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Bobcat
10-28-2006, 04:59 PM
I have seen the post by Flyguy on G3 or 3.5. I would just like to know which version is the best for learning how to really fly an RC. I have never flown anything with a real motor just electic in real life.

So if you wanted to learn how to fly an RC what version would you choose?



Thanks,

--Bobcat

jbourke
10-28-2006, 05:26 PM
Either will work fine. I think G3.5 is slightly better than G3.

Jim

opjose
10-28-2006, 05:37 PM
3.5 fixes certain things that were observed in 3.0.

What most of the comments on 3.5 have been about, are the things that are a bit more subtle, but important to learning say 3D manouvers.

These items are a bit "off", and if fixed will result in an awesome flight model.

That said, don't avoid 3.5 because of the comments.

It's a worthwhile upgrade, but realize that at the moment the hovers, etc. may not reflect actual plane behaviour in the real world. It may be off, but it's not completely off.

jbourke
10-28-2006, 05:57 PM
opjose, I'm running a server right now. Stop in and demo the 3D flight model issues for me so I can understand. I'm having trouble seeing why G3.5 would be seen as less realistic than G3.

I agree it might be a bit harder to hover, but it seems more realistic to me.

You can set the prop wash factor to 120% or so if you want to make hovering easier.

Jim

opjose
10-28-2006, 06:38 PM
As per the other posts, the problems seem to center around tail authority and wing stall points.

For me, this manifested when I tried the snap rolls.

My real Ultimates don't have that "barrel roll" behaviour the G3.5 models have at say 60-70% throttle and at low rates.

My Ultimates all snap just fine at low rates (50-60% of full throws) and at medium flying speeds.

There is far less tendancy to push the nose up as much as in the G3.5 plane models, which causes the plane to revolve around an imaginary point about 1/3 of the way in the fuselage from the front.

Snap roll an Ultimate at full speed and high throttle.

Observe it's behaviour.

Now do the same thing at mid throttle and low rates.

Notice how with the latter it barrel rolls around a point outside the wing?

My real planes don't do this until they get REALLY slow...

I suspect that this is due to the wing not stalling out in 3.5 as it did before.

That is echoed by others....

e.g. check out the F117 in the swap pages.

Under 3.0 if you slowed this plane down too much, it would drop lock a rock after it winged over to one side.

Under 3.5 it just gracefully floats down.

On other planes the wings loose lift as the planes slow, but tip stalls don't seem to occur, or if they do they are very very gentle... I'd say too gentle.


There are complaints that hovering is harder than before.

That may well be.

I haven't quantified the latter.


Somewhere I had a video that I've been trying to find showing the Ultimates snap rolling with the planes filling the screen.

It showed the smaller Ultimates (such as my 40's and 120) snap rolling.

My edit for the Ultimate 40S in G3.0 mimiced the same behaviour as in the video and what I experienced at the field PERFECTLY, once I had the model flying correctly.


Under 3.5 I get the mid speed barrel roll effect which does not appear in the video or on the field.

Again at high speeds the "barrel roll" manifests as the high pitch up oblique to the direction of travel. It's TOO high (or the axis is too far back) in 3.5 I can't put my finger on this.

At low speeds the same pitch change and lack of one wing stall causes the plane to move out of the previous direction of travel and travel in the direction of the pitch up. The flight line FOLLOWS the direction the nose is pointed during the snap.

From a level mid throttle flight my Ultimates and Funtanas behave more like the G3.5 models at the higher speed. but with less tendancy to pitch up, or pitch into the direction commanded by the elevator...

That is the plane STALLS preventing this movement or nose up, and rolls instead.


I posted a recording that shows this with the Ultimate.

I did a high rate mid speed snap roll and you can see that the plane enters a barrel roll instead.

I then purposely duplicated this behaviour by slowly moving the controls immediately afterwards. The intent in the latter was to show that the plane behaves EXACTLY the same DURING the snap roll as it does when I am purposely moving the surfaces LIKE a slow speed barrel roll.

In the latter case the wings don't stall out.

In the snap rolls one wing don't seem to be stalling out as it should, or at the rate it should.

BTW: I never need to go full throttle at the field to perform snap rolls.