 3 blades? The change to 38% COG was I think due to a misunderstanding of glide test - I could have had a poor trim to the elevator.

How does one recognise getting close to stall speed when sticking to a slower speed range for getting a feel for a new beastie?

Thanks. I look forward to figuring out how this site works and where stuff is.

jon
Without an airspeed indicator you have to rely on what a full light aircraft pilot uses, the feel & behaviour of the controls but in RC you have no 'control feel' so its down to understanding the way the plane behaves to any control input. This of course assumes you know what it is supposed to be doing. To make matters worse you have judge the behaviour from a distance and usually from below.
So the usual answer is to get '3 mistakes high' (that's pretty high!) and see for yourself what happens as you progressively slow down by slowly reducing the throttle but keeping the plane at a more or less the same altitude. The plane is likely to get harder and harder to keep a steady direction and the wings level.
At some point it will all go wrong and the plane is likely to roll over ending up diving towards the ground.
Let it dive for a bit to gain some speed so it is flying properly and once you understand its orientation then gently (also important) get it back to flying straight & level, hence the need to start with plenty of height.
The important bit is to make a mental note of how the plane is behaving and its attitude in the air before it all went wrong. This your stall warning experience. The bit after it all goes wrong is the stall recovery and is not too difficult if you have the height. If you don't you are most likely to crash hard. Many things can influence the how and when a plane stalls so it is worth repeating it quite often.

The rate at which things can go wrong in a plane is primarily down to its wing loading, its wing area divided by its weight. A lightly loaded model will do things slower and recover quicker, both important attributes during learning. There are guidelines for suitable wing loadings for different type of model plane.
A powerful & fast model of a military fighter plane will be going fast if things go wrong so 'unwanted contact with the ground' is much more likely before any recovery may even be possible.

More power, 3 blades?
Like for like a 3 blade prop will develop more thrust but each blade will operate a bit less efficiently so maybe 1/4 extra thrust but it still requires the full 1/3 extra 'electricity' to do it. Whether it can will depend on the capability of the motor, the speed controller and battery. If adding an extra blade means you actually need bigger and heavier bits much of the thrust advantage is lost being required just to keep the plane flying straight and level. Its all part of the joys of electric flying.
Now if you can reduce the planes structural weight its performance will improve without the need to change anything else.

Just to press home the point. My first 'modern' RC plane.

It flew well enough but with modest power and battery duration. It weighed 25 ounces.
Its latest form., 11 years later, and recently rebuilt after a crash 2 weeks ago. I still do that as well!

It now weighs just 13 ounces and uses the same 7x6 prop. As you can imagine its performance is nothing like the same!
That's quite enough for now.

Thanks for the description of stall. I suppose I fly low a lot of the time to stay out of the wind and to see the beastie better. Altitude flying in the park where I go means looking up at a rather painful angle. I did spend some of my last flight gaining altitude and then doing some throttle-off time. I should do more of that. It had more directional control gliding than I imagined.

The three mistakes is a great way of looking at things. I might have set myself up for some pain by sticking with wingspans of 900-1100mm as being easier to carry from my home to the park but also because the flight area is only 150m x 200m. One risk also is dogs deciding that the buzzing beastie is nice to chew on. -Jon

Thanks. I certainly recognise the one wing dropping - and that happening within 'one mistake' height. So fast and even reviewing a recording I had no idea what caused it - Klippy suggested it was a slow responding rudder combined with slow responding brain. Having mostly moved to ailerons I find the visual feedback is faster.

And also thanks about 'this is not the thread'. Haven't quite figured out the moving away from the Introduce yourself page. -Jon

Thanks. The 13 ounce is quite beautiful. I am currently working up a pusher design that should have much less weight in the tail and thus allow me to shift to a lighter battery. I hope to report back something interesting in the next couple of weeks. But probably I should use a different thread to do that.

Jon
Across the top of any page are a line of titles on a blue back ground - Home, Recent Topics, New Topic, My replies, Profile, Help & Search.

If you select Home you are taken to the initial site page which list all the post topics. It is several pages long
If you then scroll down a bit you will come across a Building Thread topic which would be a good place for you to describe your builds.
If you select that you are presented with a list of the posts member have already made of their own build projects.
On that page select the button in green marked New Topic and you are presented with a screen with a box to create a title for your Build Thread and an area to post text and pictures.
The clever bit is that once you have made the first post it will then appear under the Recent Posts button on the top of any page so provided you post fairly regularly, say every few weeks, you don't have to search the whole site to find it again, just select Recent Posts!
You Build Thread post will behave in exactly the same way as you have been adding to the your Introduce Yourself post which is under the heading Technical Stuff, Radio Gear, Electronics, not a logical place for it. It would be hard to find once you had forgotten where it was.
I hope this helps.